基于信道化的阵列信号方向估计及DSP实现研究

【作者】 易军；

【导师】 何子述；

【作者基本信息】 电子科技大学 ， 信号与信息处理， 2007， 硕士

【摘要】 随着电子、信息技术的发展,现代电子战要求侦察接收机必须要具有宽输入带宽、高灵敏度、高分辨率、大动态范围,能适应现代高密集的信号环境,能对接收到的数据实时或准实时处理的特点。本文就是基于一种新型的数字信道化接收机,利用DSP完成对信道化后的数据的后续处理,实现对信源的方向估计。传统的无线电测向方法有幅度比较法、相位比较法(干涉仪法)等。最近几十年,信号处理技术发展突飞猛进,利用阵列信号处理技术不仅可以实现对信源方向估计的超分辨,而且抗干扰性能也大大加强。同时随着集成电路制造技术的发展,DSP芯片性能大大提高。本文使用集成了4片DSP芯片21160的PCI接口数字信号处理板卡Hammerhead-PCI作为硬件平台,利用现代的阵列信号DOA谱估计技术,实现对宽带侦收信号分频段估计。文章针对要对信道化接收机接收的大量数据进行实时或准实时处理的要求,在DOA估计算法选择上,着重计算量与估计精度的综合考量。基于均匀线阵,在非相干源情况下,分别尝试采用了MUSIC算法、MVDR算法,完成对各个信道数据的分别测向;在相干源情况下,采用基于前向平滑解相干的MUSIC算法完成测向;基于均匀圆阵,采用MVDR算法,完成对信源方向的二维估计。本文还讨论验证了信道划分个数对估计结果的影响;讨论验证了阵元个数、信噪比、采样数据快拍数等因素对估计结果的影响;讨论验证了本文所涉及的空间谱估计系统对信源的分辨力。更多还原

【Abstract】 According to the development of electronic and information technology, modern electronic warfare requires receiver to have wide input band-width, the high sensitivity, the high resolution, the big dynamirange, to be adapt to the modern highcrowded signal environment, to have the real-time processing or sub-real-time processing characteristic. This article bases on one new kind of digital channelized receiver, realizes the source position estimation with DSP by processing the data which is received .The traditional radio direction finding methods include the scope-comparison method, the phase comparison method and so on. Recently, the signal processing technology have developted by leaps and bounds, we can estimate the direction of signals exactly by using the array signal processing technology, the resistance to interference also have been greatly strengthened. Meanwhile, along with the development of integrated circuit manufacturing technology, the DSP’s performance greatly enhances. In this article we use PCI-interfaceing digital signal processing board Hammerhead-PCI which have got 4 DSP 21160 in board as the hardware platform, to obtain the direction information of signals by using modern array signal DOA estimating technology.In view of real-time processing or sub-real-time processing, to choose the DOA estimate algorithm, we considerate both the quantity and the precision. Based on unit linear array, in the non-coherent source situation, we use the MUSIC algorithm, the MVDR algorithm, separately; in the coherent source situation, we use MUSIC algorithm with spatial smoothing. Based on unit circle array, we complete to estimate the two-dimensional direction of the signal sources with MVDR algorithm.This article also have discussed and confirmed how the changeable factors influent the estimation, including the number of channels divised, the number of array element, the signal to noise ratio, the length of sampling data. The minimum spatial distance between two signals which we can discriminate is also been discussed and confirmed in this article.更多还原