SU1702387A1 - Communication system simulating device - Google Patents

Abstract

The invention relates to digital computing and can be used in simulating the operation of Cs systems. The purpose of the invention is to improve the accuracy of the simulation by taking into account the transmission time of the lowest priority messages over the communication channel. The device contains a message pulse generator, eight counters, seven AND elements, a delay element, five OR elements, three triggers, a random noise interference generator, two NOT elements, a high priority message generator. The device makes it possible to increase the accuracy of simulating the transmission of messages of different priority over a single communication channel by taking into account the transmission time of a communication of lower priority messages over a communication channel. 1 il.

Description

The invention relates to digital computing and can be used in modeling the operation of communication systems.

The purpose of the invention is to improve the modeling accuracy by taking into account the transmission time of a low priority message over a communication channel.

The drawing shows a block diagram of the device.

The device for simulating communication systems comprises a generator of 1 low priority message pulses, a counter of 2 low priority messages, setup input 3, the first element AND 4, a delay element 5, the first element OR 6, the first trigger 7, the generator 8 random interference pulses, the first element NOT 9, second 10, fifth and AND and fourth 12 elements AND, generator 13 impulses of high priority messages, second element NOT 14, third element AND 15, third 16, fourth 17 and second 18 elements OR, second 19 and third 20 triggers, the sixth 21 and the seventh 22 elements And, n first OR gate 23, the counter 24, the low priority message on the communication channel inlet schetchik25 low priority messages on communication channel input, the counter

26 high priority messages, counter

27 messages received in the communication channel, a counter of 28 direct messages, a counter of 29 distorted low-priority messages, a counter of 30 distorted high-priority messages.

Before the device starts working through its installation input on the installation inputs

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All the counters through the element OR 6 to the single input of the trigger 7 and through the elements OR 17 and OR 18 to the single inputs of the flip-flops 20 and 19 are fed a control signal that connects all the counters and sets the triggers 7, 19 and 20 to state 1 which allows the passage of signals through the AND 4 element.

Generator 1 generates a sequence of pulses that simulate the flow of low priority messages arriving at the input of the communication system. The number of pulses from the generator 1 is counted by counter 2. The pulse from generator 1 output passes through the open element 4 to the counter input of counter 24 , to the input of the element And 10, to the input of the element 5 of the delay and to the zero input of the trigger 7, which goes to state O, prohibits the passage of signals through the element 4, If at the output of the generator 13 priority messages there is no signal, then the drive from the output of the HE element 9 opens the AND 10 element and the pulse from the output of the AND 4 element enters the zero inputs of the flip-flops 19 and 20, switching them to the O state. Through the delay time (transmission time of one message) from the output of the delay element 5, the pulse through the element OR b sets the trigger 7 to state 1, which again allows the passage of signals through the element 4. Thus, the loss of low priority messages at the input of the communication channel due to the formation of a queue is simulated.

The generator 13 at random times generates pulses that simulate the flow of high priority messages. The number of these pulses is counted by the counter 26. The pulses from the output of the generator 13 also reach the inputs of the elements OR 16, 17 and 18, IE 9, AND 12,15. If the output of the generator 13 has a signal. then at the output of the element HE 9 there is no signal and the pulse from the output of the element AND 4 (the beginning of the low priority message) is denied to the zero inputs of the flip-flops 19 and 20, which remain in state 1. If the signal at the output of the generator 13 is absent, then the output of the element And 4 gets the opportunity to flow through the open element And 10 to the zero inputs of the flip-flops 19, 20, transfer them to the state O. In this case, the signals from the inverse outputs of the flip-flops 19 and 2 () open the elements And 21 and 22 and the pulse from exit element 5 delay (the end of messages low priority) gets the opportunity to enter the counting inputs of the counter 25, the counter 27 messages received

communication channel and counter 28 received messages. The pulse from the output of the delay element 5 through the elements OR 6 and OR 18 goes to the single input of the trigger 19, and through the elements OR 6 and OR 17 to the single input of the trigger 20, transferring these triggers to state 1 at the moment of the end of the transmission of the low priority message. If a pulse at the output of the generator 13 appears during the transmission of a low priority message, it will translate the triggers 19 and 20 and state 1 through the elements OR 17 and 18, and the elements 21 and 22 will be closed by the time the pulse appears at the output of the element 5 delays. Thus, information loss is simulated if a low priority message starts at the moment of the communication channel being filled with a higher priority message or if the higher priority message appears after the start, but before the end time of the low priority message.

The generator 8 and the elements 14, and 15 and 22 trigger 20 serve to simulate the effect of the error stream on the messages transmitted over the communication channel.

If a pulse at the output of generator 8 appears during the transmission of a low priority message, when trigger 20 is in state O, this pulse, arriving at the single input of trigger 20, translates it into state 1. This prevents the pulse from passing through the output of element 5 delays through element 22, which simulates the loss of a low priority message. The signal from the output of the generator 8, the input element NO 14, prohibits the passage of pulses from the generator 13, simulating the loss of messages of high and low priorities.

Claims (1)

Invention Formula A simulation system of a communication system comprising a low priority message pulse generator, the output of which is connected to the counting input of the low priority message counter and the first input of the first And element, the output of which is connected to the first input of the second And element, the zero input of the first trigger and the delay of the delay element whose output is connected to the first input of the first OR element, the output of which is connected to the single input of the first trigger, the direct output of which is connected to the second input of the first element AND, the gene ator pulses of high priority messages, the output of which is connected to the counting input of the high priority message counter, a first input of a second OR gate, a first input of NOT circuit whose output connected to the second input of the second element AND, the output of the second element is NOT connected to the first input of the third element AND, and the input of the second element is NOT and the first inputs of the fourth and fifth elements AND are connected to the output of the random interference generator, the output of the first element AND is connected to the counting input the low priority message counter at the input of the communication channel, the high priority message generator output is connected to the second input of the fourth And element, the output of which is connected to the counter input of the distorted message counter high The priority, the output of the first element And is connected to the counting input of the counter of distorted low priority messages, the low priority message counter at the input of the communication channel, the message counter, the installation inputs of all the counters and the second input of the first element OR are the installation input of the device, t is especially so that. in order to increase modeling accuracy by taking into account the transmission time of a low priority message over the communication channel, it additionally contains the sixth and seventh elements AND, the third, fourth and fifth OR elements and the second and third triggers, zero inputs of which are combined and connected to the output of the second element And, the output of the delay element is connected to the first the inputs of the sixth and seventh elements And, the second input of the sixth element And is connected to the inverse output of the second trigger, and the output of the sixth element AND is connected to the counting input of the low priority message counter at the input of the communication channel and the first input of the third OR element, the second input of which and the first input of the fourth OR element are connected to the output of the high priority message generator, and the output of the third OR element is connected to the counting input counter messages received in the communication channel, the output of the first the OR element is connected to the second input of the fourth OR element, the third input of which is connected to the output of the random noise generator, and the output of the fourth OR element is connected to the single input of the third trigger, the inverse output of which is connected to the second input of the fifth element AND and the second input of the seventh element AND whose output is connected to the first input of the fifth element OR, the second input of which is connected to the output of the third element AND, and the output of the fifth element OR is connected to the counting input of the counter of received messages, the output of the second element OR is connected to the unit the input of the second trigger, and the second input of the third element And is connected to the output of the generator of high priority messages.