【作者】 来飞；

【导师】 姜文利；

【作者基本信息】 国防科学技术大学 ， 信息与通信工程， 2011， 硕士

【摘要】 利用多观测平台测量辐射源信号的到达时间差(TDOA)和到达频率差(FDOA)来确定辐射源的位置,是无源定位研究中的重要技术问题。针对多站时差频差定位方法的不足,可以采用基于互模糊函数映射(CAF-MAP)的时差频差定位方法,该方法则可以较好地处理多平台信号的时差频差累积问题和定位问题。但已有的互模糊函数映射方法仍需要目标的初始位置,且运算量大。本文提出了一种改进的CAF-MAP定位方法,采用多级时差频差查找表,有效克服了已有CAF-MAP需要初始解的问题。并将该方法推广到多目标情况。针对多目标问题中特有的多峰干扰问题,提出一种改进的多目标映射策略,有效解决了该问题。最后通过计算机仿真验证了本文方法的正确性和有效性,为多站时差频差的工程应用提供了有力的理论和算法支撑。第二章从多站时差频差定位的模型和原理从发,分析了多站时差、多站频差和多站时差频差定位的基本原理。研究了传统时差频差定位的两个主要过程:参数测量和定位解算。在此基础之上,对传统时差频差定位存在的不足进行了详细的分析和总结。第三章针对单目标时差频差定位,提出了一种改进的单目标多站CAF-MAP定位方法。针对不同的应用场景,提出了多次观测CAF-MAP定位方法以及多平台多次观测CAF-MAP定位方法。该方法可有效解决传统时差频差定位中的多平台累积困难的缺点以及已有互模糊函数映射方法需要初始解和运算量大等缺点。第四章针对多目标时差频差定位,提出了一种多目标CAF-MAP定位方法。首先提出了一种直观的多目标时差频差CAF-MAP定位方法。当目标距离近时,互模糊函数出现干扰,由此提出了一种改进的多目标时差频差CAF-MAP定位方法,该方法直接对互模糊函数进行多峰搜索,有效的消除了多目标之间的干扰,具有较强的工程应用意义。第五章构建了多站时差频差数字仿真验证系统。在此基础之上,针对通信信号和雷达信号,仿真不同的场景下改进CAF-MAP定位方法的定位性能,验证了本文提出的改进CAF-MAP算法的有效性。本文围绕传统多站时差频差定位中面临的不足为出发点,提出了改进的CAF-MAP定位方法,有效解决传统时差频差定位中参数测量和定位解算中问题,算法性能稳健,定位精度高,具有较广的工程应用前景。更多还原

【Abstract】 Passive source localization using time difference of arrival (TDOA) and frequency difference of arrival (FDOA) from different receivers is a widely applied localization method. This paper first analyses the defects of conventional localization method. For example, conventional localization method will changed with the number of receivers.This problem does not exist in the method of Cross Ambiguity Function Mapping (CAF-MAP). However, conventional CAF-MAP method need initialized location of source. The computing efficiency is not good. In this paper, we propose a modified CAF-MAP method, which utilizes multiple grades lookup table to conquer above problems. We then extend the modified CAF-MAP method to the case of multiple sources localization. The CAFs from different sources will fold each other when sources are close which resulting several false peaks. We then propose a modified mapping approach to avoid this problem. Finally, computer simulations corroborate the theoretical results and the good performance of the proposed method. The rest of the paper is organized as follow.Chapter 2 investigates conventional method of source localization using TDOA and FODA measurements and analyses the defects in the process of localization.Chapter 3 proposes a modified CAF-MAP method for single source localization. The method then is extended to the case of multiple observed time segments. The proposed method conquers the defects of conversation CAF-MAP method.Chapter 4 extends the modified CAF-MAP to the case of multiple sources localization. CAFs from different sources will fold each other when they are close. This will result several false peaks. We then propose a modified mapping approach to avoid the problem.Finally, we construct a digital simulation system and simulate the proposed method using communication signals and radar signals respectively. Computer simulations corroborate the theoretical results and the good performance of the proposed method. The proposed method enriches the framework of passive localization, and strongly supports the passive localization engineering.更多还原