低信噪比下线性/非线性调频信号距离超分辨  

A Novel Method for Super-Resolution in Range Domain of LFM/NLFM Signals at Low SNR

作　　者：刘晟[1] 向敬成[1] 

机构地区：[1]电子科技大学电子工程学院

出　　处：《信号处理》1999年第1期47-53,共7页Journal of Signal Processing

摘　　要：本文研究了应用高分辨阵列处理算法实现雷达距离超分辨问题。利用我们提出的针对线性／非线性调频（ＬＦ ／ＮＬＦＭ）信号的降噪算法，提高了回波信号的有效信噪比（ＳＮＲ）。通过将ＭＯＤＥ算法拓展到色噪声环境中，基于频域处理解决了不同目标速度接近时造成的目标回波强相关甚至相干给超分辨处理带来的困难。计算机模拟表明，本文方法可在低ＳＮＲ下实现多目标的距离超分辨估计，并克服了现有方法在ＳＮＲ门限、回波相干性、计算量等方面的限制。Linear or Nonlinear Frequency Modulation (LFM/NLFM) signals play a major part in modern ra- dar systems. Super-resolution in Range Domain of large time-bandwidth product LFM/NLFM signals at low SNR is investigated. A novel signal denoising algorithm based on FFT for LFM/NLFM signals used for preprocessing, which significantly the effective signal-to-noise-to-noise (SNR), is presented. We also extend the. MODE algorithm to deal with the color noise cases which are encountered due to roughness of in-band sped- trum when super-resolution estimation is made in frequency domain. Monte-Carlo simulation results are presented to illustrate the excellent performance of the proposed method.

关 键 词：距离超分辨 调频信号 低信噪比 雷达 

分 类 号：TN957.51[电子电信—信号与信息处理]