优化DPC-MAB SAR性能的自适应阵列配置技术

摘要

Displaced phase centers multiple azimuth beam (DPC-MAB) synthetic aperture radar (SAR) effectively improves the high resolution wide swath (HRWS) observation capability of space-borne SAR systems, but signal reconstruction performance will deteriorate with the departure of real pulse repetition frequency (PRF) from the optimal one required by uniform sampling. On the benefit of flexible beam forming capability of active phased array antennas, the uniform sampling could be achieved for arbitrary PRF by adaptively adjusting the distance between receiving antennas, thus system performances on signal reconstruction,azimuth ambiguity to signal ratio and signal to noise ratio etc. Could be optimized. Depending on this kind of array configuration, a multiple-input multiple-output (MIMO) system is available as well to further expand system functions without any additional transmitting antenna.%偏置相位中心方位多波束(displaced phase centers multiple azimuth beam,DPC-MAB)模式有效地提高了星载合成孔径雷达(synthetic aperture radar,SAR)系统的高分辨大测绘带(high resolution wide swath,HRWS)观测能力,但是脉冲重复频率(pulse repetition frequency,PRF)偏离均匀采样要求的最优值时,信号重构的性能会有恶化.依赖于有源相控阵天线灵活的波束形成能力,通过自适应地调整相位中心间距可以实现任意脉冲重复频率下的均匀采样,从而使得系统在信号重构、方位模糊抑制比以及信噪比等方面的性能得以优化.依赖于这样的阵列配置,还能够在无附加独立发射孔径的条件下实现多发多收(multiple-input multiple-output,MIMO)系统,进一步扩展系统功能.