CN101303408B

CN101303408B - Method for extending azimuth scanning data for generating radar PPI image and circuit thereof

Info

Publication number: CN101303408B
Application number: CN2008100665103A
Authority: CN
Inventors: 王立真; 付郁
Original assignee: EWARE INFORMATION TECHNOLOGY Co Ltd
Current assignee: EWARE INFORMATION TECHNOLOGY Co Ltd
Priority date: 2008-04-03
Filing date: 2008-04-03
Publication date: 2012-06-27
Anticipated expiration: 2028-04-03
Also published as: CN101303408A

Abstract

A method of azimuth scan data for generating radar PPI images in an expanding way and a circuit thereof are disclosed, wherein, the method comprises the steps: taking a pulse signal PR emitted by a radar as trigger to produce a synchronized control signal, by virtue of alternate control storing the echo data E(Thetam, Ri) of a radar emitting pulse PRm in sequence in a memory cell with the addressD(Thetam, Ri) in a first echo data memory and writing the echo data E(Thetam-1, Ri) in a second echo data memory in a mapped memory with the address D(Thetaj, Ri); and before the reach of a following pulse signal PRm+1, repeatedly reading and writing the echo data E(Thetam-1, Ri) in the second echo data memory in sequence to each distance unit (D(Thetaj+1, Ri) D(Thetaj+2, Ri)... D(Thetaj+n, Ri) in the next position neighboring Thetaj in the mapped memory. The method of the invention causes the radar echo data to keep continuous in position, reforms the display of the radar PPI images, can be applicable to radars with various antenna scanning cycles and probing cycles.

Description

Expansion generates the method and the circuit of the azimuth scan data of radar PPI images

Technical field

The present invention relates to kind of a radar PPI images treatment technology, when especially relating to a kind of display device that utilizes the raster scanning system and realizing that radar PPI images shows, the extended method and the circuit of azimuth scan data when its radar PPI images generates.

Background technology

In direct beam display, the planimetric position of radar shows that (Plan Position Indicator, PPI) image just disappears after sweep trace skims over owing to do not repeat to show automatically, only stays the twilight sunset of very short time, thereby observed echo is difficult.And raster scanning shows that the scope display of system is the reflection that the pixel data of radar PPI images is formed the PPI image in mapped memory; Form output with raster scanning shows then; And repeat to show with the frequency of per second tens He Zhi; So just can on screen, see stable radar PPI images, improve observation efficiency greatly.

After the resolution of raster display is confirmed; The pixel count that the grid of grating is corresponding is also just confirmed thereupon; And the grating grid number on its circumference should be 3.14 times (horizontal resolution=vertical resolutions of PPI picture usually) of horizontal resolution or vertical resolution; For the display of 1024 * 1014 resolution, the grid number on its circumference is: 3.14 * 1024 ≈ 3215; Consider the registration bias when polar coordinates convert rectangular coordinate to; Also should be multiplied by a coefficient=

like this; In the radar antenna ring is swept the time (being called a radar antenna cycle again) in a week; Above even scanning that

must be arranged is inferior just can make the pixel on each grid obtain upgrading.

And when raster display was operated in the 2:1 extended mode, the pixel on the sweep radius expanded to 1024, and then the grid on the circumference is approximately: 3.14 * 1024 * 2.5=6430; Satisfy even scanning times continuous on the orientation and should be 6430 *

then in the radar antenna ring is swept the time in a week; Should write scan-data equably 9093 times, could guarantee that all pixels all obtain upgrading.

But; Because the rotation and the transponder pulse of radar antenna are nonsynchronous; Be difficult to satisfy at a radar antenna 4547 or 9093 detect cycles were just in time arranged in the cycle; When the detect cycle number of an antenna in the cycle during, can be updated because of scanning with regard to some pixel less than above-mentioned numerical value; Even the condition above having satisfied also can be missed some unit because antenna rotates inhomogeneous or unstable, if having echo information or clutter information to exist, just will be retained in for a long time on the screen in the unit that is not scanned, form and disturb bright spot.

Therefore; How to solve the pixel matching between the fixing mapped memory of less radar polar coordinates azimuth scan echo data and fine-resolution meshes; Radar PPI images to avoid exporting raster scan display to through mapped memory occurs discontinuous or the division phenomenon, has become one of technical barrier of current urgent need solution.

Summary of the invention

The present invention proposes a kind of method and circuit of expanding the azimuth scan data that generate radar PPI images; When utilizing the display device of raster scanning system to realize that radar PPI images shows with solution; Exist the azimuth scan echo data not enough owing to the radar detection number of cycles is less relatively, cause to such an extent that the radar PPI image is discontinuous or the technical matters of division occurs on the orientation.

For solving technical matters of the present invention, the present invention discloses a kind of method of expanding the azimuth scan data that generate radar PPI images, comprising:

With radar transmitted pulse signal P _RFor triggering, produce synchronous control signal, control in an alternating manner radar transmitted pulse P _RmEcho data E (θ _m, R _i) order is saved to wherein that the address is D (θ in the first echo data storer _m, R _i) storage unit, and with the echo data E (θ in the second echo data storer _M-1, R _i) write in the mapped memory and D (θ _j, R _i) the corresponding a series of storage unit of azran in; And in continuous next radar transmitted pulse signal P _Rm+1Before the arrival, repeat to read that the address is D (θ in the second echo data storer _j, R _i) storage unit in preserve echo data E ( _M-1, R _i) and write successively in the mapped memory and θ _jEach storage unit D (θ on adjacent next orientation to be updated _J+1, R _i), D (θ _J+2, R _i) ..., D (θ _J+n, R _i).

More excellent, shown in synchronous control signal be to utilize with pulse signal P _RAs the trigger pip of frequency divider, by frequency divider at each pulse signal P _RAlternately the output signal of upset is controlled two echo data storeies down.

More excellent, the echo data E (θ of the said write first echo data storer or the second echo data storer _m, R _i) address D (θ _m, R _i), and from the first echo data storer or the second echo data storer, read echo data E (θ _M-1, R _i) address D (θ _j, R _i), all be to be that the first echo data storer and the second echo data storer carry out addressing and select the input data through address selector.

In addition, the present invention discloses a kind of circuit of expanding the azimuth scan data that generate radar PPI images, comprising:

Frequency divider is used for radar transmitted pulse signal P under each radar antenna orientation _RFor triggering, produce synchronous control signal;

First, second echo data storer of working in an alternating manner is used for the control according to synchronous control signal, when with radar transmitted pulse P _RmEcho data E (θ _m, R _i) order is saved to that the address is D (θ in the first echo data storer _m, R _i) storage unit the time, and with D (θ _j, R _i) address is D (θ in the second echo data storer for read the address _j, R _i) storage unit in the echo data E (θ that preserves _M-1, R _i);

The echo data outlet selector is used for the control according to synchronous control signal, selects to read the echo data E (θ in the first echo data storer or the second echo data storer _M-1, R _i) and export that coordinate address is D (θ in the mapped memory to _j, R _i) a series of memory cells, and in continuous next radar transmitted pulse signal P _Rm+1Before the arrival, control repeats to read the echo data E (θ in the first echo data storer or the second echo data storer _M-1, R _i) and export D (θ in the mapped memory to _j, R _i) storage unit D (θ on adjacent next orientation to be updated _J+1, R _i), D (θ _J+2, R _i) ..., D (θ _J+n, R _i).

More excellent; The circuit that expansion of the present invention generates the azimuth scan data of radar PPI images also comprises: first, second address selector that is connected with first, second echo data storer respectively is respectively applied for to first, second echo data storer carries out addressing and imports data with selection.

More excellent, the circuit that expansion of the present invention generates the azimuth scan data of radar PPI images also comprises: be used for the meet at right angles coordinate transformation circuit of coordinate address of polar coordinates address translation, its bind image storer.

Compared with prior art, the present invention has following beneficial effect:

The present invention is through existing azimuth scan echo data is expanded on the orientation; Solved the problem of the fixing mapped storage pixel coupling of less radar polar coordinates azimuth scan echo data and fine-resolution meshes well; The radar PPI images of having avoided exporting raster scan display to through mapped memory occurs discontinuous or the division phenomenon; Make that radar return keeps having improved the demonstration of radar PPI images continuously on the orientation.In addition, the present invention is all applicable for the radar of various antenna scanning cycle and detect cycle.

Description of drawings

Fig. 1 is the coordinate conversion principle schematic;

Fig. 2 is the synoptic diagram of a preferred embodiment of the present invention.

Embodiment

For ease of understanding, simply the radar PPI images generation technique is made brief account earlier:

Present display device with grating sweep volume system; Like CRT monitor, LCD display and PDP display; It is when realizing that radar PPI images shows; All want elder generation the azimuth-range coordinate of the echo data of radar transmitted pulse, be positioned in a series of storage unit of a mapped memory according to its place; Be applicable to the mapped memory of raster scanning system, its storage unit is come addressing with rectangular coordinate system X-Y, a pixel on the corresponding display screen of each storage unit.

As shown in Figure 1, with range coordinate R _iWith azimuthal coordinates θ _jExpression radar target position, and raster display adopts the rectangular coordinate system X-Y of screen display, if represent the target location with rectangular coordinate system X-Y, it is following that then polar coordinates convert the fundamental relation of rectangular coordinate to:

X _i＝X _c+R _i·Cosθ _j；

Y _i＝Y _c+R _i·Sinθ _j。

I is a range unit number in the formula, i _MaxBe generally 1023, represent that promptly the maximum operating range R with radar is a radius, will be apart from being divided into 1024 unit; So R _iRepresent the current detecting location and the distance of radar; J is an orientation quantifying unit number, j _MaxBe generally 4096, be i.e. when expression is rotated with 360 ° when radar antenna, be divided into 4096 unit with 360 °, so orientation θ _jOrientation angles when the expression radar antenna is surveyed current location.

If (X _c, Y _c) when being the true origin of rectangular coordinate system X-Y, the image of i range unit in the radar return data, the location in the PPI mapped memory, available computes:

X _i＝R _i·Cosθ _j；

Y _i＝R _i·Sinθ _j；

Wherein, i=0,1,2 ..., max (the common value of max is 1023); J=0,1,2 ..., max (the common value of max is 4095).

Radar antenna is positioned at orientation θ _mTransponder pulse (or scanning impulse) signal P _Rm, receive orientation θ _mThe time detecting location and radar antenna distance be respectively R ₀, R ₁..., R _MaxThe echo data E (θ of each detecting location _m, R _i) (wherein, i be 0,1 ..., max), be called here and accomplish orientation θ _mUnder a range sweep, in range sweep process each time, with echo data E (θ _m, R _i) order is saved to the echo data storer; Then, with echo data E (θ _m, R _i) polar coordinates change into and θ _m, R _iCorresponding a series of X, Y coordinate address data X _{(j, i)}-y _{(j, i)}The mapped memory of raster scanning system comes addressing with rectangular coordinate system X-Y, and its memory address is X _{(j, i)}-y _{(j, i)}Storage unit in memory contents be corresponding echo data E (θ _m, R _i), and the displaying contents of a pixel on the corresponding display screen of the memory contents in each storage unit.

Please refer to shown in Figure 2ly, the circuit that the present invention is used to expand the azimuth scan data that generate radar PPI images mainly comprises: with radar transmitted pulse signal P _RmThe frequency divider 10 of Shi Zuowei synchronous control signal, first, second address selector 21 and 22, first, second

echo data storer

31 and 32 and echo data outlet selector 40.

Wherein, first, second

echo data storer

31 and 32 is according to radar transmitted pulse signal P _RControl mutual alternation: at radar transmitted pulse signal P _RmThe time, suppose frequency divider 10 wherein an output terminal is effective the time, first address selector 21 is selected and pulse signal P _RSynchronous address D (θ _m, R _i), this address D (θ _m, R _i) be transponder pulse at detecting location R _iThe time echo data E (θ _m, R _i) polar coordinates, and with transponder pulse P _RmAll echo data E (θ in the range sweep process _m, R _i) order is saved to that the address is D (θ in the first echo data storer 31 _m, R _i) storage unit in; Second address selector 22 is the corresponding polar coordinates address D (θ of current renewal pixel in the selection mapped memory 50 then _j, R _i), be D (θ by echo data selector switch 40 address from the second echo data storer 32 _j, R _i) storage unit in the echo data E (θ of reading and saving _M-1, R _i), and with echo data E (θ _M-1, R _i) write that coordinate address is D (θ in the mapped memory 50 _j, R _i) a series of storage unit in.

When radar sends transponder pulse signal P _Rm+1, at this moment, frequency divider 10 overturns, and control is with transponder pulse P _Rm+1Echo data E (θ _M+1, R _i) write that the address is D (θ in the second echo data storer 32 _m, R _i) storage unit in; First address selector 21 is current renewal pixel corresponding address D (θ in the selection mapped memory 50 then _j, R _i), by the echo data E (θ of echo data selector switch 40 reading and saving from the first echo data storer 31 _m, R _i), and with echo data E (θ _m, R _i) write in the mapped memory 50 address corresponding polar coordinates address D (θ _J+n, R _i) storage unit in.

Wherein, i value successively is 0,1,2 ..., max (the common value of max is 1023); J value successively is 0,1,2 ..., max (the common value of max is 4095, and n is the broadening ratio, such as, n ≈ 8192/m).

Because mapped memory 50 reads echo data E (θ through echo data outlet selector 40 with fixing cycle and speed from the first echo data storer 31 or the second echo data storer 32 _M-1, R _i), faster than echo data input operation usually, and and P _RAsynchronous.Be that mapped memory 50 is with radar transmitted pulse P _RmThe echo data of a range sweep from the first echo data storer 31 or the second echo data storer 32, read finish after, next transponder pulse signal P _Rm+1Do not arrive yet, then mapped memory 50 repeats to read echo data E (θ through echo data outlet selector 40 from the first echo data storer 31 or the second echo data storer 32 _M-1, R _i), thereby the PPI mapped storage that continues next orientation upgrades realization scan-data broadening.

Therefore; The present invention considers that the display of raster scanning system carries out pixel with fixed rate and upgrades; Sweep in the cycle at the radar antenna ring; Radar scanning how many times no matter, when not receiving the echo data of single pass on certain radar antenna orientation, the echo data that just repeats to read on this radar antenna orientation of receiving last time upgrades the corresponding pixel of radar PPI images.If display always upgrades by 8192 sweep traces, then the present invention is equivalent to scanning exhibition data number of times has been extended to 8192 times.So being equivalent to sweep in the cycle display that the azimuth scan data have been extended to grid scanning system at a radar antenna ring, the present invention upgrades the required number of times of pixel.

Claims

1. a method of expanding the azimuth scan data that generate radar PPI images is characterized in that, comprising:

With radar transmitted pulse signal P _RFor triggering, produce synchronous control signal, control in an alternating manner radar transmitted pulse P _RmEcho data E (θ _m, R _i) order is saved to wherein that the address is D (θ in the first echo data storer _m, R _i) storage unit, and with the echo data E (θ in the second echo data storer _M-1, R _i) write in the mapped memory and D (θ _j, R _i) a series of storage unit that polar coordinates are corresponding, and in next radar transmitted pulse signal P _Rm+1Before the arrival, repeat to read that the address is D (θ in the second echo data storer _j, R _i) storage unit in the echo data E (θ that preserves _M-1, R _i), and write successively in the mapped memory and coordinate address D (θ _j, R _i) coordinate address D (θ on adjacent next orientation to be updated, corresponding stored unit _J+1, R _i), D (θ _J+2, R _i) ..., D (θ _J+n, R _i) corresponding a series of storage unit;

Wherein, D (θ _m, R _i) be the real-time polar coordinates of radar emission direct impulse echo; M is the sequence number that antenna loop is swept radar transmitted pulse in the week; D (θ _j, R _i) press the coordinate that fixed rate upgrades the PPI mapped memory for the PPI image generation system;

Wherein subfix i is that range unit number, subfix j are that orientation quantifying unit number, subfix n are the broadening ratio.

2. expansion according to claim 1 generates the method for the azimuth scan data of radar PPI images, it is characterized in that, said synchronous control signal is to utilize pulse signal P _RAs the trigger pip of frequency divider, by frequency divider at each pulse signal P _RAlternately the output signal of upset is controlled two echo data storeies down.

3. expansion according to claim 1 generates the method for the azimuth scan data of radar PPI images, it is characterized in that the echo data E (θ of the said write first echo data storer or the second echo data storer _m, R _i) address D (θ _m, R _i), and from the first echo data storer or the second echo data storer, read echo data E (θ _M-1, R _i) address D (θ _j, R _i), all be to be that the first echo data storer or the second echo data storer carry out addressing through the address date selector switch.

4. a circuit of expanding the azimuth scan data that generate radar PPI images is characterized in that, comprising:

First, second echo data storer of working in an alternating manner is used for the control according to synchronous control signal, when with radar transmitted pulse P _RmEcho data E (θ _m, R _i) order is saved to that the address is D (θ in the first echo data storer _m, R _i) storage unit the time, the address is D (θ in the second echo data storer and read _j, R _i) storage unit in the echo data E (θ that preserves _M-1, R _i);

The echo data outlet selector is used for the control according to synchronous control signal, selects to read the echo data E (θ in the first echo data storer or the second echo data storer _M-1, R _i) and export that coordinate address is D (θ in the mapped memory to _j, R _i) a series of memory cells, and in continuous next radar transmitted pulse signal P _Rm+1Before the arrival, control repeats to read the echo data E (θ in the first echo data storer or the second echo data storer _M-1, R _i), and export in the mapped memory and coordinate address D (θ _j, R _i) on adjacent next orientation to be updated, corresponding stored unit and coordinate address be D (θ _J+1, R _i), D (θ _J+2, R _i) ..., D (θ _J+n, R _i) a series of storage unit;

5. expansion according to claim 4 generates the circuit of the azimuth scan data of radar PPI images, it is characterized in that, also comprises:

First, second address selector that is connected with first, second echo data storer respectively is respectively applied for first, second echo data storer is carried out addressing.

6. expansion according to claim 4 generates the circuit of the azimuth scan data of radar PPI images, it is characterized in that, also comprises:

Be used for the meet at right angles coordinate transformation circuit of coordinate address of polar coordinates address translation, its bind image storer.