聚束SAR模式下ω-k和PFA算法的比较

Analysis and Comparison of ω-k and Polar Format Algorithm for Spotlight SAR

研究波数域算法(ω-k)和极坐标形式算法(PFA)两种聚束SAR成像算法,并对其进行了定性比较分析.将SAR回波信号的预处理分为时域去调频处理和频域匹配滤波处理,给出了与此相应的两种算法的不同实现形式,并对其信号模型和成像原理进行了比较,从残留视频相位(RVP)、算法的近似和假设以及插值等角度分析比较了这两种算法的性能.比较结果表明,去调频信号预处理方法极大地降低了信号处理量,但是存在残留视频相位(RVP);匹配滤波预处理不存在RVP,但计算量可观.

Investigates the properties of both ω-k and PFA （polar format algorithm） under the mode of spotlight SAR. Based upon classifying preprocessing of spotlight SAR echo signals as dechirp in temporal domain and matched filtering in frequency domain, the corresponding different implementations from the two algorithms are analyzed respectively and comparatively. Analysis and comparison are presented in terms of the residual video phase, impacts resulting from the approximation of the algorithms associated with, as well as interpolation. Dechirp can reduce the computation load substantially, yet RVP is unavoidable, RVP does not exist inherently in the case of matched filtering.