摘要
研究了LFM雷达信号在频率、初始相位、包络幅度未知的条件下,接收端信号到达时间估计算法。算法先利用相关信号检测算法对来波信号进行起始时间粗估计,利用LFM在分数阶傅立叶变换域上形成的最佳能量聚集谱特性,估计出LFM信号的频率,构建参考信号,并恢复出相应的基带信号。在低信噪比下对基带信号进行Morlet小波变换,检测出基带信号的峰值所在位置作为信号的到达时间精确估计。给出了LFM信号频率估计算法,小波变换尺度选择原则,并同时推导出到达时间估计(TOA)的克拉美罗下限(CRLB)。计算机仿真实现LFM雷达信号到达时间估计,当信噪比到达8 d B,到达时间估计均方根误差小于1倍抽样间隔,提高了对LFM宽带雷达信号到达时间的估计精度。
A new algorithm was studied by the author to investigate the time of Arrival （TOA） estimation of wideband LFM signal when frequency , original phase, gains were unknown. The algorithm use correlation detection to estimate the arrival time. The property of LFM was used in fractional Fourier transform to estimate base-band signal. Through Morlet transform , the algorithm got the final precise TOA. The final result has been analysis , and providing CRLB. Computer simulation verified theeffectiveness of the new method.
出处
《电子设计工程》
2017年第24期59-64,共6页
Electronic Design Engineering
基金
国家自然科学基金项目(61601296)
