SU1540031A1 - Device for reception of multiple-frequency signals - Google Patents

Abstract

The invention relates to communication technology. The purpose of the invention is to expand the ensemble of received multi-frequency signals. The device contains a mixer 1, a local oscillator 2, a storage unit (VC) 6 of a signal copy, a signal symbol detection unit (BO) 7 and a signal processing branch, each of which consists of a bandpass filter 3, a detector 4 and a threshold unit 5. The goal is achieved by introducing threshold blocks 5, BC 6 and BO 7, with which the output of the device produces signals indicating that the received multi-frequency signal is detected or is not matched with this device. Given il. perform BH 6 and BO 7. 4 Il.

Description

The invention relates to communication technology and can be used in the construction of receivers of multi-frequency signals in asynchronous address communication systems.

The purpose of the invention is to expand the ensemble of received multi-frequency signals.

Figure 1 shows the structural electrical circuit of the device; Fig. 2 is a structural electrical circuit of a signal copy storage unit; FIG. 3 shows a structural electrical circuit of a signal symbol detection unit; 4 shows timing diagrams for the operation of the device.

The device contains a mixer 1, a local oscillator 2, bandpass filters 3, detectors 4, threshold blocks 5, block 6 for storing a copy of a signal, block 7 for determining a signal symbol.

The signal copy storage unit 6 is formed by an M-input circuit OR 8, a distributor 9 pulses per M channels, a register 10, two-input circuits AND I1, an M-input circuit OR 12.

The signal symbol determining unit 7 contains an encoder .; 13, subtractive device 14, block 15 versus zero, two-input circuit OR 16, counters 17 and 18, two-input circuit AND 19 with inverse input and two-input circuit OR 20o

A device for receiving multi-frequency signals operates as follows.

The signal arriving at the input of the mixer 1, after transferring its spectrum to the intermediate frequency, enters the input of the bandpass filters 3, which divide the DC signal into M elementary signals. Elementary signals are sent to the detectors 4. The voltage

(L

with

O1 4b

WITH

taken from the outputs of the detectors 4 (fig. 2a-d) is compared with a predetermined threshold in the threshold block 5. The threshold block, when exceeded, generates a pulse (FIG. 4e, k), which through the OR circuit 8 of block 6 (fig.2l ) arrives at the clock input of the pulse distributor 9. The pulse distributor 9, depending on the JQ order of the pulses, polls the corresponding cells of register 10, and when the first pulse arrives, the first register 10- is polled (a pulse of 5 down appears at the output of the first channel itel) when the second pulse arrives, the second cell, etc. Content

register 10 cells after polling through a device for receiving multi-frequency circuits AND 11 and OR 12 are fed to the input of 2Q signals, containing a sequence that indicates that a multi-frequency signal is received that is not consistent with this device. In this case, the counter 17 provides for bringing the device to the initial state (it zeroes the counters 17 and 18 and returns the initial distributor 9 pulses to the initial state).

The structure of the received code sequence is pre-recorded in register 10 from the ROM by clicking on one of L (L is the number of signals in the communication system) of the control buttons.

In the subtracting device 14. A binary code is supplied to the input A of this device in binary code, taken from the outputs of the encoder 13,

The difference between the numbers A and B from the output of the device 14, in the presence of a resolution signal supplied from the element 8 of the block 6, is fed to the input of the block 15. Comparison with zero. In that case, when

The connected local oscillator and the mixer, the second input of which is the device input, and the M signal processing branches, consisting of series-connected bandpass filter and detector, are characterized in that, in order to expand the ensemble of received multi-frequency signals, serially connected

neither

which indicates that a multi-frequency signal is received that is not consistent with this device. In this case, the counter 17 provides for bringing the device to the initial state (it zeroes the counters 17 and 18 and returns the initial distributor 9 pulses to the initial state).

The structure of the received code sequence is pre-recorded in register 10 from the ROM by pressing one of the L (L is the number of signals in the communication system) control buttons.

Claims (1)

Invention Formula The connected local oscillator and the mixer, the second input of which is the device input, and the M signal processing branches, consisting of series-connected bandpass filter and detector, are characterized in that, in order to expand the ensemble of received multi-frequency signals, serially connected the difference between the numbers A and B is zero, the block of the signal copy storage unit and the block 35 The 1 5 produces a pulse signal, which is recorded by the counters 17 and 18. If the difference is not equal to zero, the result of the comparison is registered only by the counter 17. In the case when the structure of the received signal and the copy of this signal coincide, counter 18 registers zero differences, and a signal appears at the output of this counter, which indicates that the received multi-frequency signal is detected. Otherwise, counter 18 does not work, which leads to the appearance of a signal at the output of the circuit And 19, 40 determining the signal symbol, the first and second outputs of which are the outputs of the device, and in each signal processing branch a threshold unit, the mixer output is connected to the bandpass filters, detector outputs are connected to the inputs of the corresponding threshold blocks, the outputs of which are connected to the corresponding inputs the signal symbol determining unit and the signal copy storage unit, and the third output of the signal signal determination unit is connected to the synonization input of the signal copy storage unit. signal copy storage unit and block determining the signal symbol, the first and second outputs of which are the device outputs, and the threshold block in each signal processing branch, the mixer output is connected to the bandpass filter inputs, the detector outputs are connected to the inputs of the corresponding threshold blocks, the outputs of which are connected to the corresponding inputs of the symbol definition block the signal and the signal copy storage unit, and the third output of the signal symbol detection unit is connected to the synchronization input of the signal copy storage unit. From 6loko 6 From ale. 17 N Qmnpecejk X torus N Od U1 -P-oh oj To block 7 Schi, gz not