Research On DOA Estimation Algorithm Based On Polarization Sensitive Array And DSP Implementation

Polarization information is an inherent property of electromagnetic waves 。 The polarization-sensitive array can not only acquire the spatial information of the signal but also obtain the polarization information.In addition to the DOA(Direction Of Arrival)parameters of the signal,the polarization parameters are introduced in the parameter estimation,which makes the polarization sensitive array more advantageous than the scalar array in the field of array signal processing.Polarization-sensitive arrays differ from scalar arrays in that vector sensors are used.Currently,vector sensors are mainly divided into full-electromagnetic vector sensors and low-dimensional defective sensors.However,the full electromagnetic vector sensor is expensive and the coupling is not suitable for wideband signal processing.Therefore,this paper mainly studies the orthogonal dipole.Firstly,the algorithm of polarized MUSIC(Multile Signal Classification)is studied.Since the polarization-sensitive array has two-dimensional polarization parameters more than the scalar array,it is bound to increase the computational complexity of the algorithm when performing signal processing.Therefore,the dimensionality reduction operation of the polarization MUSIC algorithm is discussed.In addition,advantages of polarization-sensitive arrays was discussed in detail,and analyzed precision's influence on signal parameters by Cramer Rao Bound(CRB),and the performance advantages of polarization sensitive arrays compared to scalar arrays are illustrated by the analysis of angular accuracy and resolution.Secondly,for the problem that the uniform linear array composed of dipoles is estimated by the polarization MUSIC algorithm and the polarized ESPRIT(Estimation of Siganl Parameters via Rotational Invariance Techniques)algorithm,a dipole cross-linear array and Ratio-ESPRI algorithm are proposed.The array is a uniform linear array composed of orthogonal dipoles,Polarization information in the X,Y,and Z directions can be obtained by the two-channel orthogonal dipole.When processing the data,there is no separate polarization domain phase difference or spatial phase difference between the three-dimensional polarization information for DOA estimate,but the polarization domain phase difference and the spatial phase difference are processed jointly,and the signal DOA and polarization parameters are directly obtained by the ratio of different phase differences.The experimental simulation proves that the joint estimation of the two-dimensional DOA and polarization parameters of the signal can be effectively realized by using a uniform linear array,which can effectively save the layout space of the antenna.Finally,a uniform circular array of polarization-sensitive arrays is implemented using hardware.This algorithm is implemented by the multi-core DSP(Digital Signal Processing)processorTMS320C6678,the IPC and Data exchange used minimum use and sharedRegion.Because the polarization MUSIC algorithm has a huge amount of computation when doing spectral estimation,it is optimized according to the characteristics of multi-core DSP.The optimization strategy of search is mainly progressive hierarchical search and multi-core parallel search.