SU842915A1 - Telemetering apparatus receiving device - Google Patents

Description

(54) RECEPTION TEMPERATURE SYSTEM. DEVICE

The invention relates to information measuring equipment and can be applied in telemetry, as well as in communication systems and telecontrol. A well-known telemeasuring system in which zero-side extrapolation is performed on the receiving side based on discrete readings of telemetry signals. The receiving device of this system contains in each channel a serially connected digital memory (memory) and a digital-analog converter, information inputs (memory) are connected to the output of the intermediate memory block (BPP), and the control inputs - with the corresponding outputs of the distributor connected with its input the output of the synchronization unit; the input of the intermediate memory unit is connected to the output of the descrambler, the input of which, together with the input of the synchronization unit, is connected to the input of the receiving device I. The disadvantage annogo device is its relatively low noise immunity, since the information used for transmitting the code Heminga, allowing the detect failures of one or two characters in the reference code, and failures of three, four and so on. d. not detectable symbols. In another known device of the telemetering system, failures are detected, then the device is closest in technical essence to the one proposed. It contains an intermediate memory block (PDU), a digital-to-analog converter (D / A converter), an address decoder, a storage device (memory), AND schemes, keys, an indicator, for example, an electron beam tube (CRT), a subtraction unit, a comparison circuit and a low-pass filter LPF) The BPP input is connected to the device input, the first BPP output is connected to the CRT brightness control input, the second to the input of the first DAC, and the third to the inputs of another DAC and address decryptor. The outputs of the latter are connected to the control inputs of the corresponding keys and the first inputs of the corresponding AND circuits, the outputs of which are connected to the control inputs of the corresponding memory. The memory inputs are combined and connected to the output of the first DAC and to one of the inputs of the subtraction unit, and the outputs are connected to the inputs of the corresponding keys, the outputs of which are combined and

connected to the second input of the subtraction unit and to the input of the vertical deflection of the CRT beam; the input of the horizontal deflection of the CRT is connected to the output of the second DAC. The output of the subtraction unit is connected to one of the inputs of the comparison circuit and to the input of the low-pass filter, the output of which is connected to the second input of the comparison circuit, the output of the latter connects the second inputs of the I circuits. The outputs of the device are the outputs of the charger and the CRT screen. In each channel of the device, the received reading is compared with the previously received one and is accepted (or not accepted) if it differs from it by an amount that is smaller (larger) than the generated 2 installation.

A disadvantage of this device is its relatively low accuracy due to the lack of static processing to combat interference.

The purpose of the invention is to increase its accuracy.

The goal is achieved by the fact that the receiving device of the telemetering system containing an intermediate memory block, the first input of which is connected to the information input of the device, the second input to the synchronizing input of the device, the information outputs of the intermediate memory block are connected to the corresponding information inputs of the keys of the first group, the key outputs are combined and connected to the first input of the subtraction unit and the first information output of the device, the control inputs of the keys are connected to the corresponding the outputs of the first decoder, the inputs of which are combined with the corresponding inputs of the digital-to-analog converter, the output of which is connected to the first input of the indicator, are entered into the second group of keys, the second decoder, pulse counter, code comparison unit, clock generator and functional converter, output of the number of samples of the intermediate memory block ti is connected to the first input of the code comparison unit, the output of which is connected to the second input of the indicator, the first control input of the device is connected to the first input of A clock pulse generator, the second input of which is combined with the third input of the intermediate memory block and connected to the second control input of the device, the output of the clock generator is connected to the first input of the pulse counter, the second and third inputs of which are connected to the third and fourth inputs of the device, respectively. the outputs of the pulse counter of the connector with the corresponding combined second inputs of the code comparison unit and the inputs of the first decoder, the second outputs of the pulse counter of the connection Inen with the corresponding combined third inputs of the unit of comparison and the inputs of the second

the encoder, the outputs of which are connected to the control inputs of the corresponding keys of the second group, the information inputs of which are connected to the corresponding information outputs of the intermediate memory block, the outputs of the keys of the second group are combined and connected to the second information output of the device and the second input of the subtractor whose output through the functional the converter is connected to the third input of the indicator.

Thanks to this in the proposed mouth. Static processing is carried out at multiple measurements of the telemetry parameter, and the estimated estimate is close to the optimal a posteriori maximum probability.

The drawing shows the structural block scheme of the proposed device.

Telemeter Receiver

The p system contains an intermediate memory block 1 (BPP), keys 2 of the first key group, keys 3 of the second key group, subtraction block 4, pulse counter 5, decryption blocks b and 7, block 8 of code comparison, indicator 9, for example, a cathode ray tube (CRT ), functional converter 10, digital-to-analog converter 11 (D / A converter), generator of 12 clock pulses (information 13 and synchronizing 14 inputs, information outputs 15 and 16 of the device, inputs 17, 18, 19 and 20 of the device are given in the drawing).

An intermediate memory block (NFP) for N samples is used for storing and connecting to the corresponding output of samples of a telemetry parameter, the second input of BNP 1 receives a clock with each new count, the number of which (n) is counted and stored in BNP 1. Except information exits, in PPP 1 there is an output of the number of samples (n) stored at a given time; when a logical signal is received, "1 to the second input of the generator 12 (" Start) "the code of the number (n) is set equal to one. PPP 1 can be completed on the basis of storage elements in the integrated design (analog or digital and simplest logic). Counter 5 with a capacity of N states is used to count the number of pulses at the input and has the first (for r lower bits) and second (for r high bits) outputs (for a binary counter r log2, 1). Counter 5 has control inputs 19, and 20 for setting codes on the first and second outputs. The counter 5 can be made on the basis of the counters in the integrated design, produced by industry. The code comparison block 8 serves to compare the codes at its inputs and output the luminance blocking signal of the CRT 9, if

The following conditions:, or Pg.n, or pn - the numbers corresponding to the codes at the inputs of the decoder 7 and 6 most-significant and lower-order bits, respectively. Comparison unit 8 may be made on the basis of logic elements.

The indicator 9 serves to present the input information to the consumer. The indicator 9 can be made on the basis of various information display devices, for example, on a CRT, matrix EL or LED indicators.

The functional converter 10 implements the function y / 2 / where Z is the input signal, or any other function with monotone conversion, for example, exp (- / Z /). The Converter 10 may be made on the basis of analog or digital integrated circuits. If the indicator 9 has a finite number of states (LEDs), then the converter 10 may consist of a set of comparators. The remaining units of the device are typical.

Receiver telemetering system works as follows.

At the first input of PPP 1, there are readings X of some telemetry parameter, which are stored in BPP I. With repeated parameter measurements, in the case of normal operation of the entire telemetering system, all stored counts differ from each other by a small fraction consisting, for example, of the error quantization and small fluctuation noise at repeated parameter measurements. But the system may be disturbed (malfunctioning), for example, malfunction due to interference in the communication channel. The downed samples differ sharply from the actual value and from each other, since they are caused by random impulse noise. Each sample stored in PPP 1 is compared by iterating with all other samples, due to the fact that the control inputs of keys 2 of the first group work N times less often than keys 3 of the second group, since they are controlled by the decoders 7 and 6 of the senior and junior counter bits 5, respectively. To make a final decision, it is not necessary to use the maximum possible number of N samples, the analysis is conducted as Xi samples arrive, but in order not to disrupt the synchronous operation of keys 2 and 3, counter 5, decoders 6 and 7, comparison unit 8 disables the CRT 9, if n, n, or or n- (P2, i.e., only the results of processing the actual recorded n samples in the remaining (Nh) memory cells are presented to the consumer, PPP 1 can be any information. Input To the vertical deviation of the CRT 9 signals Yii / Xj.-X ;, il, come from converter 10 2, ... n;

, 2, .... n, characterizing the degree of counts Xj to each other. Obviously, the smallest distance (Xj.-Xv) will be for the Xi values corresponding to the maximum probability density of the value, where X is the true value of the telemetry parameter, is the error of telemetry without static processing. The first input (horizontal deviation input) of the CRT 9 receives a signal corresponding to the reference number, 2, ... h, i.e., each vertical reading on the CRT screen 9 is allocated a corresponding vertical right. On each straight line the points are highlighted, their deviations from the zero level correspond to the values YiV-The operator, observing the screen of the CRT B, identifies the direct one on which the points are grouped and have the highest level (the level exceeds half of the maximum permissible error of the device). After the operator sees such a picture, he sends a signal “Stop, you take the number of this direct on the screen, dials this number on the third inputs of counter 5, after which the corresponding key 2 of the first group is triggered, and this count goes to the first information output 15. In addition, a second information output 16 is provided in the device, where you can output a count close in magnitude to 1 count to the count on the first output, its number is set at the second input of the counter 5. Then these counts can be further processed s, for example, by averaging, in order to further reduce the effects of small fluktatsionnyh interference. Note that with rare faults in the system, it is often enough to make decisions of two or three samples, since they are all close to each other if there is no impulse noise.

Thus, in the proposed device, an approximate analysis of the density of the received samples is carried out and the decision is made after the number of measurements, when the operator becomes clear which of these samples corresponds to the maximum probability density. For non-Gaussian interference (in particular, a relatively rare, but large amplitude of impulse noise in the measuring primary transducer or in the communication line), the proposed device allows to almost completely eliminate the influence of impulse noise, as well as reduce the RMS times the root mean square error due to low fluctuation noise with a close to normal distribution law.

Claims (2)

1. B. A. Kornilov and others. Multichannel code-impulse telemechanical device MKT-2, - “Instruments and control systems, 1972, No. II, p. 9. 2. USSR author's certificate No. 714457, cl. G 08 C 19/28, 1977 (prototype). G5