SU1580387A1 - Device for modeling binary communication channel - Google Patents

Abstract

The invention relates to computing and can be used to model digital information channels. The purpose of the invention is to extend the functionality by reproducing errors, the statistics of which is described by the generalized Gilbert model built on the basis of Markov chains. This goal is achieved by introducing into the device an additionally controlled generator of random binary codes, memory blocks, and a delay element. The essence of the invention is based on the hardware simulation of the N-ary process of the binary communication channel states, the formation of a group of errors with a given probability in each state and their introduction into the information sequence of symbols. 2 Il.

Description

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The invention relates to computing and can be used to simulate digital information channels.

The purpose of the invention is to extend the functionality by reproducing errors, the statistics of which is described by the generalized Gilbert model built on the basis of Markov chains.

Figure 1 is a diagram of a device for simulating a binary communication channel; Fig. 2 is a schematic of a controlled random binary code generator.

The device contains a reference signal generator 1, a controllable generator of 2 random binary codes, (N + I) memory blocks 3, a delay element 4, a probability switch

5, trigger 6, adder 7 modulo two. Generator 2 includes generator 8 of a random pulse stream, element 9, pulse distributor 10, N converters 11 code — intensity of a random stream of pulses, block 12 for the formation of incompatible random events, encoder; 13, memory register 14.

The device works as follows.

Binary symbols of information sequence B, j are received at the first input of modulator 7 modulo 2. Error input to the information sequence H Bj} is performed by synchronously feeding modulo two to the second input of the distorting random sequence {EJ} formed at the direct output

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trigger 6. The synchronization of the sequences E-} and fB j is provided by using a common oscillator 1 of the reference signal setting the clock frequency of the source of binary information to be transmitted over the simulated communication channel.

The pulses of the generator 1 are fed to the synchronization input of the generator 2 random binary codes. On the first impulse of the generator 1 with probabilities P. , j e О, N-1, the binary code j is generated, which is fed to the address inputs of the group 3 memory blocks. | The outputs of the latter are called (N + 1) binary codes that define the current probability row P: ":, (j 1, N) of the transition of the communication channel to the new state and the probability: # errors during the current channel state connection.

At the same time, the generator pulses through delay element 4 arrive at the synchronization input of the probability switch 5. With probability B: # a polling pulse appears at the first output and with probability 1 - - Јj at the second output of the probability switch 5. At the direct output trigger 6, binary symbols Јo, 1} of the distorting sequence {E0t-j, synchronous with the elements of the information sequence B, -} are formed.

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sequences E0 |) and (B ;, implemented by adder 7, information sequence B, is endowed with errors, the statistics of which are given by the generalized Gilbert model.

The method of setting up the device is as follows.

In the first N blocks of 3 memories of the group, binary codes Xt «- are entered, the relative values of which are numerically equal to the corresponding elements of the probabilistic N-dimensional square matrix || P {, If (i, j 6 1, N) simulated channel

connections that are likely to cause errors. The index i means the number of the memory block, and

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The deck has the j-address at which the binary code of probability element P (. of the state change matrix of the simulated communication channel) is stored in the 1st memory block.

In (N4-1) -and block 3 of the memory of the group, binary codes of conditional probabilities of errors Ј .j are entered for each of the N possible states of the communication channel.

Claims (1)

Invention Formula A device for simulating a binary communication channel, comprising a reference signal generator, a probability switch, a trigger, a modulo two, the first output of a probability switch connected to a single trigger input, the zero input of which is connected to the second output of a probability switch, the first input and the modulo two adder output is, respectively, an information input and a device output, characterized in that, in order to extend the functionality by reproducing errors whose statistics is described by the generalized Gilbert model built on the basis of Markov chains, it additionally contains a controlled random binary code generator, (N + 1) memory blocks and a delay element, the output of the reference signal generator being connected to the polling input of the controlled random binary generator codes, the output group of which is connected to the address inputs (N + 1) of the memory blocks, the output group of each from 1 to N memory blocks is connected to the input group of the probability setting of the controlled random binary generator codes, respectively, the output group (N + + 1) of the memory block is connected to the probability setting inputs of a probability switch, whose information input is connected to the output of the reference signal generator through the delay element, the trigger output is connected to the second input of the adder modulo two.