JP2000147113A - Synthetic aperture radar signal processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a synthetic aperture radar(SAR) signal processor in which a required memory capacity is small, in which a memory neck and a bus neck are not generated, and which can prevent the influence of a trouble from being expanded to the processor as a whole when the trouble is generated. SOLUTION: This signal processor is provided with a data division mechanism 11 by which observation data on an SAR are divided into a plurality of partial images, a plurality of data reproduction mechanisms 12 by which a compression processing operation in a range direction and an azimuth direction is performed with respect to the given partial images and which generate partial reproduction images with respect to the given partial images, and a data distribution mechanism 13 by which the plurality of partial images divided by the data division mechanism 11 are distributed to the proper data reproduction mechanisms 12. A plurality of partial images are processed in parallel by a plurality of data reproduction mechanisms 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a synthetic aperture radar (Synthe) mounted on an artificial satellite or an aircraft.
tic Aperture Radar, SAR
SAR for digitally processing the image data obtained by the above method and reproducing an image that can be understood by humans.
The present invention relates to a signal processing device.

[0002]

2. Description of the Related Art In the field of remote sensing using artificial satellites or aircraft, SAR is well known as a sensor capable of observing the surface of the earth with high resolution without being affected by weather conditions such as clouds. I have. As shown in FIG. 16, imaging data (hereinafter referred to as observation data) captured by the SAR is n in the range direction and m in the azimuth direction.
Since it cannot be understood by humans as it is, a process for reproducing an image that can be understood by humans (hereinafter, referred to as a reproduced image) (hereinafter, referred to as an image reproducing process) is required.

FIG. 17 is a flowchart showing the flow of a basic SAR image reproducing process. Image reproduction processing in SAR compresses observation data in the range direction (hereinafter, referred to as SAR compression).
Then, compression is performed in the azimuth direction (hereinafter, referred to as azimuth compression) to generate a reproduced image. When this image reproduction processing is performed by digital processing, the range compression and azimuth compression processing are performed by convolution of point image pattern data for each line of observation data. However, if the convolution process is executed as it is, it takes an enormous amount of processing time.
FT), complex multiplication, fast inverse Fourier transform (hereinafter, referred to as FT)
IFFT) is generally used to increase the speed.

In order to improve the quality of a reproduced image, processing such as range migration correction is indispensable. The range migration correction is for correcting blur caused by a change in the distance (range) between the SAR and the imaging target, and examples thereof include range coverage correction and range walk correction. In this range coverage correction, after performing FFT processing in the frequency space in the middle of compression in the azimuth direction,
As shown in FIG. 18, the same range data distributed on the quadratic curve is resampled (interpolated and picked up) on a straight line.

Hereinafter, a conventional SAR signal processing apparatus for performing such SAR image reproduction processing will be described. FIG. 19 is a block diagram showing a configuration of a conventional SAR signal processing device described in, for example, Japanese Patent Application Laid-Open No. 2-243987. In the figure, reference numeral 1 denotes a plurality (N) of range compression processors for performing range compression of observation data, 2 denotes a plurality of (M) azimuth compression processors which also perform azimuth compression, and 3 denotes each of the range compression processors 1 and This is a data transfer path for transferring processing data between the azimuth compression processors 2.

Next, the operation will be described. Here, in the conventional SAR signal processing device shown in FIG. 19, the observation data is divided into N in the azimuth direction, and the range compression is processed in parallel by N range compression processors 1, and then the range compression is performed. Is divided into M in the range direction, and azimuth compression is processed in parallel by M azimuth compression processors 2.

The observation data is composed of n data in the range direction and m data in the azimuth direction as shown in FIG. Such observation data is divided into N pieces in the azimuth direction as shown in FIG. 20, and these are input to the N range compression processors 1 respectively. That is, each range compression processor 1 has n in the range direction.
And (m / N) data in the azimuth direction.

Each range compression processor 1 has its (n ×
When (m / N)) data is input, 1
Line data, that is, n data, is extracted and range compression processing is performed. In the range compression process, FFT, complex multiplication, and IFFT processes are performed on the n pieces of data extracted in this manner, as shown in FIG. By repeating this (m / N) times, range compression is performed on all of the input observation data.

Next, each range compression processor 1 transfers the data after range compression to each of the M azimuth compression processors 2 via the data transfer path 3.
At this time, the data is transferred so as to be divided into M in the range direction as shown in FIG. That is, each azimuth compression processor 2 receives (n / M) data in the range direction and m data in the azimuth direction.

When each of the azimuth compression processors 2 receives the ((n / M) × m) data, it extracts one line of data in the azimuth direction, that is, m data, and performs azimuth compression processing. I do. In the azimuth compression processing, the FFT, range migration correction, complex multiplication, and IFFT processing are performed on the m pieces of data thus extracted, as shown in FIG. By repeating this (n / M) times, azimuth compression is performed on all the input range-compressed data.

However, the range-compressed data is divided into M in the range direction, and the M azimuth compression processors 2
When azimuth compression is performed in parallel, range migration correction processing poses a major problem as described below.

Here, a description will be given of a range coverage correction, which is one of the range migration corrections, as an example. Range cover correction is performed in the azimuth direction as described above.
After processing T, the same range data distributed on the quadratic curve is resampled on a straight line (see FIG. 18). The data is, as shown in FIG. Will be present across
A method for solving this problem is described in, for example, Japanese Patent Application Laid-Open No. 58-1919.
No. 79, for example.

FIG. 23 shows, for example, the above-mentioned Japanese Patent Application Laid-Open No. 58-19 / 1983.
FIG. 1 is a block diagram illustrating an example of a configuration of a conventional SAR signal processing device described in Japanese Patent Application Publication No. 1979. In the figure,
Reference numeral 2 denotes an azimuth compression processor for performing azimuth compression processing equivalent to that shown in FIG. 19, and reference numeral 4 denotes an FFT which is configured to be accessible from all azimuth compression processors 2 and processed by each azimuth compression processor 2. This is a shared memory for storing subsequent data.

Next, the operation will be described. Here, in the conventional SAR signal processing device shown in FIG. 23, the data after FFT processed by each azimuth compression processor 2 is stored in the shared memory 4, and then the range coverage is When performing the correction, a configuration is adopted in which the data after FFT stored in the shared memory 4 is referred to.

Each azimuth compression processor 2 has a function of ((n / M)
× m) data is input, one line of data in the azimuth direction, that is, m data are taken out,
On the other hand, the FFT processing is performed, and the data after the FFT is stored in a predetermined position of the shared memory 4. This is (n /
By repeating the process M) times, the FFT processing is performed on all the input data, and all the results are stored in a predetermined position of the shared memory 4.

Next, each azimuth compression processor 2
The desired data is read from the shared memory 4 according to the following curve, and is resampled on a straight line as shown in FIG. Thereafter, the data is subjected to complex multiplication and IFFT processing, and the azimuth compression processing is completed.

FIG. 24 shows, for example, Japanese Patent Application Laid-Open No. 58-1
FIG. 9 is a block diagram illustrating another configuration example of a conventional SAR signal processing device described in Japanese Patent Application Laid-Open No. 91979. In the figure, reference numeral 2 denotes an azimuth compression processor which performs the same azimuth compression processing as that shown in FIGS. 19 and 23. Reference numeral 5 denotes a range coverage correction specific memory arranged in each azimuth compression processor 2 for storing data after FFT, and 6 stores the FFT data in the range coverage correction specific memory 5 in another azimuth compression processor 2. This is a shared bus for writing.

Next, the operation will be described. Here, in the conventional SAR signal processing device shown in FIG. 24, the data after the FFT processed by each azimuth compression processor 2 is transferred to another azimuth compression processor 2 using the shared bus 6.
Are stored in the range-coverage correction specific memory 5 within the range, and then, when the azimuth compression processors 2 perform the range-coverage correction, after the FFT stored in the range-coverage correction specific memory 5 in each azimuth compression processor 2. It employs a configuration of referring to data.

Each azimuth compression processor 2 has ((n / M)
.Times.m) of data, one line of data in the azimuth direction, that is, m data, is taken out, FFT is performed on the data, and the FFT-processed data is shared using the shared bus 6. Is stored in a predetermined position of the range curvature correction specific memory 5 in the azimuth compression processor 2. By repeating this (n / M) times, FFT processing is performed on all input data,
The result is stored at a predetermined position in the range coverage correction specific memory 5 in each azimuth compression processor 2.

Next, each azimuth compression processor 2
The desired data is read from the range coverage correction specific memory 5 according to the following curve, and resampled on a straight line as shown in FIG. Thereafter, the data is subjected to complex multiplication and IFFT processing, and the azimuth compression processing is completed.

As described above, in the above-mentioned conventional SAR signal processing device, the observation data is divided into N parts in the azimuth direction,
The range compression processor 1 performs range compression processing in parallel, then divides the range-compressed data by M in the range direction, and performs M-azimuth compression processing in parallel by M azimuth compression processors 2. Therefore, at least each range compression processor 1 outputs a fraction of the observation data of the range compression processor 1, that is, (n × m / N) data, to each azimuth compression processor 2 at (n × m / M) of data. Therefore, it is necessary that the range compression processor 1 and the azimuth compression processor 2 have a large memory.

In particular, (n × m) observation data handled by the SAR is large and tends to increase year by year. In addition, the number of the range compression processors 1 and the azimuth compression processors 2, that is, N and M tend to decrease with the improvement of the processing performance of the processor. Therefore, the memory capacity required for the range compression processor 1 and the azimuth compression processor 2 tends to increase more and more, so that the range compression processor 1 or the azimuth compression processor 2 is limited in the available memory capacity. In this case, it is necessary to prepare more range compression processors 1 and azimuth compression processors 2 than the originally required number.

Here, suppose that the range compression processor 1 performs range compression processing on one line of data in the range direction, and outputs the result to the azimuth compression processor before starting processing for the next one line. 2, even if the memory capacity of the range compression processor 1 is reduced, the azimuth compression processor 2 cannot start processing until all the range compression processors 1 complete processing. Memory is required.

In addition, besides this, such a conventional SA
As a document in which a technology related to the R signal processing device is described, for example, a processing device corresponding to each signal processing stage of the SAR is allocated, and they are formed into a multi-stage pipeline and operated. Japanese Patent Application Laid-Open No. Sho 58-2, which makes it possible to operate the units in parallel and to use a two-dimensional addressing type image memory to eliminate the need for program-based rearrangement from corner turning processing.
No. 2982, storing all observational data or data in the middle of processing in a large-capacity memory so that vector processing can be performed at high speed by a pipeline method, and processing in the range direction and azimuth direction can be treated the same by addressing. Japanese Patent Application Laid-Open No. 61-120986 in which the corner turning process is unnecessary, and Japanese Patent Application Laid-Open No. 61-12098 in which the frequency band in the range direction and azimuth direction is limited by a digital filter to reduce the data amount and shorten the processing time. No. 210482 and the like.

[0025]

Since the conventional SAR signal processing apparatus is configured as described above, at least (n.times.m / N) data is stored in each range compression processor 1 and in the azimuth compression processor 2 in each range compression processor 2. At least (nxm
/ M) data, and a large memory is required for the range compression processor 1 and the azimuth compression processor 2. This tendency is more remarkable as the arithmetic performance of the processors is improved. Therefore, when the memory capacity that can be provided in the range compression processor 1 and the azimuth compression processor 2 is limited, the range compression processor 1 and the azimuth compression processor 2 are prepared in more than the originally required number. There was also a problem that it had to be done.

Further, in the conventional SAR signal processing device, when performing range migration correction, the processing result of the azimuth direction FFT processed by another azimuth compression processor 2 is required. 6, and the shared memory 4 and the shared bus 6 are commonly used by the M azimuth compression processors 2, so that there is a problem that a memory bottleneck and a bus bottleneck occur. .

Further, in the conventional SAR signal processing device,
Since all the azimuth compression processors 2 use the data after range compression processed by each range compression processor 1, a failure occurs in any of the range compression processors 1 and an erroneous processing result is output. If no processing result is output, an erroneous reproduced image is generated or reproduced even though the other range compression processor 1 and azimuth compression processor 2 are operating normally. An image cannot be generated at all, and in particular, when one of the range compression processors 1 outputs an erroneous result, the error is spread in the azimuth direction by the azimuth compression processing of the azimuth compression processor 2. However, there is a problem that the generated error is made larger.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. The present invention reduces the memory capacity required for a range compression processor and an azimuth compression processor, as well as a memory bottleneck generated for range migration correction. A SAR signal processing device that eliminates a bus bottleneck and prevents the influence of a failure from spreading to the entire apparatus when a failure occurs, or reduces or avoids the influence of the failure. The purpose is to:

[0029]

A SAR signal processing apparatus according to the present invention performs compression processing in a range direction and an azimuth direction on a given partial image to generate partial reproduced images in parallel with each other. Of the reproduction means
The partial image obtained by dividing the R observation data by the dividing means is distributed to appropriate reproducing means by the distributing means.

In the SAR signal processing apparatus according to the present invention, the dividing unit divides the specified necessary reproduction image area, and reproduces the SAR necessary to reproduce each of the divided partial reproduction images. The observation data area is obtained, and the observation data is divided into partial images.

In the SAR signal processing apparatus according to the present invention, the dividing means divides the observation data so that the size of each divided partial image is a power of two.

The SAR signal processing apparatus according to the present invention is such that the dividing means divides the observation data so that the processing amounts of the reproducing means for the divided individual partial images are equal to each other.

In the SAR signal processing device according to the present invention, the dividing means divides the observation data so that the size of each divided partial image or the memory capacity required by each reproducing means becomes equal to each other. It is something to do.

In the SAR signal processing apparatus according to the present invention, when the dividing unit divides the observation data into partial images, the division is performed such that the azimuth number of the reproduced image generated from the partial image is larger than the range number. It was made.

According to the SAR signal processing apparatus of the present invention, if the processing result of the partial image held in the data holding means provided for each of the reproducing means can be used for reproducing another partial image, The reproducing means utilizes the processing results held by the data holding means for the reproduction of other partial images, and the distribution means reproduces the processing results held by the corresponding data holding means so as to make effective use of the processing results. The distribution of the partial image to the means is performed.

The SAR signal processing apparatus according to the present invention can use the processing results held by the corresponding data holding means when distributing the partial images to the respective reproducing means. Is distributed to the reproducing means by the distribution means.

In the SAR signal processing apparatus according to the present invention, when distributing a partial image to each reproducing means, the SAR signal processing apparatus has the same range as the result of the compression processing in the range direction held by the corresponding data holding means. Is distributed to the reproducing means by the distribution means.

In the SAR signal processing apparatus according to the present invention, when the dividing means divides the observation data, the result of the range compression processing held in the data holding means is divided so that the reproducing means can use the result. It was done.

In the SAR signal processing device according to the present invention, the number of partial images, the location and size of each partial image, the reproducing means for processing each partial image, the processing status of each reproducing means, etc. Management information, and the management means refers to the management information held in the management information holding means,
The update is performed, and the operation of the entire SAR signal processing device is managed based on the management information.

In the SAR signal processing apparatus according to the present invention, when monitoring of the management information indicates that the processing of the partial image is not performed normally, the management means reproduces the processing of the partial image. The processing of the means is forcibly terminated, and the distribution means is instructed to redistribute the processing of the partial image to another reproduction means.

The SAR signal processing apparatus according to the present invention is provided with a plurality of management means having a function of forcibly terminating the processing of the reproducing means in which the processing of the partial image is not normally performed.

In the SAR signal processing apparatus according to the present invention, one of the plurality of management means refers to and updates the management information held in the management information holding means, and the other management means stores the management information. The management means performing reference and updating is monitored, and if a failure occurs in the management means, the failed management means is switched to one of the other management means.

In the SAR signal processing device according to the present invention, a function for exclusively referencing and updating the management information held by the management information holding means is provided to each of the plurality of management means, and the management thereof is performed. The means refers to and updates the management information in parallel with each other.

The SAR signal processing apparatus according to the present invention includes an output unit connected to each of the reproducing units, and outputs a partial reproduced image obtained from one or a plurality of partial images. is there.

In the SAR signal processing device according to the present invention, after the processing of all the partial images is completed, the output means outputs the reproduced image.

In the SAR signal processing apparatus according to the present invention, the output means outputs the partial reproduced image immediately after the processing by each reproducing means is completed.

In the SAR signal processing device according to the present invention, the output means is provided with a function of processing a partial reproduced image obtained from one or a plurality of partial images, and outputs the processed partial reproduced image. It was made.

[0048]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a block diagram showing a configuration of the SAR signal processing device according to the first embodiment of the present invention. In the figure, reference numeral 11 denotes a data division mechanism as division means for dividing observation data (input image) into a plurality of partial images. A plurality of units 12 are prepared and operate in parallel with each other, and perform a compression process in the range direction and the azimuth direction on the partial images divided by the data dividing mechanism 11, and generate a partial reproduced image for the given partial image. This is a data reproducing mechanism as reproducing means for generating. Reference numeral 13 denotes a data distribution mechanism as distribution means for distributing a plurality of partial images divided by the data division mechanism 11 to an appropriate data reproduction mechanism 12.

Next, the operation will be described. Here, the SAR signal processing device according to the first embodiment generates a reproduced image by processing the partial images divided by the data dividing mechanism 11 in parallel with each other and independently by a plurality of data reproducing mechanisms 12. The configuration is adopted.

Similarly to the conventional case, the SAR signal processing apparatus of the first embodiment has n pieces of observation data captured and input by the SAR in the range direction and m pieces of observation data in the azimuth direction as shown in FIG. It is assumed to be composed of data. The data division mechanism 11 divides the observation data into a plurality of partial images. FIG. 2 is an explanatory diagram showing the state of observation data divided by the data division mechanism 11 and the divided partial images. In the figure, 21 is a data dividing mechanism 1
Observation data (imaging data) divided by 1, 22
Is a partial image divided by the data dividing mechanism 11, and in the illustrated example, the observation data 21 is composed of nine partial images 2
It is divided into two.

As shown in FIG. 2, the data dividing mechanism 11
Observation data 21 is collected from multiple (9
) Partial images 22. Here, the amount of overlap can be specified in advance from the correlation length in the range direction, the moving amount in the range direction in the range migration correction, the correlation length in the azimuth direction, and the like. In the example shown in FIG. 2, the observation data 21 is divided into nine partial images 22, but the number of the partial images 22 may be larger or smaller.

When a plurality of partial images 22 are generated by the data division mechanism 11, the data distribution mechanism 13 distributes the partial images 22 to appropriate data reproduction mechanisms 12, respectively. It should be noted that which partial image 22 should be distributed to which data reproducing mechanism 12 may be fixedly determined in advance, or may be dynamically determined and determined by an operator.

Each data reproducing mechanism 12 is provided with the data distribution mechanism 1
3 is provided with the partial image 22, respectively, in parallel and independently of the other data reproducing mechanism 12.
The reproduction process is performed for. FIG. 3 is a flowchart showing a flow of a reproducing process for the partial image 22 in each of the data reproducing mechanisms 12. As shown in FIG. 3, the reproduction process for the partial image 22 in the data reproduction mechanism 12 can be performed by an algorithm substantially similar to the conventional reproduction process for observation data shown in FIG. Note that this is a generally known SAR
This is the nature of the image reproduction process.

Next, a description will be given of a reproducing process performed by each of the data reproducing mechanisms 12. The data reproducing mechanism 12 first performs FFT processing in step ST1 on the given one-line data in the range direction of the given partial image 22, then performs complex multiplication processing in step ST2, and performs IFFT processing in step ST3. Are sequentially executed. By repeating this process for each line in the range direction, the range compression process for all data of the given partial image 22 is completed.

The data reproducing mechanism 12 performs the FFT processing for each line in the azimuth direction in step ST4 on the data on which the range compression processing has been completed, and performs the azimuth FFT processing on all the data in step ST4. Complete. Next, proceeding to step ST5, the data reproducing mechanism 12 performs range migration correction on the data that has been subjected to the FFT processing in the azimuth direction. Then, with respect to the data resampled by the range migration correction, for each line in the azimuth direction, step ST
6 and the IFFT processing is sequentially executed in step ST7 to complete the azimuth compression processing.

Here, when the size of the given partial image 22 in the range direction is not a power of 2, the data reproducing mechanism 12 expands the data so as to be a power of 2, and then performs the FFT of the range direction. After the complex multiplication and IFFT processing are completed, the extended part is deleted. The same applies to the azimuth direction. If the size of the given partial image 22 in the azimuth direction is not a power of 2, the data after range compression is expanded before performing the FFT processing in the azimuth direction. , The part expanded after performing the IFFT processing in the azimuth direction is deleted.

When the processing in the data reproducing mechanism 12 is completed, the data distribution mechanism 13 distributes the unprocessed partial images 22 to the processed data reproducing mechanism 12, if any, if any. . The data reproducing mechanism 12 to which the partial image 22 has been given again restarts the reproducing process for the partial image 22. In this way, by performing the reproduction process on all the partial images 22, the image reproduction process on the observation data 21 is completed.

As described above, according to the first embodiment,
Since each data reproducing mechanism 12 only needs to prepare a memory having a capacity necessary for processing the given partial image 22,
The memory capacity can be reduced. Further, since the data reproducing mechanism 12 performs the range migration correction using the result processed by the own data reproducing mechanism 12,
A shared memory and a shared bus commonly used by a plurality of processors are eliminated, and a memory bottleneck and a bus bottleneck can be eliminated. Further, since the data reproducing mechanism 12 does not need the processing result of the other data reproducing mechanism 12 to generate the partial reproduced image corresponding to the given partial image 22, any of the other data reproducing mechanisms 12 Even if any trouble occurs, the effect is obtained such that a correct processing result can be output without being affected by the trouble.

If the data reproduction mechanism 11 can specify in advance the necessary reproduced image area, it is necessary to divide the specified reproduced image area and reproduce each of the divided partial reproduced images. By calculating the required area of the observation data 21, the observation data 21 may be divided into partial images 22. FIG. 4 is an explanatory diagram showing the state of the reproduced image obtained from the observation data 21 and the required reproduction image. In FIG.
The area 24 of the reproduced image obtained from 1 is a necessary area of the reproduced image. As shown in FIG. 4, when the required area 24 of the reproduced image is smaller than the area 23 of the reproduced image obtained from the observation data 21, the processing amount can be reduced.

The data dividing mechanism 11 may divide the observation data 21 so that the size of each divided partial image 22 becomes a power of two. By such division, the FF in the data reproducing mechanism 12
Since the expansion and deletion of data for the processing of T do not occur, the processing time can be reduced.

The processing amount of each data reproducing mechanism 12 is as follows.
It is possible to specify in advance from the partial image 22 to be given. Therefore, if the data dividing mechanism 11 divides the observation data 21 into the partial images 22 so that the processing amount of the data reproducing mechanism 12 for each of the divided partial images 22 becomes as equal as possible, the plurality of data reproducing mechanisms 12 Since the processing time between the SAR signal processing units is equalized, the operation rate of the entire SAR signal processing device can be improved.

The data dividing mechanism 11 determines the size of each divided partial image 22 or the data reproducing mechanism 1.
The observation data 21 may be divided so that the required memory capacity in Step 2 is as uniform as possible. By dividing the data in this manner, it is possible to suppress a wasteful memory capacity when a plurality of data reproducing mechanisms 12 are configured in the same manner.

Further, when the data dividing mechanism 11 divides the image into partial images 22 of a certain size, the reproduced image generated from the partial image 22 has as large an azimuth number as possible and a small number of ranges. It may be divided. FIGS. 5 and 6 are explanatory diagrams showing the area of the reproduced image generated from the partial image 22. In FIG.
2 is a range-compressed region, and 26 is a region of a reproduced image generated from the partial image 22. In each of the figures, the size of the partial image 22 and the area 26 of the reproduced image generated therefrom are the same, but FIG. 5 shows the case where the azimuth number of the area 26 of the reproduced image is larger than the number of ranges. FIG. 6 shows a case where the number of ranges is larger than the number of azimuths.

As shown in FIG. 5, when the number of azimuths in the area 26 of the reproduced image is set to be larger than the number of ranges, the data reproducing mechanism 12 performs range compression on all data of the partial image 22 and then performs the range compression. A part is discarded, and azimuth compression is performed only on a desired part. On the other hand, as shown in FIG. 6, when the range number is larger than the azimuth number, the data reproducing mechanism 12 performs range compression on all data of the partial image 22 and then performs azimuth compression on all data. , Some of which will be destroyed. That is, the area 26 of the reproduced image shown in FIG.
When the number of azimuths is increased, the data reproducing mechanism 12 is larger than when the number of ranges is increased as shown in FIG.
Can be reduced.

In the above description, the data distribution mechanism 13 gives the next partial image 22 after the processing in the data reproduction mechanism 12 is completed. During this, the next partial image 22 may be given. By doing so, the next processing can be started immediately after the processing in the data reproducing mechanism 12 is completed, so that the overall processing time can be reduced.

Embodiment 2 FIG. 7 is a block diagram showing a configuration of the SAR signal processing device according to the second embodiment of the present invention. In the figure, 11 is a data dividing mechanism as a dividing means, 12 is a data reproducing mechanism as a reproducing means, 1
Reference numeral 3 denotes a data distribution mechanism as a distribution means, which corresponds to those in the first embodiment shown by the same reference numerals in FIG. 14 are arranged in the respective data reproducing mechanisms 12 and the respective data reproducing mechanisms 1
2 is a buffer memory as data holding means for holding a result of the compression process in the range direction processed by 2 (hereinafter referred to as a result of the range compression process). The first embodiment is different from the first embodiment in that the data reproducing mechanism 12 uses the range compression processing result stored in the buffer memory 14 when it can be used when reproducing another partial image 22.
Is different from that of The data distribution mechanism 13
Is different from that of the first embodiment in that the partial images 22 are distributed so that the processing results of the range compression held in the buffer memory 14 of each data reproducing mechanism 12 can be effectively used.

Next, the operation will be described. Here, the SAR signal processing device according to the second embodiment employs a configuration in which each data reproducing mechanism 12 performs a reproducing process on a partial image by using a processing result of the range compression held in the buffer memory 14. Things.

First, the data dividing mechanism 11 sets the observation data 2
1 is divided into a plurality of partial images 22. This operation is performed in the same manner as in the first embodiment.

When a plurality of partial images 22 are generated by the data dividing mechanism 11, the data distribution mechanism 13 distributes the partial images 22 to an appropriate data reproducing mechanism 12.
This operation is performed in the same manner as in the first embodiment.

The data reproducing mechanism 12 has a data distribution mechanism 13
When the partial image 22 is provided from the, the reproduction process for the partial image 22 is started in parallel and independently of the other data reproducing mechanism 12. FIG. 8 is a flowchart showing a processing flow of the data reproducing mechanism 12 according to the second embodiment.

First, the data reproducing mechanism 12 executes step ST
At 11, it is confirmed whether or not the processing result of the range compression exists in the buffer memory 14. As a result, if it exists, the process proceeds to step ST12, and it is determined whether or not the range compression processing result held in the buffer memory 14 can be used for the reproduction processing on the partial image 22 to be processed now. .

In step ST11, when it is confirmed that the range compression processing result does not exist in the buffer memory 14, or in step ST12, it is used for the reproduction processing of the partial image 22 which exists but is to be processed now. If it is determined that the reproduction cannot be performed, the reproduction process is basically performed in the same manner as in the first embodiment. However, the following points are different. That is, the data reproducing mechanism 12 performs step ST1.
In step 3, range compression processing is performed on the given partial image 22. When the range compression processing is completed, step ST14 is performed.
Stores the processing result in the buffer memory 14. Thereafter, the process proceeds to step ST15, in which azimuth compression processing is executed to complete the reproduction processing.

On the other hand, if it is determined in step ST12 that the range compression processing result exists in the buffer memory 14 and that it can be used for the reproduction processing of the partial image 22 to be processed now, the data reproducing mechanism 12 It works as follows.

First, the data reproducing mechanism 12 executes step ST
At 16, whether there is an area of the range compression processing to be newly processed, that is, how much of the range compression processing result held in the buffer memory 14 can be used and which part is lacking Judge. as a result,
If there is an area to be newly processed, step S
The process branches to T17 to execute range compression processing on the given partial image 22. That is, for a given partial image 22, FFT, complex multiplication, and IFFT are performed for each line in the range direction corresponding to the region to be processed.
Is performed. When these processes are completed, the data after range compression is stored in the buffer memory 14 in step ST18. As a result, the buffer memory 14 holds all range-compressed data required for azimuth compression processing.

Next, proceeding to step ST19, the data reproducing mechanism 12 performs azimuth compression processing by referring to the range-compressed data held in the buffer memory 14, and completes this reproduction processing. If it is determined in step ST16 that there is no area for the range compression process to be newly processed, the process proceeds to step S16.
T17 and ST18 are skipped and the process branches directly to step ST19, where azimuth compression processing is performed to complete this reproduction processing.

When the processing in the data reproducing mechanism 12 is completed, the data distribution mechanism 13 distributes the unprocessed partial images 22 to the processed data reproducing mechanism 12 if there are any unprocessed partial images 22. . The data reproducing mechanism 12 to which the partial image 22 has been given again starts the reproducing process for the partial image 22 again. In this way, by executing the reproduction process for all the partial images 22, the image reproduction process for the observation data 21 is completed.

As described above, according to the second embodiment,
The data reproduction mechanism 12 stores the range compression processing result in the buffer memory 14 and processes the partial image 2 to be processed now.
If it is determined that it can be used for playback processing for 2,
By utilizing the processing result of the range compression, there is no need to perform some or all range compression processing,
The effect that the processing time can be shortened is obtained.

Further, when distributing the partial image 22, the data distribution mechanism 13 gives priority to the data reproduction mechanism 12, which can effectively use the processing result of the range compression held in the buffer memory 14, for the partial image. , The processing time can be reduced more effectively.

For example, FIG. 9 is an explanatory view showing an example, in which 21 is observation data, 22a is a partial image processed immediately before, 22b is a partial image adjacent to this partial image 22a in the range direction, 26a is a region of a reproduced image reproduced from the partial image 22a, 26b is a region of a reproduced image reproduced from the partial image 22b, and 27 is a range compression processing result held in the buffer memory 14. This figure 9
Is a partial image which has been processed by the data reproducing mechanism 12 immediately before, and the processing result 27 of the range compression is adjacent to the partial image 22a held in the buffer memory 14 in the range direction and has not been processed yet. 22 shows a state in a case where 22b exists.

In the state as shown in FIG. 9, if the unprocessed partial image 22b is preferentially distributed to the data reproducing mechanism 12, the data reproducing mechanism 12 does not newly perform the range compression processing. , The data of the range compression processing result 27 held in the buffer memory 14 can be used. As described above, by utilizing the processing result 27 of the range compression, it is not necessary to perform the corresponding range compression processing, so that the processing time can be reduced.

FIG. 10 is an explanatory view showing another example different from that shown in FIG. 9 above. In FIG.
22c is a partial image processed immediately before, 22d is a partial image adjacent to this partial image 22c in the azimuth direction, 26c
Represents a region of the reproduced image reproduced from the partial image 22c, 26
d is the area of the reproduced image reproduced from the partial image 22d, 2
Reference numeral 7 denotes a range compression processing result held in the buffer memory 14. FIG. 10 shows that the data reproducing mechanism 1
2, the result 27 of the range compression is adjacent to the partial image 22c held in the buffer memory 14 in the azimuth direction, and there is a partial image 22d that has not been processed yet. It shows the situation.

Even in the state shown in FIG. 10, when the unprocessed partial image 22d is preferentially distributed to the data reproducing mechanism 12, the data reproducing mechanism 12 performs a part of range compression processing. Without performing this, it is possible to use a part of the data of the range compression processing result 27 held in the buffer memory 14. As described above, by utilizing a part of the processing result 27 of the range compression, it is not necessary to perform the range compression processing for that part, and the processing time can be reduced.

Further, the data dividing mechanism 11
The observation data 21 may be divided so that the processing time of the entire R signal processing device is as short as possible. As described above, the data reproducing mechanism 1
2 can effectively utilize the range-compressed data held in the buffer memory 14, the processing time can be reduced. Therefore, in order to minimize the processing time of the entire SAR signal processing device, for example, the data reproduction mechanism 12 divides the observation data so that the data after range compression held in the buffer memory 14 can be used. Just do it.

FIGS. 11, 12 and 13 are explanatory diagrams for explaining an example of such a division of the observation data 21, in which 21 is the observation data, 22e and 22f, and 22g and 22h are the illustrations. Partial images, 26e and 26f are areas of the reproduced image, and 27 is the range compression processing result held in the buffer memory 14. Hereinafter, FIGS.
An example of a method of dividing the observation data 21 will be described with reference to FIG.

FIG. 11 shows a required reproduced image area 26.
12 and 13 show partial images 22e and 22f or 22g and 22h for generating reproduced images in the reproduced image regions 26e and 26f shown in FIGS.
It is shown. The area 26 of the reproduced image shown in FIG.
In order to generate the reproduced images of e and 26f, as shown in FIG.
22f, the data reproduction mechanism 12 outputs the range compression processing result 2 held in the buffer memory 14.
7 data cannot be used. On the other hand, as shown in FIG. 13, when the partial images 22 g and 22 h are generated, the data reproducing mechanism 12 can use the data of the range compression processing result 27 stored in the buffer memory 14. As shown in FIG. 13, the processing time can be reduced by dividing the observation data so that the data reproduction mechanism 12 can use the data after range compression held in the buffer memory 14. Here, it is needless to say that such division of the partial image can be applied to the first embodiment.

The data distribution mechanism 13 newly distributes the partial image 22 to the data reproduction mechanism 12 which can use the processing result 27 of the range compression held in the buffer memory 14. Only the area of the partial image 22 necessary for the range compression to be performed may be distributed. By doing so, the data reproducing mechanism 1
2 can be reduced, and the performance of the entire SAR signal processing device can be improved.

In the description of the second embodiment, the buffer memory 14 is provided in the data reproducing mechanism 12. However, the buffer memory 14 must necessarily be arranged inside the data reproducing mechanism 12. Not to mention, it goes without saying that the data reproducing mechanism 12 may be disposed outside the data reproducing mechanism 12 in correspondence with each data reproducing mechanism 12.

Embodiment 3 FIG. 14 is a block diagram showing the configuration of the SAR signal processing device according to the third embodiment of the present invention. The corresponding parts are denoted by the same reference numerals as in FIG. 1 and description thereof is omitted. In the figure, reference numeral 15 denotes the number of partial images 22 divided by the data dividing mechanism 11 as the dividing means, the location and size of each partial image 22, and each partial image 22 distributed by the data distributing mechanism 13 as the distributing means. Is processed by a plurality of data reproducing mechanisms 12 as reproducing means, and each of the data reproducing mechanisms 1
2 is a management information memory as management information holding means for holding management information for managing the processing status and the like in 2. Reference numeral 16 denotes a system management mechanism as management means for referring to and updating the management information stored in the management information memory 15 and managing the operation of the entire SAR signal processing device based on the reference and update. In the example shown in FIG. 14, the management information memory 15 is arranged in the system management mechanism 16.

Next, the operation will be described. Here, the SAR signal processing device according to the third embodiment has a configuration in which the management information of the SAR signal processing device is stored in the management information memory 15 by the system management mechanism 16 and monitored. .

In the third embodiment, the operations of the data division mechanism 11, the data distribution mechanism 13, and the data reproduction mechanism 12 are performed in the same manner as in the first embodiment, and the description thereof will be omitted. Omitted.

When a plurality of partial images 22 are generated by the data division mechanism 11 dividing the observation data 21, the system management mechanism 16 determines the number of the partial images 22 generated by the data division mechanism 11, Information such as the location and size of the partial image 22 is stored in the management information memory 15 as management information.

Next, when the individual partial images 22 are distributed to the data reproducing mechanisms 12 by the data distribution mechanism 13, the system management mechanism 16
Information such as which data reproducing mechanism 12 is given is stored in the management information memory 15 as management information.

Further, when the reproduction processing in each data reproducing mechanism 12 is completed, the system management mechanism 16
Information such as which partial image 22 has been reproduced by which data reproducing mechanism 12 is stored in the management information memory 15 as management information.

The system management mechanism 16 manages the operation of the entire SAR signal processing device by monitoring the contents of the management information held in the management information memory 15 regularly or irregularly. it can. In addition, by monitoring the contents of the management information, it is possible to cope with a case where some trouble occurs in the SAR signal processing device. For example, there is a partial image 22 that has not been processed yet,
If there is a data reproducing mechanism 12 that is not performing any processing, the system management mechanism 16 cannot distribute the divided image to the data reproducing mechanism 12 due to some trouble in the data distribution mechanism 13. Then, it instructs the data distribution mechanism 13 to transmit the partial image 22 that has not been processed yet and the processing status of the data reproducing mechanism 12 to restart the processing.

As described above, according to the third embodiment,
A system management mechanism 16 having a management information memory 15 is provided, the management information of the SAR signal processing device is held in the management information memory 15, and the content is monitored, whereby the S
The operation of the entire AR signal processing device can be managed, and an effect can be easily obtained even when a failure occurs.

Here, the system management mechanism 16 includes:
It is also possible to provide a function for forcibly terminating the processing of the data reproducing mechanism 12 so as to avoid a trouble occurring in the data reproducing mechanism 12 and to complete the processing. That is, after the data reproducing mechanism 12 starts the processing, for example, the processing of the data reproducing mechanism 12 does not end even though a sufficient time has elapsed to complete the processing. If the processing has not been performed, the system management mechanism 16 forcibly terminates the processing of the data reproducing mechanism 12 and performs data processing to redistribute the processing of the partial image 22 being processed to another data reproducing mechanism 12. An instruction is given to the distribution mechanism 13.

With this configuration, even if a failure occurs in one of the plurality of data reproducing mechanisms 12, the data reproducing mechanism 12 forcibly terminates the processing. The processing can be completed by another data reproducing mechanism 12 to which the partial image 22 has been redistributed.

In the above description, a case is described in which only one system management mechanism 16 including the management information memory 15 is arranged in the SAR signal processing device. SAR 16
A plurality of signal processing devices may be arranged. In the following, a SAR having such a system management mechanism 16 will be described.
Two representative examples of the signal processing device will be described.

One of a plurality of system management mechanisms 16 prepared in the SAR signal processing device is managed by a predetermined system management mechanism 16 in a management information memory 15 disposed therein. The operation of the SAR signal processing device is managed by referring to and updating the information. On the other hand, the other system management mechanism 16 is currently referring to and updating the management information in the management information memory 15.
The operation of the system management mechanism 16 is monitored.
If a failure occurs in the system management mechanism 16 that is currently referring to and updating the management information memory 15, one of the other normal system management mechanisms 16 monitoring its operation is notified of the failure. Is switched to the system management mechanism 16 which has become. The other normal system management mechanism 16 switched in this manner refers to and updates the management information in the management information memory 15 that the failed system management mechanism 16 has performed, instead of the failed system management mechanism 16, and updates the relevant SAR. Manages the operation of the entire signal processing device.

As described above, when a plurality of system management mechanisms 16 are arranged in the SAR signal processing apparatus, and a failure occurs in the system management mechanism 16 which refers to and updates the management information memory 15, Since the management information memory 15 is referenced and updated by one of the other normal system management mechanisms 16, even if a failure occurs in a certain system management mechanism 16, the failure can be avoided.

In the above description, the management information memory 15
One system management mechanism 16 that performs reference and update of the information is determined in advance, and the other system management mechanism 16 monitors it. If a failure occurs, the processing is performed by another normal system management mechanism 16. Although the proxy is shown, a plurality of system management mechanisms 16 provided in the SAR signal processing device may be configured to refer to and update the management information held in each management information memory 15. . In this case, a plurality of prepared system management mechanisms 1
6 always and exclusively refer to and update the management information in the internal management information memory 15 in parallel with each other, and each of the plurality of system management mechanisms 16 operates normally. And the operation of the SAR signal processing device.

In this case as well, a plurality of system management mechanisms 16
Of the SAR signal processing device or the management information memory 15 has a failure because each of them exclusively refers to and updates the management information memory 15 in parallel with each other. In this case, the other normal system management mechanism 16 can immediately perform the processing, so that the trouble can be avoided.

The management information memory 15 may include information other than the above-described management information. In such a case, the system management mechanism 16 may be configured similarly. Further, the management information memory 15 does not necessarily have to be arranged inside the system management mechanism 16, and it goes without saying that the management information memory 15 may be arranged outside the system management mechanism 16.

Embodiment 4 FIG. 15 is a block diagram showing the configuration of the SAR signal processing device according to the fourth embodiment of the present invention. The corresponding parts are denoted by the same reference numerals as in FIG. 1, and description thereof will be omitted. In the figure, reference numeral 17 denotes a data output mechanism as output means for outputting a reproduced image generated by the data reproduction mechanism 12 as reproduction means to the outside. Reference numeral 18 denotes a buffer memory which is arranged in the data output mechanism 17 and temporarily holds a reproduced image generated by the data reproducing mechanism 12.

Next, the operation will be described. Here, the SAR signal processing device according to the fourth embodiment adopts a configuration in which a reproduced image generated by the data reproducing mechanism 12 is output to the outside via the data output mechanism 17.

In the fourth embodiment as well, the operations of the data division mechanism 11, the data distribution mechanism 13, and the data reproduction mechanism 12 are performed in the same manner as in the first embodiment. Omitted.

When the reproduction process of the given partial image 22 is completed, the data reproducing mechanism 12 transfers the processing result, that is, the partial reproduced image corresponding to the partial image 22 to the data output mechanism 17. Here, since there are a plurality of data reproducing mechanisms 12 in the SAR signal processing apparatus, partial reproduced images are transferred from the plurality of data reproducing mechanisms 12 to the data output mechanism 17, respectively. Since the processing time of the reproduction process in each data reproducing mechanism 12 may vary depending on the given partial image 22, the partial reproduced images are not necessarily transferred to the data output mechanism 17 from the plurality of data reproducing mechanisms 12 at the same time. It does not come.

When the data output mechanism 17 receives the partially reproduced image transferred irregularly from each data reproducing mechanism 12 in this way, it determines whether or not the data is data to be output to the outside. As a result, if it is data to be output, the data of the partial reproduced image is temporarily stored in the buffer memory 18, and if not, the data is discarded.

Next, the data output mechanism 17 determines whether or not all of the reproduced image data to be output in the buffer memory 18 has been prepared. As a result, if all the data to be output is obtained, the desired data is extracted from the buffer memory 18 and output. If all the data to be output is not available, it waits for the missing data to be transferred from the data reproducing mechanism 12.

The information on which data should be output and which data should be discarded among the data of the reproduced image irregularly transferred from each data reproducing mechanism 12 is as follows.
It may be determined in advance, or may be dynamically specified by the operator.

As described above, according to the fourth embodiment,
Since the data output mechanism 17 determines whether to output the data transferred from the data reproduction mechanism 12,
If an instruction as to which data is to be output is issued only to the data output mechanism 17, the data can be output, and it is not necessary to instruct which data is output to each of the plurality of data reproducing mechanisms 12. Therefore, control can be facilitated, and even if data to be output is generated irregularly from a plurality of data reproducing mechanisms 12, control can be performed in comparison with data directly output from each data reproducing mechanism 12. Can be easily obtained.

In the above description, only the data to be output is stored in the buffer memory 18, but all the data transferred from each data reproducing mechanism 12 is temporarily stored in the buffer memory 18, After the reproduction process for the partial image is completed, the data of the reproduced image may be output to the outside. Thus, SA
Once all the reproduced images of R are stored in the buffer memory 18, this is effective when applied to a case where the observation area changes according to the situation.

In the above description, the data reproducing mechanism 12
Although the data stored in the buffer memory 18 is temporarily stored in the buffer memory 18, the data transferred from each data reproducing mechanism 12 may be immediately output to the outside without being stored in the buffer memory 18. By doing so, the data writing / writing to the buffer memory 18 is performed.
Since the time required for reading is not necessary, when it is desired to observe the entire area, the data from the data reproducing mechanism 12 is immediately output, and the processing time can be reduced.

Further, in the above description, the data output mechanism 1
Reference numeral 7 denotes a device that outputs the input data as it is, but it may be configured to output the result after performing predetermined processing. The data transferred from the data reproducing mechanism 12 is subjected to processing such as filtering and binarization, and then temporarily stored in the buffer memory 18 or directly output directly to the outside. As a result, desired image processing can be performed on the output reproduced image, and a more effective reproduced image can be obtained.

[0115]

As described above, according to the present invention, the partial image obtained by dividing the SAR observation data by the dividing means is distributed to appropriate reproducing means by the distribution means, and the divided images are given by the respective reproducing means. Since the partial images are configured to be compressed in the range direction and the azimuth direction in parallel with each other to generate the partial reproduced image, the memory of the reproducing means is prepared in an amount necessary for processing the given partial image. Thus, it is possible to obtain a SAR signal processing device capable of reducing the memory capacity, and furthermore, the reproducing means outputs the processing result of the other reproducing means in order to generate a partial reproduced image corresponding to the given partial image. Since it is not necessary, even if any trouble occurs in any of the other reproducing means, it is not affected by the trouble, so that it is possible to output a correct processing result, and it is also possible to output a shared memory. Because it becomes unnecessary also shared bus, there is an effect, such as a memory bottleneck, the bus neck can be eliminated.

According to the present invention, when an area of a required reproduced image can be specified in advance, the area of the reproduced image specified by the dividing means is divided, and each divided partial reproduced image is reproduced. In order to obtain the necessary observation data area and to divide the observation data into partial images, if the required reproduction image area is smaller than the reproduction image area obtained from the observation data, There is an effect that the processing amount can be reduced.

According to the present invention, since the observation data is divided so that the size of each divided partial image is a power of two, the expansion and deletion of data for the FFT processing occurs in the reproducing means. The effect is that the processing time can be shortened without performing the processing.

According to the present invention, the observation data is divided so that the processing amounts of the divided partial images by the reproducing means are equal to each other, so that the processing time between the plurality of reproducing means is equalized. This has the effect of realizing a SAR signal processing device with a high operating rate of the entire device.

According to the present invention, the observation data is divided so that the size of each divided partial image or the memory capacity required by each reproducing means is equal to each other, so that a plurality of reproducing means are provided. Are configured in the same manner, there is an effect that wasted memory capacity can be suppressed.

According to the present invention, when the observation data is divided into partial images, the image is divided so that the azimuth number of the reproduced image generated from the partial image is larger than the range number. Since a part of the reproduced data is discarded and azimuth compression is performed only on a desired part, there is an effect that the processing amount of the reproducing means can be reduced.

According to the present invention, if the processing result of the partial image held in the corresponding data holding means can be used in the reproducing process for another partial image, the reproducing means converts the processing result into another partial image. And the distribution unit distributes the partial image so that the processing result held by the data holding unit can be effectively used. Therefore, the processing result of the partial image is stored in the data holding unit. Exists, and if the processing result can be used for a reproduction process to be performed from now on, it is not necessary to perform a part or all of the range compression processing by utilizing the processing result, and the data holding unit holds the data. Since the partial images are preferentially distributed to the reproducing means that can effectively use the processing result, there is an effect that the processing time can be more effectively reduced.

According to the present invention, the partial images adjacent to each other in the range direction in which the processing results held by the data holding means can be used are distributed to the reproducing means corresponding to the data holding means. The reproducing unit can use the processing result held in the data holding unit without newly performing the range compression process, and the processing time required for the range compression process can be reduced accordingly. This has the effect.

According to the present invention, the partial image adjacent in the azimuth direction and having the same range as the result of the compression in the range direction held by the data holding means is distributed to the reproducing means corresponding to the data holding means. As a result, the reproducing means can use a part of the processing result held in the data holding means without performing a part of the range compression processing. There is an effect that the required processing time can be reduced.

According to the present invention, since the observation data is divided so that the processing result held in the corresponding data holding means can be used by the reproducing means, the processing time of the entire apparatus can be reduced. There is an effect that can be.

According to the present invention, management information such as the number of partial images, the location and size of each partial image, reproducing means for processing each partial image, and the processing status of each reproducing means is stored in the management information holding means. , The management means is configured to refer to and update the management information held in the management information holding means. By monitoring the management information held in the management information holding means, the SAR signal processing is performed. It is possible to manage the operation of the entire apparatus and to easily cope with a failure.

According to the present invention, the management means is provided with a function for forcibly terminating the processing of the reproduction means. If the processing of the partial image is not performed normally as a result of monitoring the management information, the function is terminated. Since the process of the reproducing unit is forcibly terminated and the distribution unit is instructed to redistribute the processing of the partial image to another reproducing unit, even if a failure occurs in any of the reproducing units. Thus, it is possible to avoid the obstacle, and there is an effect that the processing can be completed by another reproducing unit to which the partial image has been redistributed.

According to the present invention, since a plurality of management means having a function of forcibly terminating the processing of the reproduction means are prepared, each of the management means refers to the management information holding means, By performing the update exclusively and in parallel with each other, even if a failure occurs in one management means, it is possible to avoid the failure.

According to the present invention, one of the plurality of management means refers to and updates management information, and the management means is monitored by another management means. Since the management means in which the failure has occurred is switched to one of the other management means, even if a failure occurs in the management means that is managing the operation of the SAR signal processing device, the failure can be avoided. There is an effect that can be.

According to the present invention, each of the plurality of management means is provided with a function for exclusively referencing and updating management information, and the management means are configured to operate in parallel with each other. (1) Even if a failure occurs in one management means, the failure can be avoided.

According to the present invention, the output means connected to each of the reproducing means is provided so that a partial reproduced image obtained from one or a plurality of partial images is outputted therefrom. By instructing the output means to output the data, it is possible to determine whether or not to output the data from the reproducing means. Therefore, it is necessary to instruct a plurality of reproducing means on which data to output. And the control is simplified, and even if the data to be output is generated irregularly from a plurality of reproducing means, the control is easier than in the case of outputting directly from each reproducing means. There are effects such as being able to perform.

According to the present invention, since the output of the reproduced image from the output means is performed after the processing of all the partial images is completed, all the reproduced images of the SAR are temporarily stored in the buffer memory. Therefore, if the present invention is applied to a case where the observation area changes according to the situation, there is an effect that the processing becomes easy.

According to the present invention, the output of the partial reproduction image from the output means is performed immediately after the processing by each reproduction means is completed, so that writing / reading of data to / from the buffer memory becomes unnecessary. If the present invention is applied to the case where it is desired to observe the entire region, the data from the reproducing means is output immediately, and the processing time can be shortened.

According to the present invention, a predetermined processing is performed by the output means having a function of processing a partial reproduced image, and then the output is performed. Therefore, desired image processing is performed on the reproduced image to be output. This makes it possible to obtain a more effective reproduced image.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a SAR signal processing device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a state of observation data divided by a dividing unit and a divided partial image in the first embodiment of the present invention.

FIG. 3 is a flowchart illustrating a flow of an image reproducing process performed by a reproducing unit according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a state of a reproduced image obtained from observation data and a required reproduced image in the first embodiment of the present invention.

FIG. 5 is an explanatory diagram illustrating an example of a region of a reproduced image generated from a partial image according to the first embodiment of the present invention.

FIG. 6 is an explanatory diagram showing another example of the area of the reproduced image generated from the partial image according to the first embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a SAR signal processing device according to a second embodiment of the present invention.

FIG. 8 is a flowchart showing a flow of processing of a reproducing unit according to Embodiment 2 of the present invention.

FIG. 9 is an explanatory diagram showing an example of partial image distribution according to Embodiment 2 of the present invention.

FIG. 10 is an explanatory diagram showing another example of partial image distribution according to Embodiment 2 of the present invention.

FIG. 11 is an explanatory diagram illustrating an example of a required reproduction image area for describing an example of division of observation data according to the second embodiment of the present invention.

FIG. 12 is an explanatory diagram illustrating an example of a partial image for generating a reproduced image, for describing an example of division of observation data according to the second embodiment of the present invention.

FIG. 13 is an explanatory diagram illustrating another example of a partial image for generating a reproduced image, for describing an example of division of observation data according to the second embodiment of the present invention.

FIG. 14 is a block diagram showing a configuration of a SAR signal processing device according to a third embodiment of the present invention.

FIG. 15 is a block diagram showing a configuration of a SAR signal processing device according to a fourth embodiment of the present invention.

FIG. 16 is an explanatory diagram showing observation data captured by the SAR of the present invention and a conventional SAR.

FIG. 17 is a flowchart showing a flow of an image reproducing process in a conventional SAR.

FIG. 18 is an explanatory diagram showing resampling of the same range data distributed on a quadratic curve onto a straight line.

FIG. 19 is a block diagram illustrating an example of a configuration of a conventional SAR signal processing device.

FIG. 20 is an explanatory diagram showing division of observation data in the azimuth direction in a conventional SAR signal processing device.

FIG. 21 is an explanatory diagram showing division of observation data in a range direction in a conventional SAR signal processing device.

FIG. 22 is an explanatory diagram showing data after FFT processing required for range coverage correction in a conventional SAR signal processing device.

FIG. 23 is a block diagram illustrating an example of a configuration of a conventional SAR signal processing device.

FIG. 24 is a block diagram showing another example of the configuration of the conventional SAR signal processing device.

[Explanation of symbols]

11 data division mechanism (division means), 12 data reproduction mechanism (reproduction means), 13 data distribution mechanism (distribution means), 14 buffer memory (data holding means), 15
Management information memory (management information holding means), 16 system management mechanism (management means), 17 data output mechanism (output means), 21 observation data (imaging data), 22 partial images, 22b partial images adjacent in the range direction, 22d
Partial images adjacent in the azimuth direction, 24 required reproduction image area, 27 processing result of range compression.

Claims (19)

[Claims] A dividing unit that divides image data obtained by a synthetic aperture radar into a plurality of partial images; and a plurality of prepared and performed compression processes in a range direction and an azimuth direction on the given partial images. A reproducing unit that performs processing of generating a partial reproduced image corresponding to the given partial image in parallel with each other; and a distributing unit that distributes a plurality of partial images divided by the dividing unit to an appropriate reproducing unit. Synthetic aperture radar signal processing device comprising: 2. A method according to claim 1, wherein the dividing unit divides the specified area of the reproduced image and reproduces each of the divided partial reproduced images when a necessary area of the reproduced image can be specified in advance. 2. The synthetic aperture radar signal processing device according to claim 1, wherein an area of image data obtained by the synthetic aperture radar is obtained and the image data is divided into partial images. 3. The apparatus according to claim 1, wherein said dividing means divides the image data obtained by the synthetic aperture radar so that the size of each of the divided partial images is a power of two. Synthetic aperture radar signal processing device. 4. A dividing means, wherein a processing amount of a reproducing means for each divided partial image is equal to each other,
2. The synthetic aperture radar signal processing device according to claim 1, wherein the image data is divided by the synthetic aperture radar. 5. A dividing means for dividing image data by a synthetic aperture radar so that the size of each divided partial image or the memory capacity required by each reproducing means is equal to each other. 2. The synthetic aperture radar signal processing device according to claim 1, wherein: 6. When the division unit divides image data obtained by the synthetic aperture radar into partial images of a certain size, the number of azimuths of a reproduced image generated from the partial images becomes larger than the number of ranges. 6. The synthetic aperture radar signal processing device according to claim 5, wherein the signal is divided as follows. 7. A data holding means for holding a result of a compression process in a range direction performed on a certain partial image is provided for each of the reproducing means, and the reproducing means reproduces another partial image. When performing the processing, if the result of the range-direction compression processing stored in the data holding means can be used for reproducing the partial image, the result of the range-direction compression processing stored in the data holding means The distribution unit transmits the partial image to the reproduction unit that can utilize the result of the compression process in the range direction held by the corresponding data storage unit to reproduce another partial image. 2. The synthetic aperture radar signal processing device according to claim 1, wherein the signal is preferentially distributed. 8. The distribution means can use the result of the range-direction compression processing held in the data holding means associated with the reproduction means when distributing the partial image to each reproduction means. 8. A synthetic aperture radar signal processing apparatus according to claim 7, wherein the partial images adjacent to each other in the range direction are distributed to the reproducing means. 9. The distribution unit, when distributing a partial image to each reproduction unit, has the same range as the result of the compression process in the range direction held in the data storage unit associated with the reproduction unit. A partial image adjacent in the azimuth direction
9. The synthetic aperture radar signal processing device according to claim 7, wherein the signal is distributed to the reproducing means. 10. A dividing means for dividing image data by a synthetic aperture radar so that a reproducing means can use a result of a compression process in a range direction held by a corresponding data holding means. The synthetic aperture radar signal processing device according to any one of claims 1 to 9, wherein: 11. The number of partial images divided by the dividing means,
Management information holding means for holding management information such as the location and size of the individual partial images, processing means for processing each of the partial images, and the processing status of the playback means; and the management information holding means 2. A synthetic aperture radar signal processing apparatus according to claim 1, further comprising management means for referring to and updating the management information and managing the operation of the entire synthetic aperture radar signal processing apparatus based on the management information. . 12. A management means for monitoring management information held in a management information holding means, and when processing of a partial image is not performed normally, a reproducing means for processing the partial image. 12. The synthetic aperture radar signal processing apparatus according to claim 11, wherein the processing is forcibly terminated and the distribution unit is instructed to redistribute the processing of the partial image to another reproduction unit. 13. The image processing apparatus according to claim 12, further comprising a plurality of management units having a function of forcibly terminating the processing of the reproduction unit in which the processing of the partial image is not normally performed.
A synthetic aperture radar signal processing apparatus as described in the above. 14. A predetermined one of a plurality of management means refers to and updates management information held in a management information holding means, and the other management means includes a predetermined management means. In the case where a failure occurs in one of the management means, one of the other management means refers to and updates the management information in place of the management means in which the failure has occurred. 14. The synthetic aperture radar signal processing device according to claim 13, wherein: 15. Each of the plurality of management means has a function for exclusively referencing and updating the management information held by the management information holding means, and exclusively referencing and updating the management information. 14. The synthetic aperture radar signal processing device according to claim 13, wherein the processing is performed in parallel with each other. 16. An output means connected to each of the reproducing means, wherein one or a plurality of the reproducing means outputs a partial reproduced image obtained from one partial image or a plurality of partial images from the output means. 2. The synthetic aperture radar signal processing device according to claim 1, wherein: 17. The synthetic aperture radar signal processing device according to claim 16, wherein the output means outputs a reproduced image after processing of all partial images is completed. 18. The synthetic aperture radar according to claim 16, wherein the output means outputs the partial reproduction image generated by the reproduction means as soon as the processing by the reproduction means ends. Signal processing device. 19. An output unit having a function of processing one or a plurality of reproduction units on a partial reproduction image obtained from one partial image or a plurality of partial images. 17. The synthetic aperture radar signal processing apparatus according to claim 16, wherein the apparatus outputs a reproduced image.