【作者】 姚剑；

【导师】 乔晓林；

【作者基本信息】 哈尔滨工业大学 ， 信号与信息处理， 2009， 硕士

【摘要】 常规单脉冲体制雷达,由于测角精度高而广泛应用于雷达对目标的跟踪中,但当多个目标落在同一距离分辨单元及同一波束内时,很难对多个目标进行区分,从而会导致对重要目标攻击或跟踪失败。目前复杂的阵列处理技术及多波束数字形成技术可较好的对多目标进行检测及定位,但对于常规单脉冲雷达而言,这仍是一个难题。本文主要研究了常规单脉冲雷达对多目标的检测与分辨技术。为了更好地理解多目标检测与分辨算法,本文首先在单脉冲雷达系统测角原理、目标雷达截面积起伏模型的理论基础上,对多目标的单脉冲雷达系统响应进行了详细的推导及仿真研究。仿真结果表明,常规单脉冲雷达不能实现对多目标的分辨及到达角的正确估计。其次,本文介绍了几种多目标检测及分辨算法,包括:基于Neyman-Person准则的广义似然比检测(GLRT)方法、两种基于角度差异的多目标分辨方法(矩方法、最大似然估计方法)。仿真结果表明,这几种算法都能够以较优的性能实现对多目标的分辨及到达角的正确估计。最后,在多目标对雷达系统影响、多目标检测与分辨算法研究的基础上,研究了信噪比未知时多目标分辨问题和慢起伏多目标分辨问题,提出了两种多目标到达角估计的新方法。仿真结果表明,所提出的两种方法能够较好的实现对多目标到达角的估计。更多还原

【Abstract】 The normal monopulse radar is widely used for tracking the target because of its high precision in angel measurement. However, it is difficult to resolve the multiple targets located in one resolution cell and the same beam, which will lead to the falure of tracking the important targets. At present, complex array processing technology and digital multi-beam formation technologies can detect and locate the multiple targets well. However, it is still a problem for normal monopulse radar. The paper aims to study the solution of detecting and distinguishing the multiple targets.Firstly, in order to comprehend the multi-target detection and discrimination algorithm better, the paper deduces and simulate the response of monopulse radar of multi-target in detail, based on the introduction of the principles of monopulse radar’s angle measurement and the model of radar cross section. The simulation results show that normal monopulse radar cannot resolve the direction-of-arrival of multiple targets correctly.Secondly, the paper introduces several algorithm of multi-target detection and discrimination, which includes the generalized likelihood test(GLRT) based on neyman-person criterion, two kinds of multi-target discriminations containing moment method and maximum likelihood estimation method based on angle difference. The simulation results show that the algorithm detect and estimate the direction-of-arrival of multiple targets in perfect performance.Finally, base on the above parts, the paper study the problem of the multi-target resolving with unknown signal-to-noise ratio and the problem of the multi-target resolving with slow fluctuation, and put forward two new methods of estimating DOA. The simulation results show the two new methods produced in the paper can estimate the DOA of the multi-target effectively.更多还原