JPS6323511B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention utilizes a three-dimensional/polar coordinate readout method for a storage device, particularly a three-dimensional memory in which storage planes constituting a two-dimensional plane are arranged in the height direction, to enable radar observation. 3 above in a form that corresponds to the radar antenna pattern to simulate
3 of storage devices that access dimensional memory
This relates to dimensional/polar coordinate readout methods.

Although the present invention is not limited thereto, for example, in a radar echo simulator,
The flow of aluminum particles dispersed in the air is simulated and displayed on a display screen. The group of aluminum pieces mentioned above is generally called a chaff, and is used to deceive the presence of an aircraft.
Information corresponding to the flow of such channels is stored on the memory plane, and the information is stored in the radar antenna.
In order to read and display data in a form corresponding to a pattern, it is necessary to arrange memory planes constituting a two-dimensional plane in the height direction, and to access these memory planes according to polar coordinates. Furthermore, it is necessary to determine which storage plane in the height direction to select according to the antenna pattern.

The present invention aims to solve the above-mentioned problems, and has a pattern memory for selecting the above-mentioned storage plane in the height direction as a function of the distance from the radar site stored in, for example, a ROM. The purpose of this invention is to enable readout in accordance with the antenna pattern of the antenna. Therefore, the three-dimensional/polar coordinate readout method of the storage device of the present invention has a storage plane that constitutes a two-dimensional plane, and a readout system based on a specified azimuthal direction centered on one point on the two-dimensional plane. In a polar coordinate reading method of a storage device, the content of the coordinate position on the storage plane is read by extending the distance by a unit distance, and then the azimuth direction is shifted to perform reading by extending the distance. , a plurality of the storage planes are configured to be arranged in a height direction, and a distance counter for counting the unit distance, and a function of the output of the distance counter are used to store which storage plane to select from among the plurality of storage planes. and a height direction access circuit section having at least a pattern memory for decoding and a decoder for decoding the output of the pattern memory. The present invention is characterized in that a selected storage plane among the plurality of storage planes is selected in an accessible manner. This will be explained below with reference to the drawings.

1A, B, and C are explanatory diagrams explaining the principle of reading out a storage plane constituting a two-dimensional plane according to polar coordinates; FIG. 2 is an explanatory diagram illustrating the concept of a storage device used in the present invention; FIG. 3 is an explanatory diagram illustrating a readout mode when the antenna pattern is not taken into consideration, FIG. An example of an antenna pattern having a cosecant square characteristic, FIG. 6 shows the configuration of an example of the present invention, FIG. 7 is an explanatory diagram of an antenna pattern having a pencil beam shape, and FIG. A modification of the configuration shown in FIG. 6 when the antenna pattern shown in FIG. 7 is used is shown.

In FIG. 1A, 1 represents the X-Y plane storage plane, A represents the radar site point, 2 represents the chaff (or its flow pattern), B represents the chaff scattering point, and 3 represents the radar observation limit area.

If you want to simulate a state in which chaffs flow as shown in the diagram 2 when chaffs are scattered at point B, information "1" is stored at the coordinate position of the chaff existence point in the diagram on one memory plane 1, and 1 as polar coordinates. That is, while the azimuth angle of the radar is at angle θ, points a ₁ , a ₂ , a ₃ . . .
The storage contents corresponding to each coordinate position are read out by sequentially extending the distance r as shown in the coordinate position of Information "1" is read out and displayed from the coordinate position (x, y) corresponding to the location where "2" exists.

In this case, since the coordinate positions on the memory plane 1 must take discrete values, when reading the above points a ₁ , a ₂ . . . under a certain azimuth angle θ, the following It is done like this. That is, when the azimuth angle θ is given, the value of cos θ and the value of sin θ can be expressed as ROM
As shown in FIG. 1B, coordinate positions X and Y are obtained as a function of the distance r according to Y= _r 〓 ^r=0 cos θ X _r 〓 ^r=0 sin θ }(1). but,
As for the actual access address, overflow of the added value in equation (1) above is monitored, and the cumulative value of the overflow is used as the Y address and the X address. Figure 1B shows the azimuth angle θ=
FIG. 1C shows the access points on the storage plane 1 as a function of the distance r. Needless to say, when accessing polar coordinates, under the azimuth θ,
As shown in the figure, the memory plane 1 is accessed, and then the azimuth is advanced to (θ+△θ), and the memory plane 1 is similarly read out with the distance r set to "0", "1", "2", etc. .

Polar coordinate access is performed as described above, but the flow of the chaff 2 changes over time, and it is necessary to sequentially change the storage pattern on one storage plane 1 in response to this. Since this point is not directly related to the present invention, a description thereof will be omitted.

The explanation related to FIG. 1 is about one storage plane, but when considering the flow in the height direction of the chaff 2, as shown in FIG. 2,
Storage planes 1-0, 1-1, ..., 1-n are arranged in the height Z direction, and each storage plane 1-0,
1-1, . . . , 1-n are read out all at once from the same coordinate position (x, y). When information "1" is read from any one storage plane, for example 1-i, a dot is displayed on the display screen corresponding to the distance r.

This state is equivalent to rotating the plane shown by diagonal lines 4 around the radar site points A and A' as shown in FIG.

FIG. 4 shows an explanatory diagram illustrating a readout mode according to an embodiment of the present invention in consideration of a radar antenna pattern. In the figure, symbol A is the radar
The site, r is the horizontal distance, Z is the height, is the antenna angle, and 5 is the antenna pattern.

Assuming that the antenna pattern has the characteristics of pattern 5 shown in the figure with the antenna fixed at an angle, when access is taken into consideration the antenna pattern, pattern 5 with point A as the center is used.
It is necessary to access within the range of the rotating body rotated in all azimuth directions. To this end, in one embodiment of the invention, access is made as follows.

That is, under a certain azimuth θ, points a ₁ , a ₂ , a _{3 .} . . are accessed by extending the distance r as explained with reference to FIG. Only storage plane 1-0 is accessible at illustrated distance r=0, and storage plane 1 is made accessible at distance r=a ₁ .
-1 and 1-2 are accessible, and the distance r
= a ₂ storage planes 1-2, 1-3 and 1-
Only 4 and 1-5 are accessible, and the distance r=
In a ₃ , only storage planes 1-3 to 1-8 are made accessible, and so on. Of course, when access is completed for a certain azimuth as described above, the azimuth is next shifted to (θ+Δθ) and access is made in the same manner.

The same is true when the radar is installed at a certain height H above the ground and the antenna pattern 5 has a cosecant square characteristic as shown in FIG. The storage plane to be accessed may be selected according to the

FIG. 6 shows the configuration of an embodiment of the present invention. The symbols 1-0, 1-1, ..., 1-n in the figure correspond to those in FIG. 2, 6 is a polar coordinate access circuit section, 7 is a height direction access circuit section, 8 is a storage device, and 9 is an azimuth angle. Counter, 10 is trigonometric function ROM, 11 is adder, 12
13 represents an X-direction address counter, and 13 represents a Y-direction address counter. Further, 14 represents a distance counter, 15 represents an antenna pattern ROM, and 16 represents a decoder. Furthermore, ARP is an azimuth reference pulse, which gives one pulse corresponding to the direction of the antenna, for example, the north direction.
ACP is an azimuth change pulse that gives 4096 pulses corresponding to 360° in synchronization with changes in the azimuth angle of the antenna, and TRIG is a radar trigger pulse that gives 4096 pulses in synchronization with changes in the azimuth angle of the antenna. , and the "distance clock" represents a pulse that provides a distance increment corresponding to the distance r.

The azimuth counter 9 is reset in response to the pulse ARP and counts the pulse ACP. Therefore, the output of the azimuth angle counter 9 represents the azimuth angle θ shown in FIG. 1A. Trigonometric function
The ROM 10 generates a sine value sin θ and a cosine value cos θ corresponding to the azimuth θ. The adder 11 converts the input values sin θ and cos θ into the (1)
Add according to the formula. When an overflow (OVF) occurs regarding Σsinθ, the contents of the counter 12 are incremented by 1. Further, when an overflow (OVF) occurs regarding Σcosθ, the contents of the counter 13 are incremented by 1. Therefore, under a certain azimuth θ, counters 12 and 13
As explained in connection with FIGS. 1B and 1C, the content of each of is a function of the distance r, and
The address information of the coordinate positions corresponding to the points a ₁ , a ₂ , a ₃ . . . shown in Figure A is stored in each storage plane 1-0 to 1-
Give for n.

Meanwhile, the distance counter 14 counts up the distance clock. antenna pattern ROM
15 stores which storage plane should be selected corresponding to the distance r so as to match the radar antenna pattern 5. That is, in the case of the antenna pattern 5 shown in FIG. 4, as explained with reference to _FIG . 1 to 1-2, storage planes 1-2 to 1-5 when distance r=a ₂ , storage planes 1-3 to 1-8 when distance r=a ₃ , etc. has been done. When the output of the distance counter 14 is, for example, r= _a2, the antenna pattern ROM 15 is stored in the memory plane 1-2 or 1.
Generates an output that selects -5. The decoder 16 is
Decode the output of antenna pattern ROM15,
Depending on the decoding result, a chip select signal is applied to the selected storage plane to make the storage plane accessible.

It is configured as described above, and under a certain azimuth θ and based on the distance clock, the coordinate positions corresponding to points a ₁ , a ₂ , a ₃ . . . as explained with reference to FIG. Each storage plane 1-0 to 1-n
provides access address information, while decoder 16 provides chip select for a given storage plane. As a result, for example, in the case of the antenna pattern 5 shown in FIG. 4, under a certain azimuth θ, the storage plane 1-0 is accessed corresponding to the distance r=0, and the read result is read data R-
given to a display device (not shown) as DATA,
Storage planes 1-1 and 1- correspond to distance r=a ₂
The results read from 2 and 2 are ORed and given to the display device, and so on. Then, when the readout that extends the distance r under the azimuth angle θ is completed, a pulse ACP is applied to increase the azimuth angle (θ+△θ).
A similar readout is then performed. In this case, when reading under a different antenna pattern, the antenna pattern ROM
It will be sufficient to replace 15.

In the above description, it is assumed that the characteristics of the radar antenna are selected in a desired shape (for example, as shown in FIG. 5) so that the space including the height direction can be searched.
However, recently, the antenna pattern is set in a so-called pencil beam shape as shown in FIG. 7, and a space is searched by changing the angle. FIG. 8 shows a modification of the configuration shown in FIG. 6 in this case. In addition, in the figure, only the height direction access circuit part 7 is shown for the sake of simplicity, and the other parts are the 6th direction access circuit part 7.
It can be considered that the configuration is exactly the same as that shown in the figure. Reference numerals 7, 14, 15, and 16 in the figure correspond to those in Fig. 6, and 17
represents the elevation counter. Elevation counter 17 measures the elevation of the antenna.
It counts elevation pulses given in response to changes in the depression angle, and the output of the counter 17 represents the angle. In this case, the antenna pattern ROM 15 includes a storage plane selected corresponding to pattern 5 shown in FIG. 7 when angle = ₁ , a storage plane selected when angle = ₂ , and a storage plane selected when angle = ₃ . Each distance r of the memory plane,...
You can think of it as remembering each time. Therefore, for a certain azimuthal angle θ, at a distance r=a ₁ and in synchronization with the elevation pulse, the angle ₁ ,
₂ , ₃ , etc., a predetermined storage plane is selected, and then the same process is performed under the distance r=a ₂ , and so on, when the access for the predetermined azimuth θ is completed. The azimuth angle is (θ+△
θ), and as the angle changes from ₁ to ₂ to ₃ , a predetermined storage plane is selected.

As explained above, according to the present invention, three
It is possible to access the dimensional storage in polar coordinate format. And antenna pattern ROM
By changing the contents of , access corresponding to any antenna pattern becomes possible. Also, if necessary, access corresponding to a search using a pencil beam becomes possible.

[Brief explanation of the drawing]

1A, B, and C are explanatory diagrams explaining the principle of reading out a storage plane constituting a two-dimensional plane according to polar coordinates; FIG. 2 is an explanatory diagram illustrating the concept of a storage device used in the present invention; FIG. 3 is an explanatory diagram illustrating a readout mode when the antenna pattern is not taken into consideration, FIG. An example of an antenna pattern having a cosecant square characteristic, FIG. 6 shows the configuration of an example of the present invention, FIG. 7 is an explanatory diagram of an antenna pattern having a pencil beam shape, and FIG. A modification of the configuration shown in FIG. 6 when the antenna pattern shown in FIG. 7 is used is shown. In the figure, 1-0, 1-1, ... are storage planes, 2 is a chaff (or its flow pattern), and 5 is a storage plane.
is an antenna pattern, 6 is a polar coordinate access circuit, 7 is a height direction access circuit, 8 is a storage device, 9 is an azimuth counter, and 10 is a trigonometric function.
11 is an adder, 12 and 13 are address counters, 14 is a distance counter, 15 is an antenna pattern ROM, 16 is a decoder, and 17 is an elevation counter.

Claims (1)

[Scope of Claims] 1. A memory plane forming a two-dimensional plane is provided, and the above-mentioned memory plane is extended by a unit distance in a specified azimuth direction with one point on the two-dimensional plane as the center. In a polar coordinate reading method of a storage device configured to read out the contents of a coordinate position on a storage plane, and then read out by shifting the azimuth direction to extend the distance, the storage plane is arranged in a plurality of locations in the height direction. A distance counter for counting the unit distance; a pattern memory for storing which storage plane to select from among the plurality of planes based on the output of the distance counter;
A vertical access circuit section having at least a decoder for decoding the output of the memory is provided, and during the reading over the extended distance, the output from the vertical access circuit section is used to read data in the plurality of storage planes. A three-dimensional/polar coordinate reading method for a storage device, characterized in that a selected storage plane is selected in an accessible manner. 2. The height direction access circuit section is provided with an elevation counter that specifies the elevation/depression angle, and is configured to select the pattern memory based on the output of the elevation counter, and the elevation counter 3. The storage device according to claim 1, wherein the pattern memory selected by the output of the distance counter is accessed as a function of the output of the distance counter.
Dimensional/polar coordinate readout method.