SU1764182A1 - Device for radiolocation information visualizing on raster indicating television-type screen - Google Patents

Description

one

(21) 4779691/09 (22) 01.01.90 (46) 09/23/92. Bul No. 35

(71) All-Union Scientific Research Institute of Radio Equipment

(72) V.N.Abrosimov, V.A.Levitsky and L.G.Ortenberg

(56) U.S. Patent No. 4,412,220, cl. G01 S7 / 44, 1983.

(54) DEVICE FOR DISPLAYING RADIOLOCATION INFORMATION ON A SCREEN OF A RASTER TELEVISION TYPE INDICATOR

(57) The invention relates to a technique for displaying information and can be used to obtain a bright, flicker-free image of the raw analog radar information on a television-type raster display screen. The purpose of the invention

is a reduction in hardware by eliminating a storage unit for storing information about the afterglow function. The device for displaying radar information on a television type raster display screen contains a video signal amplitude converter 1 into a code, a luminance code register 2, a buffer register 3, a raster memory control unit 4, raster memory block 5, digital-to-tax converter 6, raster indicator 7, converter of polar coordinates to rectangular 8, address counter 9, counting trigger 10, blocks b spherical memory 11 and 12, a comparison unit 13. The purpose of the invention is achieved by eliminating a memory node for storing information about the afterglow with the simultaneous introduction of two small volume buffer memory, an address counter, a counting trigger and a comparison block. 1 il.

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The invention relates to the field of information display technology and can be used to obtain a strong flicker-free image of the raw analog radar information on a television-type raster display screen.

The purpose of the invention is to reduce the amount of equipment by eliminating a storage unit for storing information about the afterglow function.

The drawing shows a block diagram of the proposed device for displaying radar information on a television-type television screen.

A device for displaying radar information on a screen of a television type raster indicator contains a video signal amplitude 1 converter into a code, a brightness code register 2, a buffer register 3, a raster memory control unit 4, a raster memory block 5, a digital-to-analog converter 6, a raster indicator 7, a converter polar coordinates to rectangular 8, address counter 9, counting trigger 10, buffer memory blocks 11, 12, and comparison block 13.

A device for displaying radar information on a screen of a television type raster indicator works as follows.

Angular position signals of the radar antenna in the form of North and azimuthal pulses, as well as range pulses, are fed to the inputs of the polar coordinate converter to rectangular 8, and the real-time conversion is carried out from the polar coordinate system to the rectangular coordinate system.

At the same time, the analog video signal of the radar is fed to the transducer 1 of the amplitude of the video signal into a code, also operating in real time. The digital code of the amplitude of the video signal is fed to the input of the register 2 of the luminance code, in which the total luminance code is formed, containing: the amplitude code of the video signal, the sign of luminance attenuation and

given attenuation law code.,.

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The luminance attenuation attribute determines the need for luminance attenuation. The formation of it is discussed in detail later in the text. The attenuation law code determines how the luminance should be attenuated: linearly, logarithmically, or another law.

Information about the rectangular coordinates (X, Y) of each point of the radar image together about the total luminance code is recorded in the buffer

register 3, from which the clock signals from the raster memory control unit 4 are read. In this case, the coordinate information (X, Y) is fed to the raster memory block 5 and is selected

corresponding raster memory element. The total luminance code goes to the raster memory control unit 4, and the luminance code stored in the selected element of the raster memory unit arrives here.

In the control unit 4 of the raster memory, this luminance code is modified in accordance with the values of the attenuation characteristic and the damping law code,

comparing the modified luminance code with the newly received luminance code and then writing the larger of the compared values to the currently selected element of the raster memory block 5.

Thus, the afterglow duration for each raster element depends on the luminance code stored in this element of the raster memory block, and the incoming total luminance code.

The luminance codes read from the raster memory block 5 are converted to analog form in a digital-to-analog converter 6. The television signal generated in it (video signal and sync pulses) is then fed to the raster indicator 7.

Let us consider in more detail the formation of the sign of attenuation of brightness. In the process of converting polar coordinates to rectangular, some points of the radar image fall into the same raster element.

The following cases are possible where the radar image points fall into the same element of the raster memory block:

1) the point corresponding to the given range discrete at the current angular scan, and the point corresponding to the previous range discrete on the current angular scan;

2) the point corresponding to the given range discrete on the current angular scan, and the point corresponding to the same range discrete on the previous angular scan;

3) the points corresponding to the given distance sampling on the current angular scan, and the points corresponding to the same

discrete range on subsequent angular sweeps.

The luminance attenuation sign must be formed for all points of the radar image, except for the points that fall in the same element of the raster memory block. For each next point, it is necessary to establish whether the coordinates of this point have changed with respect to the coordinates of previously displayed neighboring points, i.e. analyze the cases named in clauses 1 and 2. Changing the coordinates of the analyzed points is determined by the values of the lower digits of the coordinates X and Y. The logic circuit of block 15 of comparison 13 implements the algorithm:

PZ - (Xn.K © Xn-1.K) - (Yn ,, K) t (Xn, K® Xn, K-l) :( Yn.K © Yn, K-t), (1),

where PZ is a sign of attenuation of brightness;

Хр.к - the youngest bit of the code of the coordinate 20 X of the point n and the range discretes on the K angular scan;

Xn-1, k - the least significant bit of the code of the X coordinate of the point (n - 1) range increments on the K angular sweep; 25

Xn, k-1 is the least significant bit of the code of the X coordinate of the point n, the range discretes on the (K - 1) angular sweep.

Similar designations are used for the lower order of the Y coordinate. 30.

To memorize the low-order bits of the X and Y coordinate codes of the radar image points corresponding to one angular sweep, two blocks of buffer memory 35 11 and 12 are used, each of which alternately records the low-order bits of the coordinate codes of the next angular sweep point, while the codes of the coordinates of the previous angular 40 sweep Xn, k-1 are read from the other; Yn, K-i. Addresses for writing to the blocks of the buffer memory are generated by an address counter 9, to the input of which range impulses (AD) are received.

The counting trigger 10, to the input of which 45 azimuth pulses arrive, provides with signals at its 2 outputs variable-mode control write-read of the blocks of the buffer memory — 11 and 12. From their outputs, the signals go to the input of the comparison unit 13, the other inputs of which receive a control signal (CI) from the counting trigger 10, codes of coordinates of the current points Xn, k; Yn, K from the output 55 of the converter of polar coordinates to rectangular 8, codes of coordinates of the previous points Xn-1, k; Yn-i, K from the output of the buffer register 3. Comparison unit 13 carries out, according to a signal, a counting trigger 10, the choice for analyzing the coordinates in turn from blocks

buffer memory 11 or 12 and implements the algorithm described by formula (1).

Thus, at the output of the comparator unit 13, a luminance attenuation sign is generated for each point of the image of the radar information. At the same time, the attenuation of the image brightness is provided sequentially, point by point, simultaneously with the movement of the radar sweep, and during one time period of the radar's review, the image brightness is attenuated over the entire area of the screen of the television-type raster indicator.

The amount of memory of the memory node to be deleted for storing information from the afterglow function Q is determined by the expression

QnK, (2)

where n is the number of elements of the raster horizontally, i.e. in one line of the raster;

K - the number of lines of the raster.

For a square TV raster n K and Q n2, For modern high definition television systems n K 1000-2000 elements. Accordingly, Q is 10 -4 to 10-bit. To implement such a memory capacity on modern domestic large integrated circuits - LSIs require about 62-248 LSIs, which with modern module design will be about 2-8 constructive modules.

The blocks of the buffer memory 11, 12 of the proposed device are the operational memory, each of which must have a SI capacity:

, (3)

where the coefficient 2 is determined by the need to memorize the lower order bits of the coordinates in X and Y, the value of n is similar to that given in expression (2).

Accordingly, in the numerical expression, Qt is 2 10 -3 103 bits,

To implement such a memory, one LSI is sufficient. The address counter 9, the trigger trigger 10, the comparison unit 13 of the proposed device requires for the implementation of several (less than 10) integrated circuits of average integration.

Thus, the exclusion of a storage unit for storing information about the afterglow function significantly reduces the amount of apparatus equipment for displaying radar information on a television-type raster display screen.

Claims (1)

Invention Formula A device for displaying radar information on a television-type raster display screen, containing a polar coordinate transducer to rectangular, the three inputs of which are, respectively, the signals of the signals of the North, azimuth and range pulses, the converter of the amplitude of the video signal into the code, the input of which is the input of the analog video signal, the luminance code register, the first input of which connected to the output of the amplitude converter of the video signal to the code, the second input is designed to supply a damping code, a buffer register, the first input of which is connected to the first output of the converter polar coordinates are rectangular, the second input is with the output of the luminance code register, the raster memory control unit, the first input of which is connected to the first output of the buffer register, and the first output is connected to the third input of the buffer register, the raster memory unit, the first the input of which is connected to the second output of the buffer register, the second input to the second output of the raster memory control unit, the first output of the raster memory block is connected to the second input of the raster memory control unit, the second output is connected to the digital input a tax converter, the output of which is connected to the input of a raster indicator, characterized in that, in order to simplify by excluding a memory node for storing information about the afterglow function, two blocks of buffer memory, an address counter, a counting trigger and a comparison unit, and the counter input are entered the address is connected to the input of the range pulses, the input of the counting trigger is connected to the input of the azimuthal pulses, the address inputs of each of the two blocks of the buffer memory are connected to the output of the address counter, the control input corresponds to The opposite phase output of the counting trigger, and the information inputs of each of the two buffer memory blocks are connected to the output of the polar coordinate converter to the rectangular ones, the first and second inputs of the comparator block are connected respectively to the outputs of the two buffer memory blocks, the first control input is connected to one of the the outputs of the counting trigger, the information input — with the output of the polarizer to rectangular coordinates, and the second control input — with the third output of the buffer register, the output of the comparison unit is connected to tert they code register input luminance