SU650089A1 - Apparatus for transmitting and receving frequency information - Google Patents

Description

one

The invention relates to the transmission of discrete information and can be used to transmit discrete messages over communication channels from information sources to an electronic computer, as well as to transmit information to the lower levels of automated production control systems.

A multi-frequency device for transmitting discrete messages is known, which contains an information source, modulators, transmitters on the receiving side of the receiver, a decoder and filters 1.

The disadvantages of the known device are low information transfer rates and noise immunity.

PT is also known a device for receiving messages through several channels, comprising a detector, an information source, an amplifier, a synchronizing device, priority detection schemes for message channels with constant-time adjustment of the transmitter 2.

The disadvantages of the known device are low information transfer rate, since reception is performed over one information channel, which has priority over others, and low noise immunity, because there is no information feedback in the device that

leads to the disappearance of the information package, the reception of information is not on the agreed filters. The closest to the technical essence of this invention is a device for transmitting and receiving frequency information, containing on the transmitting side serially connected receiver of acknowledgment signals, a block of repeated symbols received in error, an information source, a modulator and an amplifier connected to one end of the receiver. of the communication channel, the receiver input of the handshake signals is connected to one end of the reverse communication channel; on the receiving side, information channels containing serially connected filters and an amplifier, the receiver whose output is connected to the threshold element, the output of the threshold element of each information channel is connected to the corresponding input of the decoder, the output of which is connected to the first input of the OR element directly and through the serially connected output register, error detection unit and transmitter to the other end of the return channel This connection, the output of the block for detecting the change of the information signal through the memory element is connected to the first

the input of the noise pickup pulse generator, the output of which is connected to the control inputs of the receivers of the information channels, the filter inputs of which are connected to the other end of the direct communication channel 3.

The disadvantages of the known device include low noise immunity when the useful signal freezes in the forward link. In this case, false registration of information occurs, since the voltage remains at the receivers and when the signal arrives from the forward link, the voltage at the terminals will not increase from the zero level.

In a feedback system, the combinations of transmitted information are repeated, which are false, thus increasing the time for transmitting information.

The aim of the invention is to improve the speed and noise immunity of the device.

This goal is achieved by the fact that a demodulator detected in the communication channel and a demodulator in each information channel, the input of which is connected to the amplifier output, is output to the receiver input and to the corresponding input of the information change detection unit; the signal, the output of the OR element is connected to the second input of the noise compresser pulse generator, the second input of the OR element is connected to the output of the signal interruption detection unit in the communication channel, the input of which is connected to the other end of the direct channel la communication. In addition, the interrupt detection unit in the communication channel contains a series-connected detector and a threshold element, the output of which is connected to the output of the interruption detection unit of the communication channel, whose input is connected to the detector input.

FIG. 1 shows a block diagram of the proposed device; in fig. 2 is a block diagram of a communication channel interrupt detection unit; in fig. 3 is a time diagram of the operation of the device in conjunction with a communication channel interruption detection unit.

The proposed device for transmitting and receiving frequency information contains on the transmitter side receiver 1 of the queuing signals, unit 2 of repeated symbols received in error, source 3 and ;; formation, modulator 4, amplifier 5, forward link 6, at the receiver filters 7 and 8, inverters 9 and 10, demodulators 11 and 12, receivers 13 and 14 frequency signals, threshold elements 15 and 16, decoder 17, element OR 18, output register 19, error distribution block 20, transmitters 21, reverse communication channel 22, block 23 of information signal change detection, m memory 24, the compensation pulse generator 25 and the noise signal detecting unit 26 interrupts a communication channel (Fig. 1).

The interrupt detection unit 26 in the communication channel consists of a detector with an amplifier 27 and a threshold element 28 (Fig. 2).

The device works as follows.

Claims (3)

10 The transmitted signal from information source 3 (Fig. 1) is fed to modulator 4, where it is transformed into a form corresponding to a given communication channel, amplified by amplifier 5 and supplied to forward channel 15 of connection 6. At the receiving side, the dual-frequency sources are separated by filters 7 and 8. Each filter 7 and 8 selects one of the frequencies of its group to which it is tuned, and does not let the frequency of the neighboring group pass, 20 which results in single-frequency signals from the corresponding group at the output of the filters. These signals are amplified and normalized by the amplitude of amplifiers (limiters) 9 and 10 and fed to the 5 inputs of demodulators 11 and 12. Signals amplified and normalized in amplitude in demodulators 11 and 12 are separated from the noise generated by the forward channel. connection 6. Each demodulator consists of two channels: a channel that does not change the phase of the signal and noise, and a channel that changes the phase of the signal and sound by 180 ° and produces suppression of the positive signal. On the summing element, the addition of these two 5 channels occurs, as a result of which no noise is present in the signal at the output of the demodulator. The signals from demodulators 11 and 12 are fed to the inputs of receivers 13 and 14 of frequency signals, which are made 0 of narrowband switched filters matched with the received signals. Signals are extracted by frequency signal receivers, detected by detectors with threshold elements 15 and 16, and after 5 triggering of threshold elements are decoded by decoder 17. From the output of decoder 17, combinations of square pulses in binary code are recorded, which are entered into the output register 19. from the output of the element OR 18, an impulse is removed corresponding to the moment of fixing the next parcel by the receiver circuit. This pulse enters the shaper 25 pulse compensation 5 noise. The latter begins to produce a quench pulse, which is fed to the control inputs of the receivers 13 and 14 of the frequency signals. Since an irreducible alternate-sending code is used to transmit information in this device, when changing packages at the input of a receiver, frequencies are changed in at least one of the groups of operating frequencies. This changes the signal level at the output of one of the converters included in block 23, which, after rectifying and fixing the voltage level, depending on the frequency at the input of the receiver, will turn off the damping pulse from the control inputs of the receivers 13 and 14 of the frequency signals. At the same time, the signal from the irry communication channel 6 is fed to the input of the signal interruption detection unit 26 in the communication channel. This signal, after passing through the amplifier and the detector 27 (Fig. 2), is converted into a constant voltage necessary for triggering the threshold element 28, which generates a pulse of interruption of the communication channel. If there is a useful signal at the receiver input, the signal interruption detection unit in the communication channel will not affect the operation of the receiver. During interruptions in the communication channel, the threshold element 28 (Fig. 2) is triggered and at the output of the signal interruption detection unit 26 in the communication channel there is a pulse, which through the OR 18 element and the driver 25 of the interference compensation pulses arrive at the control inputs of the receivers 13 and 14 frequency signals, while the receivers will be absorbed. Receivers of frequency signals 13, 14 will be recharged until a useful signal arrives at the input of the receiver. When a useful signal arrives at the receiver input, the interrupt signal detecting unit 26 in the communication channel through the OR element 18 and the driver 25 of the interference compensation pulse will disconnect the dither pulse from the control inputs of the receivers 13 and 14 of the frequency signals. Receivers 13 and 14 will receive frequency information from the zero level, when receiving frequency information from a non-zero level, the symbols will be distorted, which in turn will lead to an increase in reseps on the reverse link. FIG. 3 shows a timing diagram of the operation of the device in conjunction with a communication channel interrupt detection unit. In the timing diagram (Fig. 3), the following symbols are given: t / Bx is the input signal; U, U is the voltage at the outputs of the first and second frequency signal receivers; f / nc is the signal at the output of the communication channel interrupt detection unit; t / r is the signal at the output of the interference cancellation pulse generator. At the expense of the signal detection unit in the communication channel and its inclusion in the receiver circuitry, the information transfer rate by multi-frequency asynchronous devices increased by 8-10%, the noise immunity of the device increased twice as compared with the prototype. The simplicity of the construction of an interrupt signal detection unit in a communication channel allows it to be implemented in industrial enterprises producing multi-frequencies 5 10 15 20 25 30 35 40 45 50 55 60 65 devices for transmitting discrete information without disrupting the process and carrying out additional work. Claim 1. Device for transmitting and receiving frequency information, containing on the transmitting side serially connected receiver of acknowledgment signals, block of repeated symbols received with error, information source, modulator and amplifier connected to one end of a direct communication channel, input the receiver of the acknowledgment signals is connected to one end of the reverse communication channel, on the receiving side information channels containing serially connected filter and amplifier, a receiver whose output is connected to The orog element, the output of the threshold element of each information channel is connected to the corresponding input of the decimator, the output of which is connected to the first input of the OR element directly and through serially connected output register, error detection unit and transmitter to the other end of the reverse link channel, output of the information changer the signal through the memory element is connected to the first input of the noise compensation pulse generator, the output of which is connected to the control inputs of information receivers Ion channels whose filter inputs are connected to the other end of a direct communication channel, characterized in that, in order to improve the speed and noise immunity of the device, a signal interruption detection unit in the communication channel and each information channel are inserted into it and the demodulator connected to the output of the amplifier, output to the receiver input and to the corresponding input of the information signal change detection unit, the output of the OR element is connected to the second input of the noise compensation pulse generator, the second input of the element This OR is connected to the output of the signal interruption detection unit in the communication channel, the input of which is connected to the end of the direct communication channel. 2. The device according to claim 1, characterized in that the interrupt detection unit of the signals in the communication channel comprises a detector connected in series and a threshold element, the output of which is connected to the output of the interruption detection unit of the communication channel, the input of which is connected to the input of the detector. Sources of information taken into account in the examination 1. USSR author's certificate jVo 366489, cl. G 08C 19/28, 08.02.71, 7 2. UK Patent No. Cl. H 3Q, 03.17.75. 1406901, 3. USSR author's certificate 650089 8 No. 516084, cl. G 08 C 19/12, 21.03.75.