SU680016A1 - Remote measuring multichannel device - Google Patents

Description

one

The invention relates to telemechanics and may be used to create telemetry systems with frequency multiplexing of communication channels and estimate the measured parameters by the code combination of transmitted messages.

Telemetry systems are known that in each channel contain a sensor with a digital output, channel-forming equipment / a on the receiving side (connected to the transmitting side of the communication channel) —filters with subsequent detection and averaging of their signals l.

The disadvantage of such telemetry systems is low noise immunity when exposed to strong interference, especially in the signal frequency band.

The closest to the technical essence of this invention is a device for multichannel telemetry, containing on the transmitting side in each channel a sensor, the input of which is connected to the input of the device, and the output through the converter is connected to the input of the generator, the outputs of the generators are connected to the corresponding inputs of the first matching unit, the output of which through the communication line is connected at the receiving side to the input of the second matching unit, each output of which is connected to the first inputs of the corresponding sy synchronous detectors, the output of the corresponding generator is connected to the second input of each synchronous detector, the output

0 of each synchronous detector is connected to the input of the low-pass filter, and the output block f2.

A disadvantage of this device is the low noise immunity of the received signals.

The aim of the invention is to improve the noise immunity of signal reception,

The goal is achieved

Claims (2)

0 by the fact that, in the proposed device, on the receiving side in each channel introduced are a rectifier No. 1, averaging filters, an inverter, a second synchronous detector, a low frequency filter, a generator and an adder, in each channel the first input of the second synchronous detector is connected to the corresponding output The second matching unit, the output of the second generator, is connected to the second input of the second synchronous detector, the output of which is connected via a second low-pass filter connected in series, a second rectifier, a second averaging filter, and The inverter is connected to the first input of the adder, the output of the first low-pass filter is connected through the first rectifier and the first averaging filter connected in series to the second adder, the output of which is connected to the input of the output unit. FIG. 1 shows the circuit diagram of the device in FIG. 2 is a diagram of his work. The device contains sensors 1 transducers, generators, the first matching unit 4, the second matching unit 5, synchronous detectors and b {-6 / ,, low-frequency filters, rectifiers, 8,; - 8, average filters, , inverter 10-10 ,, output blocks, generators, In matora 13. The device works as follows. The square-wave voltage from the sensor is converted into a sawtooth (see Fig. 2), which, in turn, is converted into a radio pulse with a variable frequency within f -) - f2. On the receiving side (in each channel) in the signal band are the frequency bands of the two synonic filters uf and controlled by the reference oscillators fon.i ol.1 and the frequency differs from the frequency fpn-- a value slightly larger if. Thus, when the signal frequency changes from f- (to fg, the outputs of both synchronous filters produce voltage pulses sequentially during (Fig. These voltages are further corrected with in blocks 8 and are averaged by filters 9 and then the second subchannel of synchronous detection 6-9; f the signal is inverted by block 10, and summed with the signal of synchronous detection of subchannel 6-9. At the output of the adder 13 a signal voltage appears (Fig. 2g) and is applied to the output block 11. When exposed to fluctuation noise at the outputs of both synchronous f Litrov beating voltages occur, which are rectified and averaged by the above-mentioned blocks. These voltages act on the input of the adder throughout the lifetime of the beats and are subtracted, which causes interference suppression in the signal band. Since synchronous filters have a very narrow the bandwidth (in units of hertz), the difference between f and f.-2 may be small, which causes narrowband channels.With a small value of the band uf (several hertz), the interference in the signal band is correlated (but not with the signal) and effectively. The latter distinguishes the proposed telemetry system from the known ones. The remaining n receiver channels are similar, i.e. each receiver channel is divided into two subchannels, the signals of which are subtracted from one another in the manner described above. Thus, in the proposed device, fluctuation disturbances in the signal band are suppressed. Apparatus of the Invention A device for multichannel telemetry, comprising, on the transmitting side in each channel, a sensor whose input is connected to the device input, and an output through a serially connected converter and generator is connected to the corresponding input of the first matching unit, whose output the input of the second matching unit, the outputs of which are connected in each channel to the first input of the first synchronous detector, to the second input of which the output of the gene is connected RATOR, the output of the first synchronous detector is connected to the input of the first low-frequency filter, and the output unit, characterized in that, in order to improve the noise immunity of the device, rectifiers, averaging filters, an inverter, and the second synchronous detector, low frequency filter, generator and adder, in each channel the first input of the second synchronous detector is connected to the corresponding output of the second matching unit, the output of the second generator is connected to the second input of the second sync a second detector, a second rectifier, a second averaging filter, and an inverter are connected to the first cyMiviaTopa input, the output of the first low frequency filter is connected through a first rectifier, and the first averaging filter is connected to the second input of the adder, the output of which is connected to the input of the output unit. Informadiya sources taken into account during the examination 1. A. Manovtsev Introduction to digital telemetry, M., 1S67. 2. USSR author's certificate fM 11485, cl. G08 19/12, 1974. L j: .. v A , „, 1 p - I, ™ -, 4ibtl-iiJl Q-s-Hir-Te lj "H3-i3-S P-Fi- {- {1 .Jfi ™ I --- L-- Sr {343-a4ij --- i, qpgn%  j, ..- rp -,.-.-. -yt-- h n r rt G 4 h - EJ: U ; 31 s -V L1  t 7, J / 7f 4r / j,