一種易行的高分辨率機(jī)載SAR實(shí)時(shí)自聚焦算法
A Easy Implementation Real Time Autofocus Algorithm for High Resolution Airborne SAR
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摘要: 該文詳細(xì)分析了距離徙動(dòng)對(duì)頻移相關(guān)自聚焦算法的影響,得出了高分辨率時(shí)距離徙動(dòng)將嚴(yán)重影響頻移相關(guān)法估計(jì)精度的結(jié)論。并結(jié)合距離多普勒算法提出了一種基于距離門限制的頻移相關(guān)自聚焦算法,該算法減小了距離徙動(dòng)對(duì)自聚焦的影響,提高了估計(jì)精度,仿真和實(shí)際數(shù)據(jù)均驗(yàn)證了該算法的有效性,可以達(dá)到高分辨率的要求,并且具有計(jì)算簡(jiǎn)單的優(yōu)點(diǎn),適合實(shí)時(shí)成像。
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關(guān)鍵詞:
- 合成孔徑雷達(dá);頻移相關(guān)算法;實(shí)時(shí)成像;自聚焦處理
Abstract: The effect of the range migration to the Shift-And-Correlate Monopulse Secondary Surbeillause Redar (SAC) algorithm is analyzed in this paper. The conclusion is that the precision of SAC would be severely affected by the range migration in the high resolution SAR. Integrated with the range Doppler algorithm, a new SAC autofocus algorithm based on the limits of range bin is presented, which called Shift-And-Correlate within Gate Strategy (SACGS). The effect of the range migration is minished by SACGS. And the precision is increased. The efficiency of SACGS is proved by the simulation and actual SAR data. It can satisfy the request of the high resolution. And the computation is very simple, which make it very suitable for real-time image processing. -
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