SU1001144A1 - Signal receiving device - Google Patents

Description

The invention relates to telemechanics and can be used in frequency asynchronous telemechanics systems.

A device for improving the noise immunity of receiving video radio pulses is known, comprising a low frequency filter and a threshold element connected to its output, the low frequency filter input being connected either to a communication line when video pulses are received, or to an amplitude detector or frequency discriminator output when radio pulses are received.

A disadvantage of this device is that it is effective only in the case when the duration of the interference is much shorter than the signal duration.

The closest to the proposed technical entity is a device for receiving signals, containing in each information channel a signal selector, the input of which is connected to the input of the device, and locking C2 D blocks.

The device eliminates the appearance of a false pulse at any of the exits, however, when exposed to interference, there is a loss of information.

since the telemechanic signals do not pass through the logical nodes, which reduces the noise immunity of the receiver. The purpose of the invention is to increase the reliability of the device.

This goal is achieved by the fact that a delay element and a low-frequency filter are entered into each information channel, except for the last, into a device for receiving signals, which contains a Xssd information channel, a signal selector, whose input is connected to the device input. an information channel is entered an element is NOT and in each information channel the logic block is executed on a trigger, elements AND and element Ш1Н, the output of the trigger is connected to the first input of the first element And, the outputs of the first and second elements And through the OR element connected to the input of the low-pass filter, in the information channel besides the last, the output of the signal selector is connected via the delay element in the logic unit with the first trigger inputs and the second element And, the output of the signal selector of the last information channel under: keys in the logical block; to the second

the inputs of the trigger and the first element il, the output of the element NOT of the last information channel is connected to the second input of the second element AND logical block of each information channel.

FIG. 1 shows a block diagram of the proposed device} in FIG. 2 time diagrams of his work.

The device includes selectors 1.1-1 (n + 1) signals, a NOT 2 element, 3.1-Zp delay elements and low-pass filters 4.1-4p, as well as 5.1-5p logic blocks, each of which contains trigger b, And 7 elements and 8 and the element OR 9. The number 10 denotes the input of the receiver, and the numbers 11.1-11p - its outputs.

FIG. 2, 12 is the undistorted, 13 is a distorted signal from the output of the selector 1.1} 14 is the distorted signal from the output of delay element 3.1, 15 is the interference signal from the output of the selector 1 (P-I), 16 is the signal at the direct output of the trigger 6 } 17 and 18 are the output signals of the And 7 and 8 elements, respectively, 19 is the signal at the output of the OR 9 element; 20 - signal at the output of the first information channel 11.1.

The device works as follows.

In the absence of interference at the output of the selector 1 (n + 1) there is a logical zero level, and at the output of the element iiE 2 - the level of the logical unit, as a result of which the element And 7 is open, and the element And 8 is closed. The signal from the output selector 1.1 through the delay element 3.1, the open element AND 7, the element OR 9 and the low-frequency filter 4.1 goes to the output of, for example, the first channel 11.1. When the pulse 10 interferes with the input of the receiver 10 at the output of the selector 1 (n + 1), a voltage pulse is written to the trigger b - the value of the undistorted signal at the moment before the noise arrives and the opening element I 8, and the inverted pulse of the noise from the output element NOT 2 closes the element AND 7 At the output of the channel 11.1 through the elements And 8, ISH 9 and the low-frequency filter 4.1, the signal comes from the trigger trigger 6.

The delay element 3.1 ensures the delay of the signal for the time required to write undistorted information to trigger b, taking into account the possible difference in the speed of selectors 1.1-1p and 1 (n + 1), i.e. the delay time of the delay element 3.1 required for the normal functioning of the receiver is much less than the duration of the information pulse. Thus, at the output of the element OR 9, during the action of the disturbance, there is an undistorted signal stored by trigger 6, however, after the end of the interference pulse, the opened element AND 7 passes the memorized distorted signal to the output of element OR 9 for delay 3.1. This phenomenon is eliminated by the low-frequency filter 4.1, the kosaly passes only those pulses, the duration of which is not less than

holding element 3.1 delay.

The proposed device provides reliable reception of information when exposed to interference 15.1 in the pause and the occurrence of a false pulse

at the output of the selector 1.1, when driving interference 15.2 during a pulse and suppressing (crushing) it, with distortion of the falling or leading edges of the information pulse interference 15.3

and 15.4 respectively, as well as in

the case of the arrival of interference 15.5, not causing distortion of information.

Claims (2)

1.Tutevich V.N. Telemechanics. M., energy, 1973, p. 114-115. 2. Patent Czechoslovakia D44240, cl. G, 08 C 15/02, published 1972 Dprototype). W {u S.n Y. .n H f | / a 1 / 7 je JTTL -TL. f & . J l