SU879797A2 - Noise suppressing device - Google Patents

Description

(54) DEVICE OF PROTECTION FROM. HITTER

I

The invention is adapted to radio engineering and can be used in radio engineering devices for various purposes in processing and extracting impulse signals from noise and noise on the screen of a cathode ray tube. Along the axis, author. St. No. 68QI88, an anti-interference device is known, comprising a serially connected converter, a code-voltage and a comparison unit, and a control unit and a quantizer in time between the output of the quantized L1I in time connected to the output of the comparison unit and the input of the converter -voltage includes serially connected first switch, adder, random access memory unit and second switch 15, and between the output of the control unit and the address input of the operative remembering unit are connected in series non-frequency dividers and an address driver, with the control inputs of the code-voltage converter, auto- w; switch, adder and driver Adrias are connected to the corresponding outputs of the control unit, with this

the External Outputs input is the second inputs of both switches and the setup input of a frequency divider, the second inlet of which is connected to the read input of the operational storage unit and the first to the control input of the first switch, the second input of the adder is connected to the output of the second switch, ttj;

However, in the known device, in the presence of a usable sigial, the number of pulses produced at the output of the device is protected from interference, in comparison with the number of pulses corresponding to the permissible value of horizontal alarms, which leads to an increase in the threshold and in the final count.

The purpose of the invention is to improve the noise immunity.

For this purpose, in the anti-interference device, which contains a series of code-voltage transducer and a comparator unit, as well as a control unit and a time quantizer, between the output of kwH | The user in time, connected to the output of the control unit, and the input of the code-voltage converter, connect the serially connected first switch, adder, random access memory and second switch, and serially connected frequency divider between the output of the control unit and the address input of the random access memory. and an address driver, where the control inputs of the code-voltage converters of the second switch, the adder and the address driver are connected to the corresponding outputs of the In this case, the input "External constants are volts; the second inputs of both switches and the installation input of a frequency divider, the second output of which is connected to the read input of the operational storage unit, and the first - with the control input of the first switch, and the second input of the adder is connected to the output of the second switch, the quantizer in time is connected to the output of the comparison unit through a serially connected selector for duration. and the element is NOT and the element is AND, the other input of which is connected to the corresponding output ohm control unit, between the output of the comparison unit and the other input of the time quantizer included in the delay element, the other inputs of the delay element and the selector duration connected to the input "External constant. The drawing shows a structural electrical circuit of the proposed device. The anti-interference device comprises a code-voltage converter 1, a comparison unit 2, a control block 3, a quantizer 4 in time, a first switch 5, an operational storage unit b, a second switch 7, a frequency divider 8, an address driver 9, an adder 10, the selector 11 for duration, the element is NOT 12, the element And 13 and the element 14 delay. The device works as follows. Before starting operation, the input External constants are entered: a predetermined threshold. Of block 2 comparison (only for the first line of the image to be expanded, and then a computational threshold of an operational storage unit 6 is entered into it), through the second switch 7 and the converter 1, the specified divider split ratio 8 is the frequency for the entire frame (determining the length of the sections into which all the lines of the television scan are divided). and the constant of false alarms in the adder 10 through the first switch 5, as well as the parameters (apejHH reaction of selector I, duration of selectable pulses, pulse repetition rate, pulse duration, etc., necessary to control the operation of selector P in duration and element 14. At that the time delay of the passage of pulses in element 14 must be equal to the time response of the selector P in duration, which for a period of time equal to the duration of the selectable pulse turns off the quantizer 4 in time and thereby excludes the selection of the selectable (useful) pulse per process calculates the threshold in the adder 10. The process of calculating the threshold for any P-section of any K-line is as follows: When the pulse starts, the frame or the start of the line, the control unit 3 generates a series of pulses, necessary for scanning each of the lines of the frame to be expanded. After passing each (p-1) burst of pulses from the output of control unit 3 (a burst of pulses is conventionally broken up into a burst of pulses, which facilitates the description of the operation of the device) at the divider output 8, a pulse is generated that rewrites the calculated threshold for (n-1) the K-line section from adder 10 to the operational storage unit 6 at (n-1) address formed in the address generator 9 (the calculated threshold value (for -1) of the K-line section will be used in the future only when scanning (l-1) of the section (K-b1) of the line). Then the frequency divider 8 is set to the initial state, thereby forming the next p-address in the address shaper 9, at which the threshold calculated on the p-segment (K, -1) of the line that enters the input is selected from the on-line memory block b /. block 2 through the second switch 7 and converter 1. This ensures that the output of the selector 11 for the n-section of the K-line forms a number of false alarms corresponding to the set value with a slight deviation from its nominal value. Simultaneously, the operation mode-subtraction is set in the adder 10 by supplying the appropriate control signal from the control unit 3. At this, the threshold code calculated on the p-section (K-1) of the line from the output of the second switch 7 is fed to one input of the adder 10 and to other inputs - the code of the permissible number of false alarms from the input "external constants through the first switch 5, which is subtracted from the plo code calculated on the n-section (K-I) of the line, and then the result is stored in the adder 10. Next, the receipt of the next p- "p The pulses to the inputs of the quan- tumor 4 in time and the frequency divider 8 in the adder 10 establish an operation mode — addition by supplying the appropriate control signal from block 3. At the same time, the output of the quantizer 4 is connected in time through the first switch 5 to the input of the adder 10 supplying the corresponding control signal from the output of the frequency divider 8 with its disconnection at the time of the existence of a selectable pulse, which eliminates the influence

Claims (1)

Claim Anti-jamming device on Aug. St. No. 680188, characterized in that, in order to increase the noise immunity, the quantizer is connected in time to the output of the block, compared through a series-connected selector in duration, the element and the element. And, the other input of which is connected to the corresponding output of the control unit, between the output of the comparison unit and the other input of the quantizer, a delay element is switched on in time, the other inputs of the delay element and the selector are connected to the “External constants” input.