RU2342781C2 - Device for amplitude and frequency distortions compensation in line link using 2d metric domain - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: invention relates to electrical communications and may be used for compensating signal distortions in transmission system lines. The device comprises a control generator, transmission line, corrector, regulator unit, frequency switch, comparing unit, "Startup" key, sync pulse generator, two AND elements, two meters, switching element, delay element, switch, three registers, two analog-digital converters, in-liner storage, storage device and control unit.

EFFECT: fast correction of signal distortions in data transmission systems.

2 dwg

Description

The invention relates to telecommunications and can be used to compensate for distortion of the signal paths of transmission systems. The technical result is to increase the speed of correction of signal distortion in the information transmission system.

A device for automatically correcting the amplitude-frequency distortion of the transmission system paths, comprising a control generator, a communication path, a corrector, a matching unit, a multiplier, a reference generator, a frequency switch, a control unit, two comparators, a reference frequency filter, an intermediate frequency filter, three rectifiers, control unit of the reference generator, a subtraction unit, a synchronization unit and two control units (see USSR author's certificate No. 1020995, class H04B 3/04, publ. 05/30/1983, bull. No. 20).

The disadvantage of this device is the low accuracy of the distortion correction of the frequency response.

The closest in technical essence to the claimed invention is a device for automatic correction of amplitude-frequency distortions of the paths of information transmission systems, comprising a control generator, a communication path, a corrector, a matching unit, two multipliers, a reference generator, a block of regulators, a frequency selector, a comparator, two integrators , two quadrators, an adder, a gating unit, a normalizing unit, a power meter, a delay line, a clock generator and a phase shifter (see RF patent No. 2234188, class H04 3/04, 1/62, publ. 10.08.2004, Bull. №22).

The disadvantage of this device is the low reliability of the correction of the signals of the information transmission system arising from imperfections in the frequency characteristics of the communication path.

This disadvantage is due to the fact that to assess the degree of signal distortion, one attribute space is used, consisting of attribute functions in the form of functions of the mutual difference between the reference and the controlled signals.

The essence of the invention lies in the fact that the reliability of assessing the degree of signal distortion is achieved by recognizing the image of a controlled and investigated state diagram (DS) in two planes.

To increase the accuracy of the AFC correction, the investigated output signal from the communication path is divided into two signals that differ from each other by a quarter of the period. These two studied signals form a closed figure in a Cartesian coordinate system. This figure is called a state diagram (DS) (figure 2).

The resulting DS consists of coordinate points that are obtained by comparing two discrete signals, in addition, each DS point is determined in the polar coordinate system by measuring the vector length (from the origin to a specific point) and the angle between the vector and the X axis.

The degree of signal distortion can be estimated by not measuring the deviation of the parameters from the nominal values, but by analyzing the shape of the DS.

The objective of the invention is to increase the reliability of the diagnosis of REI through the use of two characteristic spaces. In this case, it is assumed that the signal distortion is estimated in two stages:

at the first stage, receive N samples of measurement results during the duration T of one signal period (and not spend time T for each sample, as is implemented in the prototype);

at the second stage, during time T, to carry out the identification of the obtained signal estimation results with the determination of signal distortion in the subbands of the passband of the communication path.

Figure 1 presents the functional diagram of the device.

A device for compensating amplitude-frequency distortions of linear paths comprises a Start button 1, a clock pulse generator 2, a first counter 3, a key 4 element, a first 5 I element, a control 6 generator, a communication path 7, a corrector 8, a key 9, an element 10 delays, two analog-to-digital converters 11 and 12, two registers 13 and 14, block 15 of the RAM of the evaluation results, the second element 16 AND, the second counter 17, read-only 18 memory, comparison unit 19, the third 20 register, control unit 21, 22 frequency switch, block 23 regulators.

The device operates as follows.

Before starting work, the block 15 of the RAM of the evaluation results, as well as the registers 13 and 14 are in the initial (zeroed) state. In the cells of the memory unit 18, information is recorded on the amplitude-frequency distortion of the signal in various subbands.

When the “Start” button 1 is pressed, the voltage is applied to the input of the gate generator 2, the pulses are sent from the first output to the first input of the first 5 And elements and to the first input of the second 16 And elements, and from the second output pulses are sent to the first 3 counter, which the first pulse switches the key 4 element to position "1". From the output of the key 4 element voltage is supplied to the second input 5 of the first element I.

The investigated signal from the control 6 of the generator through the communication path 7 is supplied to the information input of the key 9. The voltage supplied from the starting 1 element through the open first 5 element And to the control input of the key 9, provides the passage of the values of the studied signal through the delay element 10, analog-digital converters 11 and 12 and further in converted form to the corresponding inputs of the registers 13 and 14. From the first outputs of the registers 13 and 14, the signals are fed to the input of the block 15 of the memory of the evaluation results.

When counting the N-th pulse from the output of the first counter 3, a signal is sent to the key 4 element, transferring it to the state "2", after which the first counter 3 is reset. The device is transferred from the signal evaluation mode to the analysis of results. In this case, the first element 5 And closes, and the voltage from the key 4 element opens the second element 16 And, the output of which clock pulses are fed to the input of the second 17 counter. The output of the second counter 17 is connected to the control input of the comparison unit 19. The first information input of the comparison unit 19 is connected to the output of the constant 18 storage device, and the second information input of the comparison unit 19 is connected to the output of the main memory unit 15 of the evaluation results.

Code sequences with a repetition rate of N / T provide a sequential comparison of the contents of the cells of the RAM block 15 with the information recorded in the corresponding cells of the permanent 18 storage device. When the cells coincide, the logical “unit” signal enters the third 20 register. After analyzing the state of the last (N × N) -th memory cell of block 15 in the third 20 register, the maximum number of logical “units” will correspond to information on the amplitude-frequency distortions of the signal in a particular frequency range recorded in the 18 permanent memory.

The output of the third 20 register is connected to the information input of the control unit 21. The output of the control unit 21 receives a control signal to the input of the frequency switch 22, providing a choice of a specific frequency range. The frequency switch 22 is set to its initial state from the output of the communication path 7. From the output of the frequency switch 22, a voltage appears with the level of a logical unit, which ensures the connection of the corresponding controller of block 23 to the corrector.

Since the N-th pulse at the output of the second counter 17 corresponds to the N-th pulse counted by the first counter 3 at the second stage of operation of the device, from the output of the first counter 3 the key 4 element is switched to position “1”. The device switches to its original position and works in the first mode - signal evaluation.

The proposed diagnostic method using two feature spaces allows to increase the reliability of the correction of amplitude-frequency distortions in the subbands of the passband of the communication path.

Claims (1)

A device for compensating amplitude-frequency distortions in linear paths, comprising a serially connected control generator, a communication path and a corrector, the control input of which is connected to the output of the control unit, a frequency switch, the output of which is connected to the control input of the control unit, and the first input of the frequency switch is connected to an output of the communication path, characterized in that an additional comparison unit, a sequentially connected “Start” button, a clock pulse generator, the first output of which o connected to the first inputs of the first and second elements AND, and the second output of which is connected to the input of the first counter, the output of which is connected to the input of the key element, key, delay element, first analog-to-digital converter, first register, RAM block, first information input which is connected to the output of the first register, and the second information input to the output of the second register, the second analog-to-digital converter, the second counter, the output of which is connected to the control input of the comparison unit, the first inf the irrational input of which is connected to a read-only memory device, and the second information input is connected to the output of the random access memory block, the control unit, the input of which is connected to the output of the third register, the input of which is connected to the output of the comparison unit, while the second input of the frequency switch is connected to the second output of the block control, the input of the second register is connected to the output of the second analog-to-digital Converter, the input of which is connected to the output of the key, the control input of which is connected to the output of the first element And, the second the first input of which is connected to the first output of the key element, the second output of which is connected to the second input of the second element And, the output of which is connected to the input of the second counter, while the test signal from the control generator is fed through the communication path to the information input of the key, and the voltage supplied to the key control input provides the passage of the values of the signal under investigation through the delay element, the first and second analog-to-digital converters, and then in a converted form to the inputs of the corresponding registers , the outputs of which the signals are fed to the inputs of the RAM block, and the first output of the control unit is the output of the device.

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