一种宽带大斜视STOLT插值及距离变标补偿方法

Range Scaling Compensation Method Based on STOLT Interpolation in Broadband Squint SAS Imaging

针对大斜视合成孔径声呐成像问题,该文推导了宽带大斜视条件下合成孔径声呐回波在径向和方位向2维波数域中的波数谱的解析表达式,指出了Stolt插值需要解决的距离波数谱卷绕以及成像后距离向上目标的相对距离缩小等问题,给出了距离波数谱卷绕时的Stolt插值方法,提出了距离波数变标因子的概念,并通过在距离空域中补偿距离波数变标因子引起的距离变标的方法,解决了大斜视角条件下Stolt插值引起的距离变标问题。点目标仿真数据和模拟回波数据处理验证了该文方法的正确性和有效性。

： Considering the problem of large squint synthetic aperture sonar imaging, the analytical expression of the wavenumber spectrum is analyzed in detail in the radial and azimuth wavenumber fields under the wide-band high-squint conditions. The spectrum winding and shrink in the distance wavenumber fields after the Stolt interpolation are pointed out, and the reduced relative distance between the target in the imaging result is also indicated, then the Stolt interpolation method for distance wavenumber spectrum winding is given. The concept of range wavenumber scaling factor is proposed, the method of compensating the scaling factor and the spectrum winding in the distance space are given. Finally, the problem of range scaling caused by Stolt interpolation under large oblique angle is solved by compensating the distance variable in distance space. Point object simulation data and simulated echo data processing verify the correctness and validity of the proposed method