针对机载稀疏阵列天线雷达的空时杂波谱特性进行了研究,发现不同的稀疏方法和时域脉冲数都对杂波协方差矩阵的秩以及杂波谱有影响。提出在稀疏后的阵列中如果在任意两个阵元间所含的半波长的个数小于等于时域脉冲的个数,且同时保持总的阵列孔径不变,那么无论稀疏后阵列中还剩余多少个有效阵元,杂波协方差矩阵的秩都保持不变。用数值仿真对多种稀疏方法下的阵列空时杂波谱进行了分析,数值结果与所提理论相一致。
An investigation of space-time clutter spectrum for airborne sparse array applications is given in both theory and simulation, and shown that both the rank and the spectrum of clutter covariance matrix are dependent on the sparse configuration as well as the number of temporal samples. The analysis finds that if the total aperture is unchanged and the number of half-wavelength included in any interelement spacing is lower than the number of temporal pulses, the rank of clutter covariance matrix remain unchanged, no matter how many active elements are remained. The numeric results show good agreement with the proposed theorem.