| 摘要 |
Synthetic aperture radar is a known system for producing a high resolution image of the terrain under a moving platform, in which the effect of a large antenna (which would give high resolution in the direction of travel (azimuth direction)) is synthesized by processing together with suitable phase shifts a large number of radar returns from a smaller antenna for which the footprints overlap. In order to simplify the image processing task, which is preferably carried out at high speed and on the moving platform itself, according to the invention an azimuth processor comprises a plurality of data processing modules 351-35R/N, each associated with a different part of the (range line) samples of echo returns, for example, by virtue of being connected to successive sections 331 -33R/N of a shift register into which successive range lines are clocked. Each module 35i includes a memory 39i to store the sets of range line samples, a processing section 37i to azimuth process the samples contained in the memory. To accommodate the range migration effect whereby the range of a point on the terrain varies between different echo returns as the platform moves relative to the terrain, adjacent modules are interconnected by links 49i so that samples required for processing by a module and not contained in its memory may be obtained from another module.
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