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1 FEDERAL COMMUNICATION AGENCY State Educational Institution of Higher Professional Education St. Petersburg State University of Telecommunications. prof. M.A. Bonch-Bruevich" "Arkhangelsk College of Telecommunications (branch) of St. Petersburg State University of Telecommunications. prof. M.A. Bonch-Bruyevich" Power supply of telecommunication systems Program, control task and guidelines for its implementation for students of correspondence courses in the following specialties: 70- Means of communication with moving objects; 709 - Multichannel telecommunication systems; 7 - Radio communication, broadcasting and television; 73 -Communication networks and switching systems. Arkhangelsk 03

2 Power supply of telecommunication systems. Working programm. Control task for students of the correspondence department. Compiled by: Popova O.M. ACT (branch) SPbSUT, Arkhangelsk. 03. Considered and recommended by the cycle commission of general professional disciplines of the Arkhangelsk College of Telecommunications (branch) of St. Petersburg State University of Telecommunications. prof. M.A. Bonch Bruevich. Arkhangelsk College of Telecommunications (branch) of St. Petersburg State University of Telecommunications. prof. M.A. Bonch Bruyevich, 03. Usl. oven l. 0.44

3 Explanatory note The subject "Power supply of telecommunication systems" is a compulsory discipline in the cycle of general professional disciplines for specialties: 709 Multichannel telecommunication systems, 7 Radio communication, broadcasting and television, 73 Communication networks and switching systems, 70 Communication means with mobile objects. The purpose of studying this discipline is the theoretical and practical training of students in the field of power supply of telecommunication systems to such an extent that they can ensure the competent operation of power supply devices, detect and eliminate faults in a timely manner, restore the operation of power supply equipment, evaluate the efficiency and energy intensity of power supply equipment. As a result of mastering the discipline, the student should know: sources of electrical energy for powering various devices used in communication organizations, power supply and power supply systems of communication organizations. must be able to: control the operating modes of the power supply installation, read block diagrams, apply knowledge in practice, monitor the performance of uninterruptible power supplies. In order to study the educational material, it is envisaged to perform one home test, independent work of students according to the educational and methodological map. The numbers of textbooks indicated in the educational and methodical map correspond to the numbers of textbooks in the list of references given at the end of the guidelines.

4 Educational-methodical map of the discipline "Power supply of telecommunication systems" Name of sections and topics Number of hours review laboratory hours are independent. work Section. General information about the power supply of communication devices Topic. Current state power supply devices. Types of energy sources Topic. Three-phase system 0. Section. Autonomous power sources Theme. Batteries Theme. Direct energy converters Section 3 Electromagnetic power supply devices Topic 3. Electrical reactors Educational literature index page Topic 3. Transformers Section 4. Alternating current rectification Topic 4. Rectifier circuits Topic 4. Rectifier operation for various types of loads Topic 4.3 Controlled rectifiers 0. Section. Voltage converters

5 Theme. Smoothing filters 0. Subject. Voltage converters Section 6. Voltage and current stabilizers Topic 6. Parametric voltage and current stabilizers Topic 6. Compensation DC voltage stabilizers Topic 6.3 Compensation regulators with pulse regulation Section 7. Rectifier devices Topic 7. Secondary power supplies Topic 7. Rectifier devices with transformerless input Section 8. Power supply system of a communications enterprise Topic 8. Power supply of communications enterprises Topic 8. Power factor correction Section 9. Power supply of equipment of communications enterprises

6 Topic 9. Power supply systems for communication equipment Topic 9. Uninterruptible power supply system direct current Topic 9.3 Uninterruptible AC Power System Section. Electrical installation of a communication enterprise Theme. Power supply of equipment (by specialty) Specialty 70 Power supply of equipment for communication with mobile objects Specialty 709 Power supply of NUP and NRP equipment Specialty 7 Power supply of equipment of radio communication and broadcasting systems Specialty 73 Power supply of automatic telephone exchange equipment Subject. The system of control and management of equipment of electrical installations Topic.3 Security of power supply. Grounding Topic.4 Calculation and selection of equipment for electrical installations of uninterruptible power supply Total for the discipline 8 36

7 WORKING PROGRAM OF THE EDUCATIONAL DISCIPLINE "POWER SUPPLY OF TELECOMMUNICATION SYSTEMS" Section General information about the power supply of communication devices Topic. The current state of power supply devices. Types of energy sources Introduction. Essence, role and place of discipline in the process of preparation for professional activity. The purpose and objectives of the development of energy, electronics and communication technology. Prospects for the development of power supply. Primary sources of energy, their application. Secondary energy sources, their application. Topic. Three-phase system Getting three-phase current. The connection of the phases of the generator and the consumer with a star. The connection of the phases of the generator and the consumer with a triangle. As a result of studying the section, the student should know: the main sources of power supply, the relationship between phase and linear values ​​of voltages and currents for various connection schemes. Section Autonomous power supplies Topic. Batteries Lead-acid batteries, classification, design. Work lead battery. Electrical parameters of a lead battery. Features of the operation of batteries. Modern types of batteries. Laboratory work "Studying the design of the battery" Topic. Direct energy converters Galvanic elements. Thermoelectric generators. Solar panels. Atomic batteries. As a result of studying the section, the student should have an idea: about the sources of direct current energy, about the scope of these sources; know: battery design, basic

8 electrical characteristics of batteries, features of their operation; be able to: decipher the symbol of batteries. Section 3 Electromagnetic power supply devices Topic 3. Electric reactors Magnetic circuit. magnetic materials. Chokes. Topic 3. Transformers The principle of the transformer, the classification of transformers. Transformer operating modes. The design of power single-phase transformers. Three-phase transformers. Laboratory work "Study of the operation of a single-phase transformer" As a result of studying section 3, the student should have an idea: about the classification of transformers, about the design and purpose of chokes and transformers; know: the principle of operation of a transformer, design features of a three-phase transformer, the relationship between phase and linear values ​​of voltages and currents for various winding connection schemes. Section 4 Rectification of alternating current Topic 4. Rectifier circuits Classification of rectifiers. Main parameters of rectifiers. Block diagram of the rectifier. Single-phase half-wave rectification circuit. Single phase bridge rectifier. Three-phase rectifier circuits, cascade rectifier circuits. Laboratory work 3 "Study of single-phase rectifier circuits" Practical work "Calculation of the rectifier" Topic 4. The operation of the rectifier for various types of loads The influence of the nature of the load on the mode of operation of the rectifier. Features of the operation of the rectifier on a capacitive load. Features of the operation of the rectifier on an inductive load. Voltage multiplication circuit. The operation of rectification circuits for the battery.

9 Topic 4.3 Controlled rectifiers Structural diagram of a controlled rectifier. Thyristor control methods. Single-phase thyristor rectification circuit. Three-phase bridge rectification circuit on thyristors. Laboratory work 4 "Investigation of the thyristor rectification circuit" As a result of studying section 4, the student should know: the operation of single-phase and three-phase current rectification circuits; features of the operation of controlled rectifiers; have an idea: about the features of the operation of the rectifier for resistive and reactive loads; about the elements used in rectification circuits. Section Voltage converters Topic. Smoothing filters Rectified voltage ripple, its influence on the operation of communication equipment. Requirements for smoothing filters. Smoothing filter parameters. Inductive, capacitive filters. Smoothing RC filters. L-shaped LC filter. Multi-section LC smoothing filter. resonance filters. Active smoothing filters. Laboratory work "Investigation of the properties of smoothing filters" Topic. Voltage converters Classification of voltage converters. Structural diagram of the voltage converter. Transistor voltage converters. Thyristor voltage converters. Laboratory work 6 "Investigation of DC voltage converters" As a result of studying the section, the student should have an idea: about voltage ripple, its effect on the operation of equipment, about secondary power sources, about the use of inverters and converters; know: the device, the conditions for the effective operation of smoothing filters; operation of DC converters.

10 Section 6 Voltage and current stabilizers Topic 6. Parametric voltage and current stabilizers Classification of stabilizers. Basic parameters of stabilizers. Parametric stabilizers of direct voltage, current. Topic 6. Compensation DC voltage stabilizers Structural diagrams of compensation stabilizers with continuous regulation. Serial type voltage stabilizer. Compensation stabilizers in integrated design. Topic 6.3 Compensation stabilizers with impulse control Classification of impulse regulators. Structural diagram of a pulse stabilizer Schemes of the power part of a pulse stabilizer. Two-position switching DC voltage stabilizer. Voltage stabilizer with pulse-width current regulation. Laboratory work 7 "Investigation of a compensation DC voltage stabilizer" As a result of studying section 6, the student should have an idea: about destabilizing factors, about the elements used in stabilizers; know: the features of the stabilizers, the main characteristics of the stabilizers. Section 7 Rectifiers Topic 7. Secondary power supplies General information about rectifiers. Structural diagram of VUT series rectifiers. Structural diagrams of secondary power sources with output voltage stabilization. Laboratory work 8 "Study of the VUT rectifier device" Topic 7. Rectifier devices with a transformerless input Purpose and technical characteristics of VBV-60. Structural diagrams of VBV. circuit diagram VBV rectifier. The work of the power part of the circuit. Stabilization and regulation of the output voltage.

11 Laboratory work 9 "Studying the rectifier device VBV" As a result of studying section 7, the student should have an idea: about the nomenclature of VUT, VBV, about the features of the operation of rectifiers with a transformerless input; know: block diagram of the power part of rectifiers, design, methods of voltage stabilization, the basics of technical operation. Section 8 Power supply system of a communications enterprise Topic 8. Power supply of communications enterprises Electrical installations of communications enterprises. Appointment. Composition. Classification of electrical receivers according to the conditions of reliability of power supply. Structural diagrams of power supply to consumers of the first and second categories. Own power plants. Transformer substations. Laboratory work "Study in switching - distribution equipment of alternating current" Topic 8. Correction of power factor Power factor. Capacitor plant. Passive power factor correctors. Power factor correction in WBV. As a result of studying section 8, the student should have an idea: about the classification of electrical installations of consumers according to the conditions of power supply, about the appointment of power factor correction, ways to increase it; know: the appointment of the main elements of electrical installations; be able to: draw up an electrical installation diagram for a specific situation. Section 9 Power supply of equipment of communication enterprises Topic 9. Power supply systems of communication equipment Classification of power supply systems. Buffer power supply system. Ways to improve the nutritional quality of the buffer system. Batteryless power supply system.

12 Topic 9. Uninterruptible DC power supply system The purpose of the installation and the principle of operation of the SBP. Structural diagram of DC UBP. DC power supply devices (UEPS) Laboratory work "Research of the device uninterrupted power supply direct current (UEPS)» Topic 9.3 AC uninterruptible power supply system Classification of uninterruptible power supplies. Uninterruptible power supply with double conversion. Converter rectifier. Converter inverter. Disadvantages of the UPS and how to eliminate them. Laboratory work "Study of thyristor inverter IT-0/" Laboratory work 3 "Study of AC UPS" As a result of studying section 9, the student should have an idea: about modern power supply installations; know: power supply systems of communication equipment, operating modes of power supply installations, composition and purpose of power supply installations and uninterruptible power supply installations. Section Electrical installation of a communications enterprise Theme. Power supply of equipment (by specialty) Specialty 70. Power supply of equipment of means of communication with mobile objects Features of power supply of equipment of means of communication with mobile objects. Power supply installation of base stations and switching center. Power supply for mobile phones. Specialty 709. Power supply of NUP and NRP equipment Electrical installation of a serviced amplifying station. Organization of remote catering. Schemes and parameters of remote power circuits. Features of the construction of the electrical installation of the power supply of the NRP FOCL. Structural diagram of the electrical installation at the NRP FOCL.

13 Specialty 7. Power supply of equipment of radio communication and broadcasting systems Electrical installation of radio relay station. Electrical installation of the television center. Power supply of equipment of radio transmitting centers. Specialty 73. Power supply of ATS equipment Power supply of ATS equipment. Features of power supply of electronic automatic telephone exchanges. Structural diagram of the power supply of electronic automatic telephone exchange. Topic. System of control and management of equipment of electrical installations Power supply systems of communication enterprises. The main provisions of the system. The structure of the control and management system. information sharing infrastructure. Topic.3. Power supply security. Grounding General safety requirements. Functions of security systems that depend on the power supply. Electrical safety. Fire safety. Information Security. Types of grounding systems. Electrical connection of earthed parts of equipment. Protection of equipment from impulse currents and surges. Devices of protective shutdown of a source. Laboratory work 4 "Familiarization with the existing electrical installation of a communications enterprise (by specialty)" Topic.4 Calculation and selection of equipment for electrical installations of uninterruptible power supply Initial calculation data. Calculation and selection of battery type. Calculation and selection of rectifiers. Calculation of DC power distribution network. As a result of studying section 9, the student should have an idea: about the electrical installations of base stations and the switching center (specialty 70), about the electrical installations of radio communications and broadcasting enterprises (specialty 7), about electrical installations of electronic exchanges (specialty 73), about the features of organizing remote power supply on FOCL ( specialty 709), General requirements and electrical safety measures; know: about the features of the power supply of equipment for communication with moving objects

14 (specialty 70), schemes for organizing remote power supply (specialty 709), features of power supply of electronic exchanges (specialty 73), features of power supply of radio communication enterprises (specialty 7), purpose and types of grounding systems; be able to: choose the type and number of rectifiers, batteries. General instructions for the implementation and execution of control work The control task is selected in accordance with the individual cipher of the students. Before completing the task, you should study the relevant sections of the textbook. 3 Familiarize yourself with the guidelines for the implementation of this control task. 4 Control work should be done neatly in a separate notebook in a cage, observing the margins. It is permissible to perform control work using a computer in A4 format. The following rules must be observed when completing the work: write down the complete condition of the problem and the initial data for the calculation; calculations in tasks should be accompanied by the necessary brief explanations; the formulas used for the calculation should be presented in a general form, and the symbols included in the formula should be explained; the result of the calculation must be calculated with an accuracy of three significant digits, not counting the zeros in front of them; graphic representation and symbol of circuit elements must be made in accordance with the requirement of GOST; drawings should be numbered in the order in which they appear and accompanied by captions; at the end of the work, you should indicate the list of used literature, publisher, year of publication, the student's personal signature and the date of completion of the work; the work is sent for review in accordance with the study schedule.

15 Control task TASK Draw a diagram of the rectifier specified for your option in the table and use timing diagrams to explain the principle of its operation. Calculate a given rectifier according to the following points: Select the type of silicon diodes. Determine the effective values ​​of voltage and current in the secondary winding of the transformer. 3 Determine the transformation ratio of the power transformer. 4 Determine the coefficient of performance (COP) of the rectifier. Determine the pulsation factor Km. 6 Determine the ripple frequency f of the fundamental (first) harmonic. The data for the calculation are given in the table. Table Initial data Initial data Rectified voltage U 0, V Rectified current I 0, A 3 Rectification circuit Option number of transformer windings 4 Mains voltage U c, V Mains frequency f c, Hz Ripple coefficient of the first harmonic at the load (at the filter output) K OUT 0.00 0.00 0.003 0.009 0.004 0.00 0.00 0.003 0.00 0.00

16 Guidelines for solving the problem Before you start solving the problem, you should study the pages of the textbook recommended in the text of the program. To select the type of silicon diodes, it is necessary to determine the reverse voltage across the diode U OBR and the average forward current through the diode I СР. The data for their calculation are given in the table. The type of silicon diode is selected according to the table. 3, based on the calculations of the values ​​of U OBR and I SR, so that the allowable values ​​of the corresponding values ​​for the selected type exceed the calculated ones, U OBR max >U OBR; I PR SR > I SR. The calculation of the effective values ​​of voltage U and current I in the secondary winding of the transformer is determined by the formulas in the table. 3 The transformation ratio of a power transformer is calculated by the formula: U ktr, () U where U is the effective value of the phase voltage in the primary winding of the transformer, is taken equal to the mains voltage U C, V; U is the effective value of the voltage in the secondary winding of the transformer, V (see p.). 4 Calculation of rectifier efficiency. The efficiency of the rectifier without taking into account the smoothing filter is determined by the formula: Р0, () Р Р Р 0 TR D where Р 0= U 0 I 0 active power at the load, W; - power losses in the transformer, W; R TR R D - power losses in diodes, W. 4. The calculation of power losses in the transformer is determined by the formula 3: P P, (3) TP where P TP is the calculated power of the transformer, is determined according to the table for a given rectifier circuit, W; - transformer efficiency, for calculations it is taken equal to 0.8. TR TR

17 Table Parameters Reverse voltage on the diode Uobr Average value of the forward current through the diode Iav 3 Rectifier phase m 4 Effective value of the voltage of the secondary winding of the transformer U Effective value of the current of the secondary winding of the transformer I 6 Effective value of the current of the primary winding of the transformer I 7 Estimated power of the transformer Ptr single-phase bridge single-phase full-wave with transformer mid-point output Uo 0.43 Uo Io 0.707 Io 0.8 Io 0.8 Io, Po,34 Po,34 Po Po

18 Table 3 Type of diodes U arr max Ipr.av. Upr.av. Iv.av. Diode type U arr max Ipr.av. D43A D43B D4 D4A D4B D46 D46A D46B D47 D47B D48B KD0A KD0G D30 D303 D304 D30 D0A D0B D0V D0G KD0A KD0V KD0D KD0Zh KD0K, 3, 0.9 0.9 0, 0.3 0, 0.3 0.8 0, 8 0.8.0, KD0M KD0R KD03A KD03B KD03V KD03G KD03D KD06A KD06B KD06V KD08A KDA KDB KDV KDG KD3A KD3B KD3V KD3G D6A D6B D0A D0B D0V D0G D0D D0E D0J D0I D-D-6 D-4 V V0 DL- DL-6 DL- DL-3 DL-40 VL VL VL,,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3, 3 0.7 0.7 0.7 0, 0, 0, 0, 0, 0.0 0.0 4.0 6.0 6.0.0.0.0.0 4.0 4.0 4 .0.0 8.9

19 4. The calculation of power losses in diodes depends on the rectification circuit: for a three-phase single-half-wave rectification circuit and a single-phase current rectification circuit with the output of the middle point of the transformer, the power losses in diodes are calculated by the formula 4, W: Рd = Upr.av Io, (4) where Upp.cp - allowable forward voltage on the selected diode, V (see table 3). in bridge rectification circuits, the current flows through two diodes connected in series, therefore, the power losses in the diodes are determined by the formula, W: Рd = Upr.av Io. () The ripple coefficient of the main (first) harmonic at the output of the rectifier is calculated by formula 6: K P m. (6) 6 The pulsation frequency of the fundamental (first) harmonic f,Hz is determined by the formula 7: f = m fc, (7) where m is the number of rectified current pulses per period (see Table); fc - network frequency, Hz. TASK Calculate the smoothing Г - shaped LC - filter, included after the rectifier, according to the following points: Determine the smoothing coefficient q. Determine the parameters of the elements of the smoothing filter. 3 Draw a diagram of the calculated L - shaped LC - filter, taking into account the number of links in the filter. The data for the calculation are given in Table. (8)

20 where Kp is the ripple factor of the first harmonic at the filter input (at the rectifier output), is determined for a given rectifier circuit according to formula 6; Kp.out - pulsation coefficient of the first harmonic at the filter output (at the load), see table. If q<, то применяется однозвенный LC - фильтр, и в этом случае qзв= q, где qзв - коэффициент сглаживания одного звена LC - фильтра. Если q >, then a two-section LC filter is applied. Since the use of parts of the same type is more economical than different types, the same elements L and C are included in both links of the two-link filter. In this case, the smoothing coefficient of each link is determined by formula 9: qsv q. (nine). Calculate the values ​​of the inductance and capacitance of the smoothing filter. One of the conditions for choosing the inductance of the filter inductor is to ensure the inductive response of the filter to the rectifier. The minimum value of the inductance of the inductor that satisfies this condition is determined by the formula, Hn: L U0 (m) m I 3.34 f DRmin rated capacity, based on the calculated value of capacitance C and the rated voltage of the capacitor U HOM, the value of which is determined by the formula: 0 C () () U nom >, U 0. () If in table 4 there is no capacitor with the calculated capacity for the required voltage , then you should choose a capacitor with the maximum rated capacitance for the calculated rated voltage and connect from two to five such capacitors in parallel to each other. In this case, it may turn out that the total capacitance of five parallel-connected capacitors C GEN B is several times (...) less than the calculated value of the filter capacitance C. Obtaining the calculated value of the filter capacitance by further increasing the number of capacitors is impractical, therefore, the total capacitance C COM of the selected capacitors is considered nominal filter capacity.

21 In this follows the value of the inductance L DR min should be increased by the same factor as C OVR is less than the calculated filter capacitance C, since it is necessary to comply with the condition LC = const..3 Draw a smoothing filter circuit, taking into account the number of links and the number of capacitors connected in parallel in each link of the filter, which were obtained as a result of your calculation. Table 4 - Capacitors with an oxide dielectric Type Rated voltage, V K 0-6, K 0-8 6, K K 0-3A K K, Rated capacitance, microfarads; ; 47; 0; 0; 470; 00; 00; 000 ; ; ; 47; 0; 0; 470; 00; 000 ; 47; ; ; 47; 0; 0; 470; 00; 00; 000 ;,; 4.7; ; 47; 0; 00 ;,; 4.7; ; 0 ;,; 4.7; ; ; 47; 0; ; ; ; ; ; ; 000; 000; ; 000; ; 4700; ; ; 00; ; 47; 0; 0; 470; ; 47; 0; 0; 470 4.7; ; ; 47; 0; 0,; 4.7; ; ; 47; 0; 0000; 000; ; ; 000; ; 00; 00; 3300; ; 40; 0; 330; 470; 680; 00; 000; 0047; 68; 0; 0; 0; 330; 470; 680; 0047; 68; 0; 0; 0; 330; ; 0; 0; 470; 00; 00; 4700; ; 0; 0; 470; 00; 00; 4700; 000 ; 47; 0; 0; 470; 00; 00; 47; 0; 0; 470; 00; 00; 47; 0; 0; 470; 00; 00 4.7; ; ; 47; 0; 0; ; 4.7; ; ; 47; 0

22 TASK 3 Calculate the EPU-60 (EPU-48) power supply unit according to the following points: Select the type and number of batteries in the battery required for emergency power supply to the load. Decipher the designation of the selected batteries. Select the type of power supply installation of the communication enterprise (UEPS) and the number of rectifiers of the VBV type. 3 Calculate the energy parameters of the rectifier-battery installation. The data for the calculation are given in the table. Table Initial data Load current I n, A Rated voltage U nom, V Power supply category First consumer Electrolyte temperature, to 4 0 Option number Special group First Special group Ik First Special group Ik First Special group Ik First Special group Ik Guidelines for solving the problem 3 Calculation and selection of the battery. Battery Capacity Calculation The battery provides power to the load in emergency mode. The required capacity of a lead-acid battery OP Z S (with liquid electrolyte), reduced to normal discharge conditions, is determined by formula 3, Ah: Iloadtp Qt, (3) [ 0.008(t 0)]

23 where Q t is the estimated battery capacity in ampere-hours, reduced to normal electrolyte temperature (0 0 C), Ah; I LOAD load current specified in the initial data, A; t p battery discharge time in hours, depends on the category of power supply: for consumers of a special group of the first category - hours, for consumers of the first category - 8 hours, h; - capacity selection coefficient, depending on the discharge time, t p; at t p =h q =0.94 at t p =8h q =0.64 t o - the actual electrolyte temperature indicated in the initial data. Selection of the battery type. Since the battery consists of two parallel groups, the resulting capacity value must be divided by two. The choice of battery type is made according to table 6. For example, the calculated battery capacity Q t \u003d 800A h is divided by two and we select a battery of type 6 OP Z S 40 with a nominal capacity Q nom \u003d 40A h. A battery is selected whose nominal capacity should exceed the calculated one. In the selected battery type, the first number of the code corresponds to the number of positive plates, letter designation stands for “stationary maintenance-free batteries with tubular positive plates”, the last number shows the nominal capacity Q NOM of the battery at - hourly discharge with rated current..3 The number of cells in one battery group is determined by formula 4: U NOM n= (4) where U nom \u003d 60 (48) - rated voltage at the load, V; rated voltage of one battery, V.

24 Table 6 Element type 3 OP ZS 0 Capacity, Ah Discharge current, A hours hours 3 0, 3 0, OP ZS 00 OP ZS 0 6 OP ZS 300 OP ZS 30 6 OP ZS 40 7 OP ZS OP ZS OP ZS 800 OP ZS 00 OP ZS 00 OP ZS 00 OP ZS 87 6 OP ZS OP ZS 00 4 OP ZS Calculation and selection of the power supply installation of a communications enterprise (UEPS). Calculation of the load current UEPS. The rectifier unit must provide power to the load and charge the battery after it is discharged during shutdown

25 electricity. Therefore, the total current of the EPU (I EPU) should be the sum of the load current (I LOAD) and the battery charge current (I CHAR.). The charge current of two battery groups is calculated by the formula, A I ZAR = 0. Q nom () where Q nom is the rated capacity of the selected battery, Ah . From table 7, you should select a device of the UEPS-3 or UEPS-3K type for Unom = 60V or 48V and the value of I EPU with VBV rectifiers (rectifier devices with a transformerless input). For example, at the estimated current I EPU = 0A, U NOM = 60V, select UEPS-3 60 / M. In the selected type of UEPS-3: the number 60 means the rated voltage, V; digit 0 - maximum output current when fully equipped with rectifiers, A; digits 06 - the maximum number of rectifiers installed in the device; figures 06 - the number of rectifiers installed in the device; index M - modernized. Table 7 Device type UEPS-3 60/M Rectifiers VBV Type Quantity, pcs. VBV 60/ -3K 6 UEPS-3 60/300--M UEPS-3K 60/80-44 UEPS-3 48/ M UEPS-3 48/360--M UEPS-3K 48/0-44 VBV 60/ - 3K VBV 60/0-3K VBV 48/30-3K VBV 48/30-3K VBV48/-3K

26 where kw is the number of rectifier modules connected in parallel; I VBV is the maximum current of one rectifier, A One backup of the same type should be added to the selected working set of VBV. Types and main electrical characteristics of rectifiers are given in Table 8. Table 8 Maximum Adjustment range of output output voltage, power, current, A V W Efficiency,9 0.9 0.99 40.9 0.9 Power factor 0.99 0.98 Note: symbol of the rectifier type given in the table 4, is decoded as follows: VBB - rectifier devices with a transformerless input; the figure in the numerator is the rated output voltage, V; the figure in the denominator is the maximum load current, A; number 3 (or) execution number; the letter K - the presence of a power factor corrector. 3 Calculation of the energy parameters of the rectifier-battery installation. 3. The maximum power consumption of UEPS-3 from the AC mains, taking into account the efficiency of the rectifier, is calculated by the formula 8, kW: where VBV EPU NOM R max = VBV - efficiency of the rectifier. I U (8)

27 3. The total power consumed by the installation from the AC network is calculated by the formula 9, kV A: P MAX P S = cos, (9) where cosφ is the power factor of the selected type of WWV. TASK 4 Draw an electrical functional diagram of the EPU-60 (48) according to the data obtained in task 3. Indicate the composition and purpose of the main equipment of the EPU. 3 Consider the power supply circuits of the load according to the EPU scheme. Explain how the uninterruptible power supply of communication equipment is provided from the EPU: 3. in the presence of an alternating current network (normal mode), (for options from to 4); 3. when the AC mains fails (emergency mode), (for options from to 7); 3.3 when restoring the AC network (post-accident mode), purpose (for options from 8 to); Guidelines for the implementation of task 4 A typical scheme of EPU-60 is shown in the figure. The diagram should show the number of rectifier modules (RBV) that resulted from your calculation. A typical EPU-48 scheme is constructed in a similar way. The figure shows structural scheme EPU-60, called the buffer modular power supply system. A feature of such systems is the parallel connection of the battery to the output of the rectifiers and the supplied load. EPU-60 (48) includes: a set of VBV rectifiers, consisting of K modules for powering communication equipment, charging and recharging the battery; automatic switches A-A-K for connecting rectifiers to the AC inlet shield SHPTA; automatic switches A-A-K for connecting the output of rectifiers to the battery and load; two-group storage battery AB iab; automatic (contactor) deep discharge AGR for disconnecting the battery from the equipment in case of deep discharge; battery circuit breakers AB, AB for connecting the battery to the load;

28 current shunts for measuring current in the battery circuit Sh and in the load circuit Sh; automatic switches An-An-m for connecting the load; controller for monitoring the condition of rectifiers, circuit breakers, fuses; to control the voltage and current of the battery and load; its shutdown during deep discharge; ambient temperature; for the capacity of the battery, the presence of all three phases of the mains. When any of the machines is turned off or the protection is triggered, the corresponding information appears on the controller display. Figure - Electrical functional diagram EPU-60 EPU operation In normal mode, the power supply of communication equipment and continuous recharging of the battery is carried out from the working EPU. Circuit breakers A-A-K and A-A-K are closed. In emergency mode, the equipment is powered by a discharging battery. In order to prevent sulfation of batteries as a result of their unacceptable deep discharge,

29, an AGR contactor is introduced into the power supply system, disconnecting the battery from the equipment. When the power supply is restored, rectifiers provide power to the equipment and charge the battery without disconnecting it from the load. Advantages of the buffer modular power supply system: high quality of the generated energy, as the smoothing stabilizing properties of the storage battery connected in parallel to the load are used; the minimum number of devices included in the EPU, which ensures low cost and high reliability; high efficiency, almost equal to the efficiency of VBV; high power factor (in case of using rectifiers with power factor corrector). List of used sources: Power supply of devices and telecommunication systems; Textbook for universities /V.M. Bushuev, V.A. Deminsky, L.F. Zakharov and others - Moscow: Hotline Telecom, 009. Shchedrin, N.N. Power Supply of Telecommunication Systems: Textbook for SPO. Textbook for open source software. Moscow: UMC of the Federal Communications Agency, 0. Additional sources: Sizykh, G. N. Power supply of communication devices [Text]: textbook for technical schools / G. N. Sizykh. - Moscow: Radio and communications, p. Khilenko, V. I. Power supply of communication devices [Text]: textbook / V. I. Khilenko, A. V. Khilenko. - Moscow: Radio and communications, p. 3 Materials of the website of the Ferropribor plant. 4 Materials of the NPP GAMMAMET website.

FEDERAL COMMUNICATION AGENCY state-financed organization higher professional education St. Petersburg State University of Telecommunications named after prof.

FEDERAL EDUCATIONAL AGENCY STATE EDUCATIONAL INSTITUTION OF HIGHER PROFESSIONAL EDUCATION "TYUMEN STATE OIL AND GAS UNIVERSITY" INSTITUTE OF CYBERNETICS, INFORMATION SCIENCE

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MINISTRY OF EDUCATION AND SCIENCE of the Russian Federation R.E.

information and communication technologies and services are currently a key factor in the development of all areas of the socio-economic sphere. As elsewhere in the world, in Russia these technologies are showing rapid growth. Thus, in the last five years, the growth of the communication services market in our country has been about 40% annually.

For the first time, a special investment fund appeared in the structure of federal budget expenditures for 2006. Directions of expenses of this fund are the subject of heated discussions in society and government structures. In particular, telecommunications projects could also be financed from the investment fund, primarily in order to create a digital infrastructure on a nationwide scale.

The reliability and availability of communications and telecommunications services in our country has long been an acute problem, and such information services as high-speed Internet access, video communications, cable TV, IP telephony, etc., are developing mainly in Moscow and St. Petersburg, although the need for such services is felt by all residents of Russia.

And while we are debating whether to allocate funds from the investment fund to such infrastructure projects as the construction of interregional digital highways (which, by the way, could serve as a catalyst for the development of other segments of the IT industry and the economy as a whole), around the world the time is approaching for a radical increase in the capacity of digital information networks, which will inevitably lead to the emergence of qualitatively new types of services that, perhaps, will simply be inaccessible to us.

So, in September 2005 in San Diego (USA) the regular iGrid conference and exhibition (http://www.igrid2005.org/index.html) was held. This is an international movement that develops the idea of ​​lambdaGrid: the word lambda means wavelength, and Grid means "grid" with a hint of a geographical network of parallels and meridians. In general, this movement is not so new, and its technological principles have long been developed. We are talking about DWDM technology (Dense Wavelengh-Division Multiplexing), that is, global multiplexing of digital communications. Perhaps the closest and fairly accurate analogy for understanding the foundations of this technology is the transition from the telegraph and spark radio by Marconi and Popov to modern multi-frequency broadcasting, that is, the networked world is moving from primitive data transmission technologies over fiber optics to simultaneous use when transmitting waves of different wavelengths. Simply put, signal receivers / transmitters (DWDG-enabled FO tranceiver) turn from black and white to multi-colored. At the same time, the opto-

the conductor already has a fairly wide transparency band, or rather, a wide light beam retention band inside the optical fiber with low losses for emission out of the direction along the fiber axis, as a result of which it is not necessary to lay new cables.

In addition, the new DWDM transceivers are quasi-duplex, that is, one fiber can transmit data in both directions at the same time. In numerical terms, this means that DWDM technologies will make it possible to transmit up to 160 streams simultaneously over the current ten-gigabit fiber optic channels, and we are talking about trunk, long channels, including transcontinental ones. It turns out that all of the so-called progressive humanity is suddenly given such an unexpected gift as an increase in network bandwidth by two orders of magnitude. In addition, the presence of many free channels will allow them to be allocated as needed and to send data streams in parallel instead of sequentially transmitting them over one channel, as was the case before. Naturally, this requires new hardware and software solutions and the integration of today's network owners into a single information infrastructure.

Unfortunately, such technologies will not reach Russia very soon, because so far, according to the map of world digital communications, our country is not filled with fiber optic lines.

Russian features

Serious changes are expected in Russia, primarily in the field of PSTN (Public Switched Telephone Network) telephone communications. common use, PSTN). It is assumed that already this year subscribers will have the opportunity to choose an operator for long-distance and international communications. In addition to Rostelecom, Interregional TransitTelecom (MTT), Golden Telecom, TransTelecom and others plan to provide their services, although only Rostelecom is operating without any particular complaints today. In principle, it should be possible to use the services of several companies at once, that is, the user will choose whose minutes on the desired direction are cheaper. Each operator will be assigned a code starting with the number "5" (51, 52, etc.), which will need to be dialed after entering the intercity. In the meantime, after dialing the usual intercity "eight", the subscriber will get to the usual "Rostelecom". And for those who are already cheaper to call using alternative operators today, you need to write a statement to your telecom operator, and then the G8 will bring them to the appropriate network.

The share of time-based payments for fixed-line telephone conversations continues to grow, gradually catching up with mobile communications in terms of cost. According to the new version of the communication law that came into force on January 1, 2004, operating companies are obliged to provide the subscriber with two types of tariffs - time-based and fixed (of course, if there is a technical possibility). At present, not all interregional companies (RTOs) of Svyazinvest are even regional centers equipped with systems for time-based accounting of the cost of negotiations - most do not have enough money for technical re-equipment and the introduction of billing systems. And yet, in many regions of RTOs this year, subscribers were given the opportunity to pay for telephone calls in a new way.

And in accordance with the Decree of the Government of the Russian Federation approved on October 24, 2005 "On state regulation of tariffs for public telecommunications and public postal services", telecom operators, if technically possible, must already establish three mandatory tariff plans:

• with a time-based payment system;
• with a subscriber payment system;
• with a combined payment system, according to which the meter is turned on after "pronouncing" a certain amount of time.

In addition, the operator will have the right, in addition to these basic tariffs, to introduce any number of other tariff plans, and the consumer can choose the one that he likes and can afford.

At one time, during the controversy over the "time-based" a lot of copies were broken, and as a result, the Duma rejected the first version of the law on communications, which assumed the forced transfer of all fixed-line subscribers to the time-based payment for negotiations, and the current law was adopted, giving the citizen the right choose the type of tariff. Of course, not all regions have this very “technical ability” to establish a time-based payment system (for this, many need to radically change equipment, and, as always, there are not enough funds for this), but in some regions, many subscribers already use the “time-based” , if only for the reason that at one time they were transferred to it forcibly - in particular, these are almost all Uralsvyazinform subscribers. In other regions where such technical capabilities are available, but there was no forced transfer, about half of the subscribers switched to the “time-based” service on their own.

Finally, Moscow City Telephone Network OJSC (MGTS) is also developing three tariff plans for local telephone communications for its individual subscribers. MGTS submitted an application for approval of tariff plans in December 2005, and the approval itself may take place in early 2006. Technical capability MGTS has long had time-based recording of the duration of local telephone connections: both time-based accounting systems at telephone nodes and a billing system have been introduced.

MGTS is the main telephone operator in Moscow, and the subscription fee for individuals is 200 rubles, which is currently slightly higher than the national average. So, today the average monthly fee for a fixed-line subscriber in Russia is 160 rubles, while the break-even point for the provision of such a service, according to the Ministry of Information and Communications, is 210 rubles. And if you plan to further expand communication services, then, according to officials, the average monthly fee should be raised to 230-250 rubles, and such an increase will undoubtedly follow in the next two or three years. However, if today we sharply raise the average subscription fee by 50 percent, then fixed-line subscribers will massively abandon such lines in favor of mobile telephony. Indeed, otherwise, fixed-line communication will practically equal in cost to mobile, but with incomparably greater convenience of the latter. For example, in Moscow, time-based payment of outgoing calls is expected up to 1.8 rubles, which is approximately 0.06 dollars, that is, the same amount that a not the cheapest mobile operator has to pay for 1 minute outgoing call over his network. And since the growth of subscription fees in all regions of the country is inevitable, mobile communications are becoming more and more attractive.

With the entry into force of the rules approved by the Government of the Russian Federation for the provision of telephone services from January 1, 2006, re-registration of a home telephone from one owner to another will not exceed the amount of one monthly subscription fee for telephone services (now the fee for re-registration of a telephone is charged in the amount of a fee for its installation and amounts to several thousand rubles). In addition, competitions will now be held in the regions for the right to provide universal telephone services using payphones, as well as for the right to provide communication services for data transmission and access to the Internet.

In the meantime, the State Duma decided to equalize the responsibilities of mobile and fixed telephony and adopted in the first reading the draft law “On Amending Article 54 of the Federal Law “On Communications””, which is supposed to legislate the principle of free of charge all incoming calls to any phones for the called person. In accordance with this bill, any telephone connection established as a result of a call by another subscriber is not subject to payment by subscribers, except for those established with the help of a telephone operator with payment at the expense of the called person.

If such a law is adopted, it will be another blow to the fixed-line system.

IP telephony

IP telephony (or VoIP, Voice over Internet Protocol - voice over Internet Protocol technology) is another technological innovation that came to us along with the Internet and indicates that the world will no longer be the same as before. VoIP is essentially a technology that allows you to reduce the cost of long-distance and international calls by 3-5 times. This happens due to the fact that most of the way the voice signal travels over the Internet in digital form, and this costs much less money and allows you to achieve a higher quality of communication than using conventional analog lines.

Over the past year, sales of IP telephony communication systems have surpassed that of standard telephone line solutions. From June 2004 to June 2005, sales of VoIP systems increased by 31%, while standard solutions sold 20% worse (according to Networking Pipeline, citing Merrill Lynch, an analytic company). This bi-directional process appears to be the reason why the overall telephone systems market grew by only 2% year-on-year to $2.24 billion.

Internet providers and telephone operators are actively developing the IP telephony market in all developed countries. For example, in the USA today such packages of services are offered, when for about $ 25 you can get a monthly subscription that allows you to call any subscribers in the USA and Canada for a whole month without any restrictions. These innovations are also actively encouraged by the American authorities, who, as you know, have set themselves the goal of promoting the development of Internet technologies in their country and, in connection with this, have almost completely exempted the Internet industry from taxes in the coming years. Obviously, with the advent of cheap VoIP services available to the mass consumer, according to all the laws of a market economy, any normal person will use them, and not the more expensive services of standard long-distance and international operators. Russian economists estimate the turnover of the IP-telephony services market that has formed in our country to date at $300 million a year. Various firms are now operating in this market - both VoIP departments of large telecommunications companies and small local operators.

But if in developed countries such a situation is considered natural, then in other countries it causes serious concerns - and first of all among monopoly operators of traditional communications, who see a direct threat to their profits in the development of IP telephony. And, contrary to the laws of the free market, some monopoly companies are trying to prevent this development, using all the means available to them. For example, in Costa Rica, where for many years the market has been dominated by a single national telephone provider, they are currently trying to legislate the activities of VoIP firms by imposing additional taxes on them as intermediary companies that generate added value. Moreover, it is proposed even to completely ban the work of VoIP providers, equating their activities with criminal ones. Many Costa Rican experts assess this prospect as catastrophic for the country's economy, since recently the industry of remote programming (outsourcing) has been actively developing in Costa Rica, for which the ability to make cheap international calls is a significant help.

Our companies, traditional monopoly operators such as Rostelecom or MGTS, do not lag behind the Costa Ricans, and they also try to declare the business of VoIP firms illegitimate with the help of administrative resources. The use of an administrative resource for commercial purposes, according to representatives of independent VoIP companies, can be seen, say, in a decree of the Government of the Russian Federation, which on March 28, 2005 put into effect a system developed under the supervision of the Ministry information technologies and communication instructions entitled "Rules for the connection of telecommunication networks and their interaction." In the opinion of the specialists of these companies, these rules actually prohibit the provision of IP-telephony services, setting obviously impossible obligations and strict restrictions for them. As a result of such pressure on local VoIP providers, calling by IP telephony to Russian regions or CIS countries costs 2-3 times more than to America and even to Australia.

However, the liberalization of the long-distance communication market cannot be stopped in any case, since this is one of the key requirements in the negotiations on Russia's accession to the WTO (World Trade Organization).

Internet via modem

Thus, in 2005, the tariffs of Svyazinvest companies increased by 20-25%, during

2004 - by 30%, and the rate of increase in fixed-line tariffs in 2006 is again projected at the level of 30%. In particular, tariffs will increase when alternative tariffs for RTOs are approved. However, we should not expect a nightmarish emptying of our wallets from the new procedure for providing telephony services - on the contrary, those who do not talk on the phone for very long can even save on time-based fixed-line communication.

Another thing is access to the Internet via a PSTN modem (dial-up), where there is no longer any need to wait for indulgences from time. And, apparently, this way of accessing the Internet will gradually become a thing of the past. Of course, PSTN-Internet providers, even in conditions of non-alternative time-based work, find ways to ensure that their subscribers do not pay for the Internet even by the minute, that is, according to the bills of the telephony operator. For example, in those cities where time-based payment is already used, providers introduce a callback: you call the modem pool, the connection is interrupted, and you receive a callback from the pool already as an incoming one. Windows XP, by the way, perfectly fulfills such a callback, and therefore the connection is at the expense of the Internet provider. The ways of existence of PSTN providers are also various contracts with telecom operators that provide for special (possibly short) telephone numbers, by calling which you connect without a monthly fee. However, in the same way, you can agree with the telephone operator on the installation of ADSL equipment (DSLAM) at communication centers, and as a result, switch to more advanced Internet access technologies that do not occupy telephone lines at all.

In addition, the manufacturing quality of the PSTN modems themselves is getting worse and worse, because the production of modems for dial-up communication lines has long been no longer the leading branch of the IT industry. In the civilized world, this type of communication becomes irrelevant due to the spread of high-speed information highways and because of their availability for the mass consumer - here both ISDN and ADSL, and fiber optic communication lines, and Wi-Fi, and even cellular data transmission systems such as GPRS, etc. Accordingly, manufacturers are losing interest in the release of new products, and some have already curtailed the production of analog modems. And since the sales of this equipment for the advanced and most profitable areas of the market have fallen sharply, manufacturers are trying to make the hardware part of their products as cheap as possible, which, of course, has a negative effect on the quality of communication using such modems.

In addition, due to the general improvement in the quality of telephone communications in those countries where analog modems are still sold, manufacturers cease to care that their equipment works on noisy lines of outdated exchanges. Thus, modern analog modems can only be used as a backup communication channel: where they still work confidently, as a rule, alternative methods of accessing the Internet are already well developed, and where such technologies are not developed, even modern analog modems work badly. And there seems to be no way out of this vicious circle.

The Russian market for broadband access is growing primarily due to the individual segment: the number of home connections in the first half of 2005 increased by more than 1.5 times and reached 870,000 subscribers. Thus, 85% of new broadband connections are for individual users and only 15% for the corporate market segment.

The clear growth leader among broadband technologies is DSL, with DSL connections growing by over 60%, and if only home connections are taken into account, the DSL market in this segment has grown by over 80%. But even despite such an impressive dynamics of DSL operators, Ethernet from home networks remains the most popular way for home users to connect - in total, they still have 2-3 times more subscribers than DSL operators.

However, Russia looks good only in terms of growth dynamics: the number of broadband connections in our country, according to international news agencies, increased by 52%, while the growth in the whole world was only 20%, and in Eastern and Central Europe (without accounting for Russia) - approximately 30%. Thus, in terms of dynamics, Russia is ahead of all major markets broadband access, second only to the Philippines, Greece, Turkey, India, Czech Republic, South Africa, Thailand and quite a bit Poland.

However, in terms of total broadband connections, Russia's position is very weak - it accounted for only 0.7% of all broadband connections in the world in mid-2005, according to Point-Topic. Only about 1.5 million broadband connections in Russia today look shabby compared to 53 million in China, 38 million in the US or even 3.5 million in the Netherlands. Nevertheless, Russia entered the Top 20 of the Point-Topic rating in terms of the number of broadband connections on the first attempt and, according to preliminary data, increased this number by 85% by the end of the year. As a result, our country is now in 17th-18th place, ahead of not only Poland, but also the more developed Sweden. By the way, the coverage of PSTN subscribers with broadband services (that is, the potential opportunity to connect to ADSL) only in the central region (excluding Moscow), according to Svyazinvest, amounted to 3,746,825 people, while the actual number of ADSL access subscribers is not exceeds 224 thousand subscribers in this region.

Even worse is the situation with the penetration of the "broad band" into the regions - today there are only 0.9 connections for every 100 inhabitants. According to this indicator, Russia is 10-30 times behind South Korea, Japan, the United States, as well as the leading countries of Western Europe, and 4 times behind the average of the new members of the European Union. Even in China, the penetration rate of broadband Internet access among Chinese families is about 3% (for the whole country, it is 3 times higher than ours). True, in the capital and the Moscow Region, the prevalence of broadband access is quite high (4.4 broadband connections per 100 inhabitants) and is quite comparable with the level of Hungary, Poland or Chile, but the indicators for the rest of Russia are extremely low - only 0.4 connections per 100 inhabitants, approximately like Jamaica or Thailand.

Instead of a conclusion

let's look again at the map of global digital communications: let's not flatter ourselves that there are places worse than Russia, but let's hope for high growth dynamics and wait for our government to have the sense to direct part of the investment fund's costs to finance telecommunications projects, and first the turn is those that will allow to level the digital infrastructure on a nationwide scale and save it from distortions towards the capital.

In the meantime, even at the Russian post office points of collective access to the Internet are installed in no more than a few thousand post offices. Federal State Unitary Enterprise Russian Post planned, of course, to increase the number of such points to 10 thousand by the end of 2005, but what is tens of thousands of points on the scale of such a huge country as ours?

Practically all systems of train radio communications, station communications with mobile objects, repair and operational, service and operational radio communications, etc., are implemented in the 2, 160, | 530 and 450 MHz bands on radio stations with angle modulation with fixed assignment of communication channels. Only in some subsystems of the "Transport" system it was envisaged to use the principle of equally accessible channels (trunking).

The improvement of technological railway radio communication networks is carried out in two stages, taking into account the stages of development of the railway communication network and the creation of a single integrated digital communication network.

First step.

Implementation of train radio communications in the hectometer range (2 MHz) based on modernized radio equipment: RS-46M, RS-23M, SR-234M, US-2/4M, dual-band radio stations RV-1M, RV-1.1M.

Implementation of train dispatching duplex radio communication of the "Transport" system in the 330 MHz band on the main directions of the railway network of Siberia and Far East, which will allow organizing radio communication networks when using three-band radio stations RV-1M on locomotives.

Train dispatching radio communication is created in two ranges - decimeter (330 MHz) and hectometer (2 MHz).

In the 330 MHz band, the main dispatch communication channel is organized, providing continuous radio communication between the DNC, ECC and the locomotive train dispatcher (TNC) with train locomotive drivers within the entire dispatch area.

The network of duplex train dispatching radio communication provides a test check of the serviceability of stationary and portable equipment with the display of control results. In the hectometer range, a backup dispatch communication channel is organized, which is used mainly for radiotelephone conversations between dispatchers and drivers.

Communication of train locomotive drivers with chipboard and crossings is organized in the hectometer (2 MHz) and meter (160 MHz) ranges.

Communication of train locomotive drivers with those on duty at the locomotive depot, militarized security guards, repair managers with various categories of subscribers equipped with portable radio stations is organized in the meter wave band (160 MHz) with the possibility of receiving fixed commands and messages from specialized outdoor devices or portable radio stations at the portable radio station. radio stations (“Attention, moving”, “Repair of the track”, “Fire on the train”, “Emergency on the train”, etc.).

The connection of train locomotive drivers with drivers of oncoming and following trains is organized in the hectometer and meter wave ranges and with assistant drivers when the latter leave the locomotive cab - in the meter wave range. At the same time, assistant drivers must have portable radio stations.

The connection of the chief (foreman) of a passenger train with the driver of a train locomotive, with those on duty at stations and crossings and with various categories of workers equipped with portable radio stations (on duty at the platform, at the station, police officers, etc.) is organized in the meter wave band (160 MHz).

The intra-train communication and public address network ensures the transmission of information to the passengers of the train and the communication of the head of the train with the members of the brigade.

3. Development and implementation of the train dispatch radio communication PRS460 on the main directions of the road network of the European part of Russia and the Ural regions. At the same time, dual-band duplex-simplex radio stations of the decimeter (460 MHz) and meter (160 MHz) bands will be installed on mobile railway transport facilities. During the transitional period, radio stations of the hectometer range 42RTM-A2-ChM (ZHR-K-LP) or RK-1 will remain in operation.

Station and repair-operational radio communication (RORS) using fixed channels in the meter wave range (160 MHz). The development trend of RORS is associated with the introduction of networks using equal channels (trunking networks).

Radio communication using equal channels in the range of decimeter (460 MHz) waves.

Trunking networks should include subscribers of management staff, as well as subscribers of the following networks of station and repair and operational communications: track repair services, power supply, communications and signaling services; paramilitary security workers; the head of the passenger train with those on duty at the stations, linear police stations; capital construction services; platforms for loading and unloading operations; cargo and commercial work; radio networks of the locomotive economy; points of commercial inspection of wagons; forwarding companies for the delivery of containers and cargo; radio networks of fire and recovery trains.

Second phase.

Creation of digital cellular mobile radio networks adopted by the UIC (GSM-R) in accordance with the UIC-751.4 Recommendations, which will allow organizing channels that ensure the transmission of critical commands in the train traffic control system; train dispatching radio communication to ensure communication between the dispatching apparatus and the drivers of train locomotives; train technological radio communications for solving all technological problems, including station and repair-operational radio communications (except for shunting and hump communications), as well as passenger service radio communications due to the excess capacity of train technological radio communications and with access to the ZhATS network.

Organization of passenger service communication and intra-train radio communications using railway technological radio communications, general land mobile radio communications and mobile satellite communications.

Intra-train radio communications should be built in accordance with the UIC Recommendations (TLS-568, taking into account the requirements for train radio communications ShS-751.3) and provide:

Loud-speaking notification of passengers within the entire train by the head of the train and the train dispatcher using the train dispatcher radio communication; within the carriage - by the conductor of the train;

Communication of the head of the train with the conductors and drivers of the locomotive within the train, and at stops - and within the platforms;

Communication of train passengers with JATS subscribers, subscribers in other trains, access to the public telephone network; communication with subscribers included in the railway technological train radio communication system operating in the mode of digital trunking radio networks and/or in the GSM-R system.

The need to improve technological radio communications is due to the following tasks facing the railway transport:

Improving the management structure and technology of transport;

Increasing employee productivity and reducing operating costs;

Improving traffic safety based on the development of train traffic control systems over the radio channel;

Improving the quality of passenger service, developing the service sector and commercial passenger transportation.

Requirements for the operational services of railway transport to the technological radio communication system:

Increasing the number of subscribers of railway radio communication networks and equipping employees of all services of the Ministry of Railways with radio equipment;

Expansion of communication zones and increasing the reliability of communication of the dispatching apparatus when organizing train and shunting radio communications;

Organization of radio communication networks for employees of repair and maintenance departments;

Providing a number of categories of railway subscribers with mobile (wearable) radio terminals with the possibility of establishing operational communication in telephone mode or data transfer mode with the MPS apparatus, departments and road departments via the MPS general technological communication network.

At the present stage of development of mobile railway radio communications, the technologies for its use can be significantly changed. Until now, radio communication has been used mainly in the radiotelephone mode and only in certain technological processes, for example, to control shunting locomotives or locomotives of connected trains - in the mode of transmitting telemetric information.

At present, considerable attention should be paid to solving the problems of automating the control of train traffic via a radio channel, monitoring the technological processes of transport and information support automated control systems.

An analysis of the capabilities of modern mobile radio communications shows that their use allows solving many applied problems, in particular:

Automatic control of shunting and hump locomotives at stations;

Control and transmission of diagnostic information about the state of the train and locomotive to the depot, maintenance centers;

Notification of train drivers and on-board controls using equipment for monitoring the technical condition of the rolling stock on the move of the train (DISK, PONAB, etc.);

Interval regulation of train traffic, including for high-speed lines,

Semi-automatic blocking on low-traffic lines;

Fire and burglar alarms in depots, places of sludge of rolling stock;

Organization of radiotelephone communication, transmission of facsimile, video information from the place of restoration work with the possibility of negotiating and transmitting information to the level of the Ministry of Railways of Russia, departments and departments of railways;

Notification of repair teams and train drivers about approaching the place of repair work;

Transmission of telemetric information to control stationary power supply facilities, traction substations, barriers at unguarded crossings, compressor stations, etc.;

Management of connected trains of increased mass and length;

Identification and control of the location of trains at road junctions, the boundaries of dispatching sections and stations with the transmission of data about the train, including information from the natural sheet in real time to the dispatch control center of the road to the DISPARK system, etc.

Monitoring the location of trains carrying especially valuable and dangerous goods;

Access services to the Express-3 system for ordering and purchasing tickets on trains.

Based on a detailed study and analysis of the needs of all railway transport services in the transmission of voice information and data, and in order to improve the management of the transportation process based on meeting these needs, the “Operational and technical requirements for the digital radio communication system of Russian railway transport” have been developed.

Digital radio systems

In connection with the modernization of technological radio communication systems, the Ministry of Railways of Russia is transitioning to digital systems. The TETRA trunking communication system and the GSM-R cellular communication system are at the testing stage.

general characteristics TETRA standard, The TETRA standard describes a digital radio communication system that provides a wide range of telecommunication services. These include individual and group calls, access to the public telephone network, data transfer, and various additional services.

The most important property of the TETRA standard is that it allows organizing the simultaneous operation of many independent virtual networks belonging to different departments and organizations within the same system. The subscribers of each of them, communicating with each other, will not feel the presence of "foreign" networks in any way. At the same time, if necessary (for example, in emergency situations), their interaction can be quickly organized.

The TETRA standard provides reliable information security. For this, a system of measures is provided, including the mandatory encryption of radio communications. Unauthorized access to the TETRA standard system is impossible - at each connection, the subscriber and the network conduct mutual authentication using a cryptographic algorithm. Users with high privacy requirements can use the end-to-end transmission of encrypted information - this method eliminates the interception of messages not only on the air, but also in the network infrastructure.

TETRA standard systems provide subscribers with a wide range of data transmission services - from sending short text messages to organizing channels that allow information to be exchanged at a speed of 28.8 kbps. A TETRA network subscriber can simultaneously use voice and data communication services. In addition, TETRA subscriber radio stations with a built-in graphic display and support for WAP (Wireless Application Protocol) can access departmental information resources. corporate networks and the Internet.

The TETRA standard allows you to assign a certain priority level to each subscriber. Users with high priority have unconditional access to the network - even if all channels are busy, the system, when requested, will immediately terminate one of the current connections and provide a communication channel. The TETRA standard uses special speech signal processing methods that provide not only the correct transmission of the timbre of the voice, but also the preservation of intelligibility when working in conditions of strong external noise (for example, at construction sites, railway stations, etc.). When a subscriber moves from one service area to another, the conversation is not interrupted.

Thus, the TETRA standard allows you to create digital radio networks that fully meet the needs of a wide variety of subscribers. Despite the fact that today the standard includes all the specifications necessary for manufacturers, work on its expansion continues. So, a technology is being developed that will significantly increase the range of radio communication - up to 100 km. In addition, the TETRA PDO specification, a special version of the standard focused only on packet data transmission, is being improved.

In accordance with the V+D specification implemented in the TETRA standard, one of three services is provided to the user for data transmission: circuit switched data (CD), packet switched data (PD) and short message transmission (SDS). The CD method is mainly designed to transport large amounts of data over the main traffic of the channel, with each 25 kHz channel using one of the four timeslots. It is in this case that the TETRA standard provides the desired quality of service, since the necessary bandwidth can be reserved on demand. If the user needs to increase the throughput, two to four time slots can be combined and the communication channel can be end-to-end, and the user will have to lower the security level of such a channel to increase the speed.

As for the PD mode, today it is the most interesting and promising method, which is connected mainly with global trends, in particular, with the Internet. The total spread of the IP protocol and, as a result, applications based on IP, has also found its way into TETRA networks. In this case, the mobile radio acts as the IP client and the TETRA network as the transport medium. Such a scheme is characterized by increased flexibility and reliability due to the existence of various ways of delivering the radio signal, readiness for increased traffic, the ability to connect almost any computer equipment to the radio station and, of course, support for standard products and applications.

Functional diagrams for building various communication networks of the TETRA standard are presented as a set of network elements connected by certain interfaces. TETRA networks contain the following main elements:

Base transceiver station BTS (Base Transceiver Station) - a base stationary radio station that provides communication in a certain area (cell). Such a station performs the main functions associated with the transmission of radio signals: interfacing with mobile stations, encryption of communication lines, spatial diversity reception, control of the output power of mobile radio stations, control of radio channels;

BCF (Base Station Control Function) - a network element with switching capabilities that manages several base stations and provides access to external networks, and is also used to connect dispatcher consoles and terminals for operational and maintenance;

The base station controller BSC (Base Station Controller) is a network element with greater switching capabilities compared to the BCF device, allowing data to be exchanged between several BCFs. BSC has a flexible modular structure that allows the use of a large number of different types of interfaces;

Dispatching console - a device connected to the base station controller via a wired line and providing information exchange between the operator (network manager) and other network users. Often used for broadcasting information, creating user groups, etc.;

Mobile station MS (Mobile Station) - a radio station used by mobile subscribers;

Fixed radio station FRS (Fixed Radio Station) - a radio station used by a subscriber in a certain place;

Maintenance and operation terminal - a terminal connected to the control device of the BCF base station and designed to monitor the state of the system, diagnose faults, record billing information, make changes to the subscriber database, etc. With the help of such terminals, the local network management function LNM (Local Network Management) is implemented. Due to the modular principle of equipment design, TETRA communication networks can be implemented with different hierarchical levels and different geographical extent (from local to national). Database management and switching functions are distributed throughout the network, ensuring fast call transfers and maintaining limited network availability even when communication with individual elements of the network is lost.

At a national or regional level, the network structure can be implemented on the basis of relatively small but complete TETRA subnetworks interconnected via an ISI interconnect to create a common network. In this case, centralized network management is possible. A variant of constructing such a network is shown in Fig. 21.7.

Each TETRA subnet performs its own control and switching functions, and provides the opportunity for higher-level centralized control. The structure of the subnetwork depends on the load as well as on the requirements for link establishment efficiency. If channel redundancy is not required, it is possible and sufficient to create a subnet according to the star configuration. When using linear paths, the TETRA subnetwork can be implemented as a long line (chain). In this case, each BCF control unit, along with the required communication range, provides local access to external networks. The simplest TETRA subnet configuration includes only one BCF module.

In TETRA communication networks, various methods of providing fault tolerance are provided, allowing, in the event of a failure, individual elements networks to maintain full or partial performance, possibly with a deterioration in a number of parameters,

such as connection establishment time, etc. For national level networks, as a rule, several alternative routes for connecting regional level networks are used. In regional networks, such alternative routes are used to connect base station controllers. In addition, for regional networks mutual copying of databases in base station controllers is provided.

General characteristics of GSM-R. The GSM-R radio communication system was developed on the basis of the GSM cellular standard and is focused on meeting the needs of European railways in exchanging information with mobile objects, as well as creating conditions for the implementation of traffic control systems using radio channels through the use of 4 MHz bands in the 876- 880 MHz and 921-925 MHz (Fig. 21.8).

The railway section is divided into several districts covered by RBC control centres. Control commands are formed in the system, speed control is carried out, and the location of the train is determined. During the communication between the train and the RBC center, duplex transmission is possible. For example, the center transmits permission for the movement of the train, and the train - information about its location.

The GSM standard was adopted by the International Union of Railways (UIC) in 1993 as the underlying technology for the implementation of a railway digital communication system. But since this standard did not have the service required for professional systems, in 1993 the UIC made a request to ETSI (European Telecommunication Standards Institute) to implement additional features of ASCI. These include extended multilevel priorities, redundancy, broadcast voice announcement and voice group call services. Along with ASCI to meet the requirements of the railways for the services of train, shunting radio communication, data transmission for train control, telecontrol, etc. Functional addressing, location-based addressing, and high priority call handling must be implemented.

The GSM-R network can be divided into several subsystems:

Onboard devices;

Stationary devices;

Control center.

The division of tasks between the three control subsystems is carried out as follows:

The control center takes over the management of routes and provides trains with a conflict-free assignment of track sections (regulation of the order of trains);

On-board devices issue tasks to stationary devices in accordance with the routes assigned to them and control the movement of trains;

Stationary devices, in turn, perform the functions of control and monitoring of switches, approaches to passenger platforms and crossings.

Each of the subsystems has its own access to the radio communication network and is able to interact with other subsystems. The distribution of security functions between several subsystems required the formation of a single database. This is necessary primarily to coordinate the data on the trains and in the control center. Therefore, the subsystems work with the data of a single line atlas containing all the information describing this line. It includes, along with topological information (line model, location of switches and crossings), data on the maximum allowable speeds and addressing in the radio communication system.

The GSM-R network consists of cells located along the railway or in the territory of the station. Each cell of cells is equipped with one or more transceivers depending on the load. Each base station controller is assigned to specific cell numbers. The base station controllers are connected to the MSC (Mobile Switching Center)/VLR (Visitor Location Register) control center. The MSC establishes external connections and provides an interface to other networks (Figure 21.9), where the following abbreviations are used:

AUC (Authentication Center) - authentication center;

BSC (Base Station Controller) - base station controller;

BTS (Base Station System) - base station transceiver;

GCR (Group Call Register) - call grouping register;

EIR (Equipment Identification Register) - equipment identification register;

SMS (Short Message Service) - short message service;

VMS (Visitor Management Server) - movement management server;

OSS (Operation System Server) - control center server;

OMC (Operation and Maintenance Center) - control and maintenance center;

SCP (Service Control Point) - communication services control point;

IN (Intelligent Networks) - intelligent network;

PABX (Private Automatic Branch Exchange) - automatic leased circuit switcher.

All network components in the GSM-R standard interact in accordance with the signaling system ITU-T SS.No (CCITT SS No. 7).

The switching center serves a group of cells and provides all types of mobile station connections.

LITERATURE

1. Arkhipov E. V., Gurevich V. N. Handbook of electrician of STsB. M.: Transport, 1999. -351 p.

2. Bukanov M.A. Train traffic safety (in conditions of violation normal operation signaling and communication devices). M.: Transport, - 112 p.

3. Volkov V.M., Zorko A.P., Prokofiev V.A. Technological telephone communication in railway transport. M.: Transport, 1990. -293 p.

4. Volkov V.M., Lebedinsky A.K., Pavlovsky A.A., Yurkin Yu.V. / Ed. V.M. Volkov. Automatic telephone communication in railway transport. M.: Transport, 1996. - 342 p.

5. Gapeev V.I., Pishchik F.P., Egorenko V.I. Ensuring traffic safety and injury prevention in railway transport. Minsk, 1994. - 310s.

6. Grachev G.N., Kolyuzhny K.O., Lipovetsky Yu.A., Tsyvin M.E. Code auto-blocking on an electronic element base / Automation, remote control and communication, No. 7, 1995. - S. 28-29.

7. A. A. Kazakov, V. D. Bubnov, and E. A. Kazakov, Automated systems for interval regulation of train traffic. M.: Transport, 1995.- 320 p.

8. Kozlov P.A. The course - on the integrated automation of marshalling yards // Automation, communication, informatics, No. 1, 2001. - P. 6-9.

9. Kondratieva L.A., Borisov B.B. Automation, telemechanics and communication devices in railway transport. M.: Transport, -407 p.

10. Kosova VV Operational-technological connection of the railway department. M.: Transport, 1993. - 144 p.

11. Kravtsov Yu.A., Nesterov V.L., Lekuta G.F. Systems of railway automation and remote control. M.: Transport, 1996. - 400 p.

12. Ivanova T.N. Subscriber terminals and computer telephony. M.: Eco-Trends, 1999. - 240 p.

13. Instructions for the movement of trains and shunting work on the railways of the Russian Federation: TsD-790 / Ministry of Railways of Russia. M.: Tekhinform, 2000. - 317 p.

14. Instructions for ensuring the safety of train traffic during the performance of maintenance and repair of signaling devices: TsShch / 530 / Ministry of Railways of Russia. M.: Transizdat, 1998. - 96 p.

15. Instructions for signaling on the railways of the Russian Federation / Ministry of Railways of Russia. M.: Transport, 2000. - 128 p.

16. Instructions for the operation of railway crossings of the Ministry of Railways of Russia: TsP / 483 / Ministry of Railways of Russia. M.: Transport, 1997. - 103 p.

17. Petrov A. F. The device of the barrier of the railway crossing // Automation, communication, informatics, No. 7, 1998. - S. 24-28.

18. Rules for the technical operation of the railways of the Russian Federation / MPS of Russia. M.: Tekhinform, 2000. - 190 p.

19. Sapozhnikov V.V., Elkin B.N., Kokurin I.M., Kondratenko L.F., Kononov V.A. Station systems of automation and telemechanics. M.: Transport, 1997. - 432 p.

20. Blind N.N. Synchronous digital networks SDH. M.: Eco-Trends, 1998, - 148 p.

21. Sokolov S. V. Automated workplace of a train dispatcher - AWP DSC "Setun" / Automation, communication, informatics, No. 5, 2001, -S. 13-16.

22. Modern telecommunications of railway transport / Ed. G.V. Gorelov. - UMK MPS RF, 2000. - 577 p.

23. Ubaidullaev P.P. Fiber-optic networks. M.: Eco-Trends, - 240 p.

24. Chernin M.A., Protopopov O.V. Automated dispatch control system // Automation, communication, informatics, No. 10, - 48 p.

25. S. A. Shchigolev, V. I. Talalaev, V. A. Shevtsov, and B. S. Sergeev, “Algorithm for the functioning of the UKP CO system and linkage with semi-automatic blocking,” Avtomatika, svyaz, informatika, No. 5,1999. - S. 10-14.

INTRODUCTION 3

TRAIN CONTROL SYSTEMS

Chapter 1. Elements of traffic control systems 6

System classification 6

General information about the elements of systems 9

General information about the relay 11

DC relay 16

AC relay 24

Transmitters and electronic devices 26

Chapter 2. Traffic lights 31

Purpose, types and installation locations of traffic lights 31

Traffic signaling 37

Classification and arrangement of traffic lights 43

Chapter 3. Power supply of automation and telemechanics devices.. 46

Power supply equipment 46

Power systems 49

Chapter 4. Rail circuits 52

Device, principle of operation and purpose of track circuits.. 52

Track circuit classification 56

Basic operating modes of track circuits 58

Reliability of track circuits 61

Track circuit diagrams 63

Chapter 5. Semi-automatic blocking 73

Purpose and principles of construction

semi-automatic lock 73

Methods for fixing the follow-up

and train arrival control 78

Relay semi-automatic blocking system GTSS 80

Chapter 6 Automatic Lock 91

General information and classification of auto-lock systems 91

Alarm systems 94

DC auto-lock principles 97

Principles of building a double-track

AC auto-lock 107

Chapter 7

alarm and hitchhiking 119

General information 119

Automatic locomotive

alarm continuous type 121

Automatic locomotive signaling

a single row with a continuous communication channel 129

Automatic brake control system 130

Chapter 8. Fencing devices at crossings 133

Purpose and types of automatic

fencing devices at the crossing 133

Crossing traffic lights control

and automatic barriers 139

Railroad crossing barrier 143

Chapter 9. Electrical interlocking of arrows and signals 147

Purpose and classification of systems

electrical centralization 147

Station equipment devices

relay centralization 151

Switch drives 170

Arrow Control Schemes 175

Relay centralization of intermediate stations 179

Relay interlocking for medium and large stations 189

Principles of building a block

route-relay centralization 201

Microprocessor systems EC 211

Chapter 10. Mechanization and Automation

humps operation 223

Principles of mechanization and automation

marshalling yards 223

Hump ​​car retarders 227

Hill control panel 229

Integrated automation

marshalling yards 237

Actions of the duty officer on the slide in case of violation of normal operation

automation and mechanization devices 241

Chapter 11. Dispatch centralization 244

General information 244

Command and control devices 246

The main requirements for

to the train dispatcher and station attendant 254

Chapter 12

for the movement of trains and systems of technical diagnostics 256

General information 256

Frequency dispatching system 258

Automated system

supervisory control ASDC 261

Telecontrol system 262

Condition Monitoring Systems

rolling stock on the move train 264

Chapter 13

in case of malfunction of signaling devices 271

Ensuring the safe movement of trains

with semi-automatic lock 271

Organization of safe train traffic at AB 274

Organization of safe traffic at crossings 277

Organization of safe traffic

trains in case of malfunction of EC devices 281

Section II COMMUNICATION

Chapter 14. Features and purpose of railway communication 291

State of the communication network of the Ministry of Railways of Russia 291

Basic concepts and definitions 292

Types of railway communication and their purpose 293

Prospects for the development of telecommunications

in railway transport 295

Chapter 15 Communication Lines 297

Purpose and classification of communication lines 297

Air and cable communication lines 298

Fiber optic communication lines 302

Chapter 16 Telephones and Switches 306

The principle of telephone transmission of speech.

Two-Way Telephone Transfer Scheme 306

The design of telephones.

Telephone sets for technological communication 309

Telephone switches.

Purpose and principle of operation 313

Operational switches

and operational and technological communications 315

Digital telephones and switches 319

Chapter 17. Telegraph communication and data transmission 324

The principle of organization and purpose of telegraph communication 324

Telegraph devices.

Automatic telegraph communication 328

Creation of a data transmission network for Russian railways 334

Chapter 18

in railway transport 339

Principles of automatic switching.

General information about PBX systems 339

Coordinate system exchanges and quasi-electronic exchanges 344

Digital PBX 347

Operational-technological equipment

time-switched connections 349

Chapter 19. Multichannel transmission systems 352

Features of communication channels and methods of their compaction 352

Analog multichannel transmission systems 358

Digital multichannel transmission systems 360

Digital Primary Network 360

Chapter 20

in railway transport 367

Classification and purpose

technological communication 367

Selective calling systems 375

Main and road technological communication 382

Operational and technological connection

railway departments 385

Station technological connection 391

A single digital platform for organizing general technological and operational-technological communications 395

Chapter 21. Radio communication 399

Basic concepts 399

Station radio 402

Train radio 404

21.4. Repair and operational radio communication 406

Radio relay 408

Prospects for the development of railway radio communications 411

Digital radio systems 416

REFERENCES 425

In given units.

MEANS OF COMMUNICATION:

DEVELOPMENT,

PROBLEMS,

PERSPECTIVES

MATERIALS

SCIENTIFIC AND PRACTICAL CONFERENCE

MUNICIPAL EDUCATIONAL INSTITUTION

"NOVOSELITSKAYA SECONDARY EDUCATIONAL SCHOOL"

NOVGOROD DISTRICT OF NOVGOROD REGION

The conference materials contain information from the simplest sound and visual means for transmitting signals and commands to the most modern ones. The historical path of development and improvement of means of communication, the role of scientists and practitioners, the latest achievements in physics and technology, their practical use are shown.

Lesson - the conference contributes to the growth of the teacher's creative potential, the formation of students' skills of independent work with various sources information, allows you to comprehend previously acquired knowledge in a new light, systematize and generalize them. Participation in the conference develops the ability to speak publicly, listen and analyze the messages of their classmates.

The materials of the conference are designed for creative use and are intended for teachers to help in preparing and conducting lessons in physics.

FROM THE HISTORY OF COMMUNICATIONS

Communication has always played an important role in the life of society. In ancient times, communication was carried out by messengers who transmitted messages orally, then in writing. Signal lights and smoke were among the first to be used. During the day, against the background of clouds, smoke is clearly visible, even if the fire itself is not visible, and at night - a flame, especially if it is lit on an elevated place. At first, only predetermined signals were transmitted in this way, say, "the enemy is approaching." Then, by arranging several smokes or fires in a special way, they learned to send whole messages.

Sound signals were used mainly over short distances to gather troops and the population. To transmit sound signals, the following were used: a beater (a metal or wooden board), a bell, a drum, a trumpet, a whistle and covers.

The veche bell in Veliky Novgorod played a particularly important role. At his call, Novgorodians gathered at a veche to resolve military and civil matters.

For command and control of the troops were of no small importance different shapes banners, on which large pieces of various fabrics of bright color were fastened. The military leaders wore distinctive clothes, special headdresses and signs.

In the Middle Ages, flag signaling appeared, which was used in the fleet. The shape, color and design of the flags had a specific meaning. One flag could mean a sentence ("The ship is diving" or "I require a pilot"), and it, in combination with others, was a letter in a word.

From the 16th century in Russia, the delivery of information with the help of the Yamskaya chase became widespread. Yamsky tracts were laid to important centers of the state and border towns. In 1516, a yamskaya hut was created in Moscow to manage the post office, and in 1550 a yamskaya order was established - the central institution in Russia that was in charge of the yamskaya chase.

In Holland, where there were many windmills, simple messages were transmitted by stopping the wings of the mills in certain positions. This method has been developed in the optical telegraph. Towers were erected between cities, which were located at a distance of line of sight from each other. Each tower had a pair of huge jointed wings with semaphores. The telegraph operator received the message and immediately passed it on, moving the wings with levers.

The first optical telegraph was built in 1794 in France, between Paris and Lille. The longest line - 1200 km - operated in the middle of the 19th century. between Petersburg and Warsaw. The line had 149 towers. She was served by 1308 people. The signal along the line traveled from end to end in 15 minutes.

In 1832, an officer of the Russian army, physicist and orientalist Pavel Lvovich Schilling invented the world's first electric telegraph. In 1837 S. Morse developed and supplemented Schilling's idea. By 1850, the Russian scientist Boris Semenovich Jacobi created a prototype of the world's first telegraph apparatus with direct printing of received messages.

In 1876 (USA) he invented the telephone, and in 1895 a Russian scientist invented the radio. Since the beginning of the twentieth century. radio communications, radiotelegraph and radiotelephone communications began to be introduced.

Map of the Yamsky tracts of the 16th century. Russian postal routes of the 18th century.

COMMUNICATION CLASSIFICATION

Communication can be done by signals of various physical nature:

Sound;

Visual (light);

Electrical.

According from the nature of the signals used to exchange information means of transmission (reception) and delivery messages and documents communication can be:

Electrical (electrocommunications);

Signal;

Courier postal.

Depending on the linear means used and the signal propagation medium, communication is divided by gender on the:

Wired connection;

Radio communication;

Radio relay communication;

Tropospheric radio communication;

Ionospheric radio communication;

Meteor radio communication;

space communications;

optical communication;

Mobile communications.

According to the nature of the messages transmitted and mind communication is divided into;

telephone;

Telegraph;

Telecode (data transmission);

Facsimile (phototelegraph);

television;

video telephone;

Signal;

Courier post.

Communication can be done through transmission of information over communication lines:

plain text;

coded;

Encrypted (using codes, ciphers) or classified.

Distinguish duplex communication, when simultaneous transmission of messages in both directions is ensured and interruption (request) of the correspondent is possible, and simplex communication when the transmission is carried out alternately in both directions.

Communication happens bilateral, in which duplex or simplex information is exchanged, or unilateral, if there is a transmission of messages or signals in one direction without a return response or confirmation of the received message.

SIGNAL COMMUNICATION

Signaling communication carried out by transmitting messages in the form of predetermined signals using signaling means. In the Navy, signal communications are used to transmit service information between ships, vessels and raid posts both in plain text and in codes typed.

For signal communication by means of subject signaling, one-, two- and three-flag codes of signals of the Navy, as well as a flag semaphore, are usually used. For the transmission of plain text and signal combinations of arches by light-signal devices, signs of the telegraphic Morse code are used.

Ships and ships of the Navy and raid posts for negotiations with foreign ships, merchant ships and foreign coastal posts, especially on issues of ensuring the safety of navigation and the protection of human life at sea, use the International Code of Signals.

Signal means, means of signal visual and sound communication, used to transmit short commands, reports, warnings, designations and mutual identification.

Visual means of communication are divided into: a) means of subject signaling (signal flags, figures, flag semaphore); b) means of light communication and signaling (signal lights, searchlights, signal lights); c) pyrotechnic means of signaling (signal cartridges, lighting and signal cartridges, marine signal torches).

Sound signaling means - sirens, megaphones, whistles, horns, ship's bells and foghorns.

Signal means have been used since the time of the rowing fleet to control ships. They were primitive (drum, lit fire, triangular and rectangular shields). Peter I, the creator of the Russian regular fleet, set up various flags and introduced special signals. 22 ship flags, 42 galley flags and several pennants were installed. With the development of the fleet, the number of signals also increased. In 1773, the signal book contained 226 reports, 45 night and 21 fog signals.

In 1779, a Russian mechanic invented a “spotlight” with a candle and developed a special code for transmitting signals. In the 19th - 20th centuries. further development was received by the means of light communication - lanterns and searchlights.

Currently, the flag table of the Naval Code of Signals contains 32 alphabetic, 10 numeric and 17 special flags.

PHYSICAL BASIS OF TELECOMMUNICATION

At the end of the 20th century, widespread telecommunication - the transmission of information by means of electrical signals or electromagnetic waves. Signals go through communication channels - wires (cables) or without wires.

All methods of telecommunication - telephone, telegraph, telefax, Internet, radio and television are similar in structure. At the beginning of the channel there is a device that converts information (sound, image, text, commands) into electrical signals. Then these signals are converted into a form suitable for transmission over long distances, amplified to the desired power and "sent" to cable network or radiate into space.

On the way, the signals are greatly weakened, so intermediate amplifiers are provided. They are often built into cables and put on repeaters (from lat. re - a prefix indicating a repeated action, and translator - "carrier"), transmitting signals via terrestrial communication lines or via satellite.

At the other end of the line, the signals enter a receiver with an amplifier, then they are converted into a form convenient for processing and storage, and, finally, they are again converted into sound, image, text, commands.

WIRED COMMUNICATION

Before the advent and development of radio communications, wired communication was considered the main one. By purpose, wired communication is divided into:

Far - for inter-regional and inter-district communication;

Internal - for communication in the settlement, in industrial and office premises;

Service - to manage the operational service on communication lines and nodes.

Wired communication lines are often interfaced with radio relay, tropospheric and satellite lines. Due to its great vulnerability (natural influences: strong winds, snow and ice sticking, lightning discharges or human criminal activity), wired communication has disadvantages in application.

TELEGRAPH COMMUNICATION

Telegraph communication is used to transmit alphanumeric information. Auditory telegraph radio communication is the simplest type of communication, which is economical and noise-immune, but its speed is low. Direct-printing telegraph communication has a higher transmission rate and the ability to document received information.

In 1837 S. Morse developed and supplemented Schilling's idea. He proposed a telegraphic alphabet and a simpler telegraph apparatus. In 1884, the American inventor Morse put into operation the first writing telegraph line in the United States between Washington and Baltimore, 63 km long. Supported by other scientists and entrepreneurs, Morse achieved a significant distribution of his apparatus not only in America, but also in most European countries.

By 1850, Russian scientist Boris Semenovich Jacobi

(1801 - 1874) created a prototype of the world's first telegraph apparatus with direct printing of received messages.

The principle of operation of the writing electromagnetic telegraph apparatus is as follows. Under the action of current pulses coming from the line, the armature of the receiving electromagnet was attracted, and in the absence of current, it was repelled. A pencil was attached to the end of the anchor. In front of him, a matte porcelain or faience plate moved along the guides with the help of a clockwork.

During the operation of the electromagnet, a wavy line was recorded on the plate, the zigzags of which corresponded to certain signs. A simple key was used as a transmitter, closing and opening the electrical circuit.

In 1841, Jacobi built the first electric telegraph line in Russia between the Winter Palace and the General Staff in St. Petersburg, and two years later a new line to the palace in Tsarskoye Selo. Telegraph lines consisted of insulated copper wires buried in the ground.

During the construction of the Petersburg-Moscow railway, the government insisted on laying an underground telegraph line along it. Jacobi proposed to build overhead line on wooden poles, arguing that it is impossible to guarantee the reliability of communication over such a long distance. As expected, this line, built in 1852, did not last even two years due to imperfect insulation and was replaced by an air line.

Academician carried out major works on electrical machines, electrical telegraphs, mine electrical engineering, electrochemistry and electrical measurements. He opened new way electroplating.

The essence of telegraph communication is the representation of a finite number of symbols of an alphanumeric message in the transmitter of a telegraph apparatus by the corresponding number of combinations of elementary signals that differ from each other. Each such combination, called a code combination, corresponds to a letter or number.

The transmission of code combinations is usually carried out by binary alternating current signals, most often modulated in frequency. When receiving, the electrical signals are converted back into characters and these characters are registered on paper in accordance with the accepted code combinations.

Telegraph communication is characterized by reliability, speed of telegraphy (transmission), reliability and secrecy of the transmitted information. Telegraph communication is developing in the direction of further improvement of equipment, automation of the processes of transmitting and receiving information.

TELEPHONE COMMUNICATIONS

Telephone communication is intended for conducting oral negotiations between people (personal or official). When driving complex systems Air defense, railway transport, oil and gas pipelines use operational telephone communication, which ensures the exchange of information between the central control point and controlled objects located at a distance of up to several thousand km. It is possible to record messages on sound recording devices.

The telephone was invented by an American on February 14, 1876. Structurally, Bell's telephone was a tube with a magnet inside. A coil with a large number of turns of insulated wire is put on its pole pieces. A metal membrane is placed against the pole pieces.

Bell's handset was used to transmit and receive speech sounds. The subscriber's call was made through the same handset using a whistle. The range of the phone did not exceed 500 m.

A miniature color television camera equipped with a microlight turns into a medical probe. Introducing it into the stomach or esophagus, the doctor examines what he could previously see only during surgery.

Modern television equipment makes it possible to control complex and harmful productions. The operator-dispatcher on the monitor screen monitors several technological processes simultaneously. A similar task is solved by the operator-dispatcher of the road safety service, following the traffic flows on the roads and intersections on the monitor screen.

Television is widely used for surveillance, reconnaissance, control, communications, command and control, in weapon guidance systems, navigation, astro-orientation and astro-correction, for monitoring underwater and space objects.

In the missile forces, television makes it possible to control the preparation for launch and the launch of missiles, and to monitor the condition of units and assemblies in flight.

In the Navy, television provides control and surveillance of the surface situation, an overview of the premises, equipment and actions of personnel, the search and detection of sunken objects, bottom mines, and rescue operations.

Small-sized television cameras can be delivered to the reconnaissance area using artillery shells, radio-controlled unmanned aircraft.

Television has found wide application in simulators.

Television systems operating in combination with radar and direction-finding equipment are used to provide air traffic control services at airports, flights in adverse weather conditions and blind landing of aircraft.

The use of television is limited by insufficient range, dependence on weather conditions and illumination, and low noise immunity.

Trends in the development of television - expanding the range of spectral sensitivity, the introduction of color and surround television, reducing the weight and dimensions of the equipment.

VIDEO TELEPHONE COMMUNICATION

Video telephony - the combination of telephone communication and slow-motion television (with a small number of scan lines) - can be carried out via telephone channels. It allows you to see the interlocutor and show simple still images.

FELDJEGERSKO - POSTAL SERVICE

Delivery of documents, periodicals, parcels and personal correspondence is carried out using courier and mobile communications: aircraft, helicopters, cars, armored personnel carriers, motorcycles, boats, etc.

CONNECTION QUALITY

The quality of communication is determined by the totality of its interrelated basic properties (characteristics).

Timeliness connections- its ability to ensure the transmission and delivery of messages or negotiation at a given time - is determined by the time of deployment of nodes and communication lines, the speed of establishing communication with the correspondent, the speed of information transfer.

Communication Reliability- its ability to work without fail (stably) for a certain period of time with the reliability, secrecy and speed specified for these operating conditions. The communication reliability is significantly affected by the noise immunity of the communication system, lines, channels, which characterizes their ability to function under the influence of all types of interference.

Communication reliability- its ability to ensure the reception of transmitted messages with a given accuracy, which is estimated by the loss of reliability, that is, the ratio of the number of characters received with an error to the total number of transmitted ones.

In conventional communication lines, the loss of reliability is at best 10-3 - 10-4, so they use additional technical devices to detect and correct errors. In automated control systems of the developed countries of the world, the norm of reliability is 10-7 - 10-9.

Communication stealth characterized by the secrecy of the very fact of communication, the degree of identification of the distinguishing features of communication, the secrecy of the content of the transmitted information. The secrecy of the content of the transmitted information is ensured through the use of encryption equipment, encryption, and coding of transmitted messages.

PROSPECTS FOR THE DEVELOPMENT OF COMMUNICATIONS

At present, all kinds and types of communication and the corresponding technical means are being improved. In radio relay communication, new sections of the microwave frequency range are used. In tropospheric communications, measures are taken against communication disruptions due to changes in the state of the troposphere. Space communications are being improved on the basis of "stationary" relay satellites with multiple access equipment. Optical (laser) communication is being developed and put into practice, primarily for the transmission of large amounts of information in real time between satellites and spacecraft.

Much attention is paid to the standardization and unification of blocks, assemblies and elements of equipment for various purposes in order to create unified communication systems.

One of the main directions for improving communication systems in developed countries is to ensure the transmission of all types of information (telephone, telegraph, facsimile, computer data, etc.) in a converted discrete-pulse (digital) form. Digital communication systems have great advantages in the creation of global communication systems.

LITERATURE

1. Computer science. Encyclopedia for children. Volume 22. M., "Avanta +". 2003.

2. At the origins of television. The newspaper "Physics", No. 16 for 2000

3. Craig A., Rosni K. Science. Encyclopedia. M., Rosman. 1994.

4. Kyandskaya-, On the question of the world's first radiogram. The newspaper "Physics", No. 12 for 2001

5. Morozov invented and for which G. Marconi received a patent. The newspaper "Physics", No. 16 for 2002

6. MS - DOS - no question! Editing and publishing center "Tok". Smolensk. 1993.

7. Reid S., Farah P. History of discoveries. M., Rosman. 1995.

8. Soviet military encyclopedia. M., Military publishing house of the Ministry of Defense. 1980.

9. Technique. Encyclopedia for children. Volume 14. M., "Avanta +". 1999.

10. Turov military connection. Volume 1,2,3. M., Military publishing house. 1991.

11. Wilkinson F., Pollard M. Scientists who have changed the world. M., "Word". 1994.

12. Urvalov television equipment. (ABOUT). The newspaper "Physics", No. 26, 2000

13. Urvalov electronic television. The newspaper "Physics", No. 4, 2002

14. Fedotov schemes by O. Lodge and G. Marconi. The newspaper "Physics", No. 4, 2001

15. Physics. Encyclopedia for children. Volume 16. M., "Avanta +". 2000.

16. Hafkemeyer H. Internet. Journey through the worldwide computer network. M., "Word". 1998.

17. At the origins of radar in the USSR. M., "Soviet radio". 1977.

18. Shmenk A., Vetien A., Kete R. Multimedia and virtual worlds. M., "Word". 1997.

Foreword ... 2

From the history of communications ... 3

Communication classification … 5

Signal communication … 6

The physical basis of telecommunications ... 7

Wired … 7

Telegraph communication ... 8

Telephony … 10

Telecode communication … 12

Internet … 12

Optical (laser) communication … 14

Fax … 14

Radio communication ... 15

Radio relay communication … 17

Tropospheric communications … 17

Ionospheric radio communication ... 17

Meteor radio communication ... 17

Space communications … 18

Radar … 18

Television communications ... 21

Video telephony … 24

Courier-postal communication ... 24

Communication quality … 25

Prospects for the development of communications ... 25

Literature ... 26

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Computer layout: Press Boris

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