SU1401626A1 - System for radio communication with mobile objects - Google Patents

Abstract

This invention relates to a radio technique. The purpose of the invention is to increase the capacity of the radio channel. When the specified time is set, the message, depending on the system load, goes through the free keys of free access or address polling to the buffer storage unit, which forms a message for transmission to the radio channel in accordance with the exchange protocol. When exchanging messages between a transceiver station and mobile communication objects, the channel load varies depending on the flight phase and information. digital radio subscriber activity. The counter of moving objects controls the number of objects and gives this number to the system load counter. Depending on the number of objects and the number of message requests, the system uses dynamic information. messaging and radio channel management algorithms. By analyzing the status and loading of the channel, the ground station determines the number of collisions of messages in the radio channel. To avoid collisions while simultaneously transmitting messages to several objects, the carrier is monitored during exposure to the onboard receiver. A message is transmitted when the radio channel is free. For separation in time of the exit moments of the mobile objects in the on-board device, a carrier frequency analyzer and a pseudo-random delay are introduced, which provide a delay in the transmission of messages from mobile objects. 2 Il. i cl

Description

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The invention relates to a radio communication technique and can be used for organizing digital communication in air-to-ground automated data exchange systems in accordance with the priority modes adopted in the system for transmitting messages between airborne and ground digital communication subscribers.

The purpose of the invention is to increase the capacity of the radio channel.

FIG. 1 is a functional diagram of a ground transceiver station; in fig. 2 - the onboard transceiver station is functional.

The ground transceiver station contains a receiver 1, demodulator 2, a decoder for 3 messages, a buffer register 4 of addresses of moving objects, the first element 5, a decoder 6 for message priorities, block 7 for timers for priority messages, block 8 for priority message registers, a switch-distributor 9 “bnheny”, counter 10 of the number of moving objects, counter 11 system loading, generator 12 clock pulses of free access, generator 13 time windows, generator 14 clock pulses of address polling, delay line 15, second ele Ment 16, free access key 17, data output unit 18, address interrogation key 19, buffer storage unit 20, resend number counter 21, reset pulse generator 22, data recording unit 23, modulator 24 and transmitter 25.

The airborne transceiver station of a mobile communication system with mobile objects contains an antenna switch 26, receiver 27, demodulator 28, address descrambler 29, mode descrambler 30, data recording unit 31, data output block 32, message register block 33, message priority encoder 34, switch -distributor 35 messages, free access key 36, generator of 37 clock pulses, address inquiry key 38, time relay 39, delay line 40, random number generator 41, modulator 42, transmitter 43, carrier frequency analyzer 44, generator 45 p sevdrandom incident. .

The radio system with moving objects operates as follows.

The messages received by the ground receiver 1 from the air-to-ground channel are demodulated in demodulator 2 and sent to the decryptor 3 messages, which is connected to the buffer register 4 addresses of mobile objects, where, according to the exchange protocol adopted in the system, the received message is identified addresses with addresses of moving objects, stored in the buffer register 4 addresses of moving objects. NRI

the coincidence of the address of the moving object with the address stored in the list to the element 5 is fed to the control signal from the buffer register 4 of the addresses of the moving objects and the message goes to the decryptor 6 of the message priorities. The ranking of messages by priority for incoming informational messages in accordance with the urgent categories received in the system of radio communication with mobile objects is carried out by means of shift registers of messages, in the lower order of which is initially recorded as "1, which corresponds to the absence of messages. When messages arrive in the radio channel in registers, the messages of the corresponding queues are shifted and priority timers are started, the number of which is determined by the number of received message priorities in accordance with the exchange protocol, which

0 and control the time the messages are in the queue of the appropriate urgency category. The priority message timers block 7 determines the information aging time, and if the message has not been transmitted to the communication channel for a certain period of time, then it is erased or the buffer storage unit 20 sends a request to retransmit the message.

When keeping the specified time

The Q message, depending on the system load, is received via the free access keys 17 or the address poll keys 19 to the buffer storage unit 20, which generates a message for transmission to the radio channel in accordance with

5 exchange protocol.

When exchanging messages between the ground transceiver station and mobile communication objects, the channel load varies depending on the flight phase and information activity of subscribers.

0 digital radio. The counter 10 of the number of moving objects continuously monitors the number of objects and outputs this number to the counter 11 of the system load, which determines the load on the communication channel. Depending on the number of mobile objects and the number of radio channel message inquiries, the system uses dynamic message exchange and radio channel control algorithms. When the channel is loaded low, the free access mode from moving objects is used, and when the channel loading is exceeded, the system automatically switches to address scanning of moving objects.

By analyzing the state and loading of a radio channel in a communication system with mobile objects, the ground transceiver station determines the number of collisions of messages in the radio channel.

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and, when this number exceeds the maximum permissible, the system goes into address polling mode in order to streamline the operation of the air-ground data transmission channel. In order to avoid collisions, when several messages are transmitted by several objects, the carrier is monitored during exposure to the onboard receiver of the message service part and the prepared message is transmitted only when the radio channel is free. In order to postpone the time when the mobile objects entered the communication while they found that the radio channel is free, a carrier frequency analyzer and a pseudo-random delay generator were inserted into the airborne transceiver device, which provide a delay for the transmission of messages from mobile objects.

With a low system load, the system load counter 11 generates a control signal to the generator of 12 free-access clock, which sets the system operation cycle via the free access key 17 in the free access mode.

When the system load of the boundary load is exceeded, the system load counter issues a control signal for switching the address polling through the trigger window generator 14, which sets the system operation cycle via the address polling key 19 in the address poll mode. In the address polling mode, the initiator of communication can only be a ground transceiver station, which, according to the list of moving objects stored in the 4-address buffer register, periodically polls moving objects, and they cannot interrupt the polling cycle on their own initiative and transmit an alarm message. Therefore, it is possible to promptly transfer emergency (emergency) messages from mobile communication objects through a digital radio channel. If the mobile objects have formed a message for transmission and have found that the radio channel is free, then they will inform the remaining mobile objects about the beginning of the transmission cycle and randomly distribute the order of their own transmission in this cycle. Each of the moving objects, using the carrier signal in the radio channel and synchronization pulses, calculates the sum of transmission periods (without differentiating them into successful and unsuccessful) and free priority periods (equal to one time window). If this amount coincides with the value of the established priority, the mobile object starts transmitting its own packet.

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Let us consider the features of using the system to transmit alarm messages from mobile objects in the free access mode.

Let, for a time equal to the threshold of limiting T, be generated by issuing from the buffer storage unit 20 a corresponding command to open E windows for sending alarm messages from mobile objects in the free mode.

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 access. These windows are equally spaced apart from each other by T / E. The duration of each window to is generally a random variable equal to the sum of the K transmission periods and the free period, where K is a constant value, moreover. Thus, the time interval between two adjacent teams for the formation of free access windows consists of two parts: the first of them is the "window

0 for transmission from mobile objects of alarm messages in the free access mode, to duration, and the second for transmission of messages from the ground transceiver in the address polling mode. The communication system with mobile objects allows organizing the transmission of messages for opening windows in free access mode, as well as in an address poll of mobile communication objects using the generator 13 of the time window, delay line 15 and AND 16 elements that generate control signals to the buffer storage unit 20 for transmitting messages to moving objects on opening and closing windows. The generator of 22 reset pulses in block 8 of the priority message registers clears the processed messages on the corresponding priority registers. The counter 21 of the number of questioning controls the number of transmitted messages and the number of confirmations received from mobile

 objects, and transmits control signals to the system load counter 11. Next, the buffer storage unit 20 receives the message to be transmitted from the data output unit 18, generates

The service and information part of the message is transmitted to the serially connected modulator 24 and transmitter 25, where, in accordance with the modulation method used, the message is transmitted to the radio channel for mobile objects. On board, the receiver is in receive mode at a frequency I l (polling message transmission frequency from a ground transceiver station). After the message passes through the antenna switch 26. receiver 27, demod.ch 5 tor 28, it enters the address 29, where the address taken in communication with the address of the mobile is identified, the address is stored. Next, the message is transmitted to the mode decoder 30, where the received service message is decrypted and it is determined in which mode the system works, and the message information part is recorded in the data recording unit 31. After decoding the mode sign, a control signal is sent to the free access keys 36 or address poll keys 38, which operate under the control of the clock pulse generator 37. If the data output unit 32 has generated a message; for transmission, it is recorded in the message buffer register unit 33 and then goes to the message encoder 34, where the service part of the message is formed and priority is determined depending on the priority level of digital communication subscribers. Next, the message arrives at the switch-distributor 35 of messages, which, depending on the priority level, rang-: them in sequence for transmission. The messages are then transmitted to free access keys 36 or address polling keys 38, depending on the mode of operation of the system, which is determined by the ground transceiver station.

Claims (1)

Invention Formula The radio communication system with mobile objects, in the ground transceiver 1st station, serially connected receiver and demodulator, serially connected transmitter and modulator, data recording unit, data output unit, first and second elements And, in the onboard transceiver station serially connected antenna a switch, a receiver, a demodulator and an address de-converter that are connected in series to a modulator and a transmitter, the output of which is a yo-dip with the input of the antenna switch, a data recording unit and a data output unit, characterized in that, in order to increase the capacity of the radio communication channel, serially connected message transmitter, a buffer register of addresses of mobile objects are entered into the ground transceiver station, the count of the number of objects, the load counter of the system. , free access clock, free access key and buffer memory, jj block, serially connected time window shaper and address poll clock pulse generator, delay line, key address th polling serially connected n-bit bus descrambler messages priority register block priority messages consisting of n priority registers, and the switch-valve messages, timers block prio0 0 five 0 five 0 five 0 five of received timers, a counter of the number of reselling and a generator of reset pulses, the output of the demodulator connected to the input of the message decoder, the output of which is connected to the first input of the first element And, the second output of the buffer register of addresses of mobile objects connected to the second input of the first element And, the output of which is connected to the input of the message priority decoder, the output of which is connected by an n-bit to the input of the block of timers of priority messages, the output of which is connected by an n-bit bus to the control unit The first input of the priority message register block, the first output of the message distributor switch is connected to the information input of the free access key and the information input of the address poll, the output of which is connected to the second input of the buffer storage unit, and the second output of the registration switch box data, the output of the data output unit is connected to the third input of the buffer storage unit, the output of the count of reseps numbers is connected to the second input of the load counter ki system, the second output of which is connected to the input of the time window shaper, the second output of which is connected to the input of the delay line, the first output of which is connected to the first input of the second element And the output of the clock pulse generator of the address poll is connected to the second input of the second element And whose output is connected with the control input of the address interrogation key, the output of the delay line is connected to the fourth input of the buffer storage unit, the output of which is connected to the inputs of the modulator, the count of resend numbers and the generator The reset pulses, the output of which is connected by an n-bit bus to the reset input of the priority message register block, are entered into an onboard transceiver station by a message register block connected in succession by an n-bit width, a message priority encoder and a message distributor connected in series to a clock pulse generator , address polling key, time relay, delay line and random number generator, mode decoder, serially connected carrier frequency analyzer, n generator A random random delay and a free access key, the output of the address resolver is connected to the input of the mode decoder, the first output of which is connected to the input of the data recording unit, the second and third outputs of the mode decoder are connected to the second input of the address poll key and free access key, the output of the block data output connected by n-bit bus with the input of the register of messages, the output of the switch-distributor of messages is connected to the third input of the address polling key and to the third input of the free access key, the second output of the clock generator is connected to the fourth input of the free access key, the output of which is connected to the first input of the modulator, the output of the random number generator is connected to the second input of the modulator, the second output of the receiver is connected to the input of the carrier frequency analyzer.