基于数字卫星信号的无源雷达关键技术研究

【作者】 王雄才；

【导师】 是湘全；

【作者基本信息】 南京理工大学 ， 通信与信息系统， 2004， 硕士

【摘要】 无源雷达在反隐形、反辐射导弹、反低空突防方面有诸多优势，因而成为当今雷达研究的一个重要方向。在国外，基于地面电视和调频广播的无源雷达已有实用化的产品，国内在这方面的研究也是如火如荼。然而，基于卫星信号的无源雷达研究却少见报端，仅有几篇关于利用模拟卫星电视信号和GPS卫星信号进行无源探测的报告，而且试验结果均不是太理想，这其中自有其系统实现方面的困难。但是，这种方案所突现出来的优势——比如卫星的绝对安全性、无目标盲区等，都促使我们进一步去研究它，去探讨解决问题的方法。 本文从全新的角度，利用数字音频直播卫星作为照射源，建立了简单的系统结构，并对其中的两个方面——目标定位和信号检测进行了不同程度的探讨，获得了一定的理论研究成果。 在对卫星辐射源介绍的基础上，本文提出了T1R3的定位方案，即对于三个独立的接收站，分别用双天线接收直达信号和回波信号，测得两信号的到达时间差(TDOA)，再利用椭球面相交法实现了目标定位。精度仿真结果表明该系统的定位精度是比较满意的。有关弱信号检测和时差提取的问题，本文从相关和循环平稳方法的角度分别进行了分析和比较，得出了两算法各自的优势和适用场合。仿真结果显示，如果采用单一的相关方法实现信号检测，长时间的信号积累是必须的，为了解决积累时间过长带来的实时处理问题，本文提出了多频道并行处理等思想来解决工程上的这个矛盾。本文还简要的提及系统结构和系统的其他关键技术，并和基于地面电台的无源雷达做了定性的比较。更多还原

【Abstract】 The passive radar has many advantages on anti-stealth, anti-radiation missile, anti-extra-low flight, so it become the important direction of radar study. The passive radar based on local TV/FM signal has been practical oversea, at the same time, much attention have been paid to it in homeland. However, we can seldom contact some reports about the passive radar based on man-made satellite signal, just several papers mentioned the similar system based on the satellite-borne of analog TV or GPS satellites signal, furthermore, the results of these experiment are not good, this result from the difficulty of realization. Yet with the outstanding superiority of this system, such as the absolute security for the satellite, no blind-area of the target etc, all of this motivates us to research it and find new approaches of solution.From a new aspect, this dissertation conceive the simple system based on the satellite illuminator for the digital audio broadcast(DAB) purpose, and discuss the two problems------target location and signal detection, obtaining some theory fruit at last.On the basis of introduction about this satellite signal, the dissertation bring forwardthe location method------T1R3, that is to say, the system includes three independentreceivers, each of them has two antennas to receive direct signal from satellite and reflected signal from target, the TDOA have been measured through the comparison between this two signals, and the target will be orientated by a complex algorithm . The GDOP simulation show that the system location precision is satisfied. About the signal detection, the dissertation compares the correlation method with the cyclostationary method, and shows the advantages of the cyclostationary method. The simulation indicate that a long time integration may be used to achieve enough processing gain by correlation method, and the idea about multi-channel parallel processing were proposed to solve the contradiction from real-time processing. This dissertation mentions the system structure and the other key technology at the same time, the comparison between the passive radar based on local TV/FM signal and the passive radar based on DAB satellite signal were given.更多还原