基于导航卫星反射信号的距离-多普勒图信噪比增强算法  

Signal-to-noise Ratio Enhancement Algorithm for Range-Doppler Map Generated by Reflection Signals of Navigation Satellite

作　　者：曾凡喾 严颂华[1,2] 马秦生[1] ZENG Fan-ku;YAN Song-hua;MA Qin-sheng(School of Electronic Information,Wuhan University,Wuhan 430072,China;Institute of Aerospace Science and Technology,Wuhan University,Wuhan 430072,China)

机构地区：[1]武汉大学电子信息学院,武汉430072 [2]武汉大学宇航科学与技术研究院,武汉430072

出　　处：《科学技术与工程》2019年第35期290-297,共8页Science Technology and Engineering

基　　金：国家自然科学基金(41571420)资助

摘　　要：利用全球导航卫星系统(global navigation satellite system,GNSS)与地基接收机构成的双基地雷达探测水上目标,是监测水上交通的新兴手段。利用由地球静止轨道(geostationary earth orbit,GEO)卫星反射信号生成的距离多普勒(range-Doppler,RD)图来实现目标探测。为了提高RD图中运动目标回波信号的信噪比,提出了一种增强回波信号能量的算法。该算法首先将相邻距离元和多普勒元上的回波信号通过距离补偿和多普勒补偿搬移到弱回波信号的位置,然后通过信号累加提高回波信号的能量,从而达到增强信噪比的目的。描述了探测长江货轮的实验,实验结果表明经增强算法处理后,运动目标回波信号的信噪比平均提高了4 dB左右。这一结果验证了利用北斗GEO卫星探测水上目标的可行性。The use of bistatic radar consisting of global navigation satellite system (GNSS) and ground-based receiver to detect water targets is an emerging method of monitoring waterborne traffic. The range-Doppler (RD) maps generated by the reflection signals of geosynchronous orbit (GEO) satellite was used to achieve target detection. In order to improve the signal-to-noise ratio (SNR) of moving target's echo signals in the RD maps, an algorithm for enhancing the energy of the echo signals is proposed. The algorithm firstly moves the echo signals on the adjacent range unit and Doppler unit to the position of the weak echo signals by range and Doppler compensation, and then increases the energy of echo signals by signals accumulation, thereby achieving the purpose of enhancing the SNR. The experiment of detecting freighters on the Yangtze River was described. The experimental results show that the SNR of the echo signals of the moving target is increased by about 4 dB on average after processing according to the algorithm,which verifies the feasibility of using the Beidou GEO satellite to detect the water targets.

关 键 词：GNSS-R 信噪比增强 水上目标探测 北斗GEO卫星 

分 类 号：TP751.1[自动化与计算机技术—检测技术与自动化装置]