近距离超宽带调频连续波雷达非线性校正研究  

Nonlinearity Correction of Short Range Wideband FMCW Radar

作　　者：靳科[1] 赖涛[1] 李公全 王珽[1] 赵拥军[1] 

机构地区：[1]解放军信息工程大学导航与空天目标工程学院,河南郑州450001

出　　处：《信号处理》2017年第2期158-167,共10页Journal of Signal Processing

基　　金：国家自然科学基金(41301481)资助项目

摘　　要：调频连续波雷达凭借其结构简单、造价低廉等优势在目标探测与识别等方面体现出重要的应用价值,然而系统的非线性调制问题成为制约其性能的重要因素。传统的非线性校正方法能够在一定程度上估计非线性,但估计过程中的误差传递问题导致校正效果并不理想。基于该问题,本文提出一种基于多项式回归的方法实现非线性的准确估计。所提算法首先将非线性相位建模为多项式函数,然后通过多项式回归实现参数的联合估计,以消除误差传递问题。基于估计出的参数,通过时域重采样操作实现非线性的校正。仿真结果表明,所提算法不仅能够准确估计出多项式参数,而且在一定信噪比下比传统算法更接近克拉美—罗界。X波段FMCW雷达实测数据处理结果显示,本文所提算法可以有效消除非线性误差。Frequency-modulated continuous-wave（ FMCW） radar,as a kind of radar systems with lightweight,low cost and high resolution,has attracted widespread attention and already reflected tremendous applicable value both in military and civil use. However,the nonlinearity introduced by modulation is a bottleneck to the utilization of FMCW radars. Typical nonlinearity correction method can estimate the nonlinearity to a certain degree,whereas the problem of error propagation in the estimation processing leads to a defective nonlinearity correction. Focusing on this problem,a novel algorithm based on polynomial regression is proposed in this paper to estimate the nonlinearity accurately. The proposed algorithm models the nonlinearity phase as a polynomial function and estimates the corresponding coefficients jointly through the polynomial regression algorithm（ PRA）,so that the error propagation is avoided. Based on the coefficients estimated,the nonlinearity correction is implemented with the help of time resampling procedure. Simulation results of the proposed algorithm indicate that not only the nonlinearity can be estimated accurately,but also the estimation performance is closer to the Cramer-Rao lower bound（ CRLB） in high signal to noise ratio（ SNR）,compared with the conventional method. Real data processing result of an X-band FMCW radar indicates that the nonlinearity can be eliminated effectively with the proposed algorithm.

关 键 词：调频连续波 非线性校正 多项式回归 重采样 合成孔径雷达 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置]