摘要
复杂的应用场景下,平台速度不能保持恒定。加速度的存在增加了双基合成孔径雷达距离和方位向的耦合,使成像处理更加困难。论文提出了一种二维频谱的正交解耦合方法,以解决加速度下的双基SAR成像问题。首先利用Chebyshev多项式将斜距展开成幂级数形式,然后利用驻留相位原理和级数反演法(Method of Series Reversion,MSR)得到回波信号的二维频谱。在此基础上,将二维频谱中的耦合相位进行Chebyshev正交分解,以解除距离和方位的耦合。最终通过相位补偿实现聚焦成像。实验结果表明,该方法能有效克服加速度的影响,并提高目标的成像质量。理论推导和仿真结果验证了算法的有效性和可行性。
In complex application scenarios,the velocity of radar platform cannot be kept constant.The existence of acceleration increases the coupling of range and azimuth of bistatic SAR,which makes the imaging processing more difficult.In this paper,an orthogonal decoupling method of two-dimensional spectrum is proposed to solve the imaging problem of bistatic SAR under acceleration.Firstly,Chebyshev polynomials are used to expand the slant range into higher-order power series,which improves the accuracy of slant range approximation.Then,the method of series inversion is used to obtain the high-order approximate two-dimensional spectrum of echo signal.On this basis,the coupling phase terms of the two-dimensional spectrum are decomposed by Chebyshev orthogonal polynomials to eliminate the range-azimuth coupling.Finally,focus imaging is realized by phase compensation.Experimental results show that this method can effectively overcome the influence of acceleration and improve the imaging quality of point targets.Theoretical derivation and simulation results verify the effectiveness and feasibility of the algorithm.
作者
李梦慧
谭鸽伟
杨晶晶
徐熙毅
李彪
LI Menghui;TAN Gewei;YANG Jingjing;XU Xiyi;LI Biao(College of Information Science and Engineering,Huaqiao University,Xiamen,Fujian 361021,China)
出处
《信号处理》
CSCD
北大核心
2021年第1期75-85,共11页
Journal of Signal Processing
基金
华侨大学研究生科研创新基金(18013082027)
车载雷达信号处理(605-54319027)
华侨大学人才项目(605-50Y10216)。
关键词
双基SAR
CHEBYSHEV多项式
二维耦合
线性距离走动
多普勒线性相位
正交解耦合
bistatic synthetic aperture radar(BiSAR)
Chebyshev polynomials
2-dimensional coupling
linear range cell migration
Doppler linear phase
orthogonal decoupling
