SU866759A2 - Communication channel quality control device - Google Patents

Description

The invention relates to radio engineering and can be used in systems · data transmission.

According to the main author. St. No. 634463 _ it is known a device for monitoring the quality of a communication channel containing a comparator, the first input of which is connected to the output of the integrator, the second input - with the first output of the chronizer,. _ a counter of information symbols, the output of which is connected to the first inputs of the first and second comparison elements, respectively, the delay element and the OR element, while the second output of the chronizer is connected to 15 second inputs of the first and second comparison elements, the output of each of which is connected to the corresponding inputs OR element and the input of the delay element, the output of which is connected 20 to the first input of the information symbol counter, the second input of which is connected to the output of the comparator! 1J.

However, in the known device, insufficient accuracy of control.

The purpose of the invention is to increase the accuracy of control.

To achieve this goal, a device for monitoring the quality of a communication channel containing a comparator, θ the first input of which is connected to the output of the integrator, the second input to the first output of the chronizer, an information symbol counter, the output of which is connected to the first inputs of the first and second comparison elements, respectively , a delay element and an OR element, while the second output of the chronizer is connected to the second inputs of the first and second comparison elements, the output of each of which is connected to the corresponding inputs of the OR element and during the delay element, the output of which is connected to the first input of the information symbol counter, the second input of which is connected to the output of the comparator, a digital-to-analog converter and a pulse counter are introduced, the output of the OR element being connected to the input of the pulse counter, the outputs of which are connected to the inputs of the digital-to-analog converter, the output connected to additional input of the comparator.

The drawing shows a structural electrical diagram of the proposed device.

The device contains a comparator 1, integrator 2, chronizer 3, counter

4, comparison elements 5 and 6, delay element 7, OR element 8, pulse counter 9, digital-to-analog converter 10.

The device operates as follows.

In the initial state, the threshold of the comparator 1 is in an arbitrary state within the selected values. Upon receipt of a mixture of a useful signal in the form of a sequence of pulses and noise, the following cases of operation of the device are possible:

about . a) high-quality communication channel, i.e. the number of insertions and disappearances caused by the propagation in the communication channel does not exceed the norm specified by elements 5 and 6 of the comparison. The threshold of the comparator 1 is such that it does not lead to an increase in the number of insertions or disappearances. There are no pulses from the output of the OR 8 element. The comparator threshold remains unchanged. The channel is high-quality, at the output of the element OR - Oj

b) the communication channel is high-quality, but the threshold of the comparator 1 is such that the number of inserts, or the number of losses due to a non-optimal threshold,> exceeds the norm. An impulse will appear at the output of the OR 8 element, giving false information that the channel is of poor quality (since in fact the channel is high-quality, but the comparator threshold is incorrectly set). The pulse from the element OR 8 It is applied to the pulse counter 9, which counts the number of pulses received at the input, the number of pulses is converted by a digital-analog converter 10 into an analog signal that sets the threshold of the comparator 1. Each pulse received at the input of the counter 9 pulses increases the threshold level by one step comparator 1, Level rise within the selected threshold limits will occur until the threshold approaches the optimal signal-to-noise ratio existing in the channel. At this moment, at the output of the OR element 8, the pulses will disappear, the pulses to the input of the counter 9 will stop, and the threshold level of the comparator 1 will stop at the reached value. The channel is high-quality, at the output of the element OR 8-0, '

c) poor-quality communication channel, i.e. in a useful message arriving, the number of insertions or missing is more than normal. From the output of the element OR 8, pulses begin to arrive at the input of the counter 9 pulses. The device operates similarly to case (b) to the maximum threshold and until the counter 9 is full. The next pulse resets the counter 9 and the threshold level starts to rise again from the lower level. Moreover, for all threshold values, single pulses are transmitted from the output of the OR element, carrying information about a poor-quality channel.

Thus, in the proposed device, in comparison with the known, increases the accuracy of control.

Claims (1)

The invention relates to radio engineering and can be used in data transmission systems. On the main auth, sv. 634463, a device for controlling the quality of the communication channel is known, the comparator, the first input of which is connected to the integrator output, the second input — the counter of information symbols, the output of which is connected to the first inputs of the first and second comparison elements, the delay element and the element — to the first output of the chroniser. OR, while the second output of the chronizer is connected to the second inputs of the first and second comparison elements, the output of each of which is connected to the corresponding inputs of the OR element and the input delay element, output Which is connected to the first input of the counter of information symbols, the second input is connected to the output of the comparator11. However, in the known device the accuracy of the control is not complete. The purpose of the invention is to increase the accuracy of control. To achieve this goal, the device for controlling the quality of the communication channel, which contains a comparator, has a first input connected to the integrator output, a second input to the first output of the chronizer, an information character counter, the output of which is connected to the first inputs of the first and second comparison elements, respectively. delays and an OR element, while the second output of the chronizer is connected to the second inputs of the first and second comparison elements, the output of each of which is connected to the corresponding inputs of the OR element and input a delay element whose output is connected to the first input of the counter of information symbols, the second input of which is connected to the comparator output, is entered a digital-to-analog converter and a pulse counter, the output of the OR element is connected to the input of a pulse counter, the outputs of which are connected to the inputs of the digital-analog converter, the output connected to additional input of the comparator. The drawing shows a structural electrical circuit of the proposed device. The device contains a comparator 1, an integrator 2, a chronizer 3, a counter 4, elements 5 and 6 of the comparison, a delay element 7, an OR element 8, a pulse counter 9, a digital-analog converter 10. The device operates as follows. In the initial state, the threshold of the comparator 1 is in an arbitrary state within the limits of the selected values. Upon receipt of a mixture of a useful signal in the form of a sequence of pulses and noise, the following cases of device operation are possible:. a) communication channel quality, i.e. the number of inserts and disappearances due to the propagation in the communication channel does not exceed the norm set by elements 5 and 6 of the comparison. The pore of comparator 1 is such that it does not lead to an increase in the number of inserts or gaps. From the output of the element OR 8 no pulses. The comparator threshold remains unchanged. The channel is qualitative, at the output of the element OR - Oj b) the communication channel is qualitative, but the threshold of comparator 1 is such that the number of inserts or the number of interruptions due to the non-optimal threshold exceeds the norm. At the output of the element OR 8, a Wits impulse gives false information that the kansh is of poor quality (since the quality of the comparator is actually good, but the comparator threshold is incorrectly set). Pulse from the element OR 8 It is fed to the pulse counter 9, which counts the number of pulses received at the input, the number of pulses is converted by a digital-to-analog converter 10 to an analog signal that sets the threshold for the comparator 1. Each pulse received at the input of the counter 9 pulses raises the level of the threshold by one level comparator The level rise within the selected threshold limits will occur until the threshold approaches the optimum for the existing signal-to-noise ratio on the channel. In this MOivieHT, at the output of the element OR 8, the pulses will disappear, the pulses at the input of the counter 9 will stop and the threshold level of the comparator 1 will stop at the reached value. The quality channel at the output of the element OR 8-0, c) the communication channel is of poor quality, i.e. In the incoming useful message, the number of inserts or disappears is higher than the norm. From the output of the element OR 8, pulses are fed to the input of the counter 9 pulses. The device operates as in case (b) to the maximum threshold value and before the counter 9 is filled. The next pulse resets counter 9 and the threshold level starts to increase again from the lower level. Moreover, for all values of the threshold from the output of the OR element, there are single pulses that carry information about the poor quality channel. Thus, in the proposed device, in comparison with the known, the accuracy of the control is improved. Claims Device for monitoring the quality of the communication channel by aut. St. No. 634463, characterized in that, in order to increase the control accuracy: a digital-to-analog converter and a pulse counter are entered, the output of the OR element is connected to the input of a pulse counter, the outputs of which are connected to the inputs of the digital-analog converter, the output connected to the auxiliary input of the comparator. Sources of information taken into account in the examination 1. USSR author's certificate 634463, cl. H 04 B 3/46, 1977 (prototype).