Research On DOA Estimation Technology Of Wideband Polarization Sensitive Array

Array signal processing is currently widely used in many industries such as radar,electronics,communications,sonar and medical.Direction of Arrival Estimation(DOA)is a key analysis in array signal processing.Broadband signals are commonly used in current array system designs.Previous algorithms were limited to the field of narrowband signals.Therefore,DOA estimation algorithm based on wideband signals has important research significance.The traditional scalar electromagnetic sensor array can only obtain the angle of arrival information of the signal source,and the polarization parameters of the signal source carry a lot of important information.The polarization sensitive array can not only obtain the spatial angle of arrival information of the signal source,but also obtain the polarization information of the signal source.Most of the research on the estimation of DOA for polarization sensitive arrays is based on the narrowband signal model.However,with the continuous development of wideband signal technology,its application scope has gradually extended to polarization sensitive array.The DOA estimation technology based on wideband signal is still a research field to be further explored.In addition,non-linear arrays will be more flexible in practical applications and have better system performance under certain conditions,so they have good prospects for development and application value.In this thesis,the DOA estimation technology of wideband polarization sensitive array is studied,including:1.The classical narrowband algorithms MUSIC,Root-MUSIC and ESPRIT are analyzed and simulated respectively,and their performances are compared in terms of signal-to-noise ratio,signal correlation and etc.The main methods of DOA estimation for wideband signals are subspace algorithms,including ISM algorithm and CSM algorithm.The ISM and CSM algorithms are simulated,the method of choosing the focusing frequency of CSM algorithm is demonstrated.2.Based on polarization sensitive array,the joint estimation technology of DOA and polarization information of emitter is developed.Four-dimensional peak searching is converted to two-dimensional peak searching by Lagrange multiplier dimensionality reduction method and rank defect dimensionality reduction method,and the performance of the algorithm is analyzed by simulation experiments.3.Establish the unified signal model of wideband array and polarization sensitive array,carry out the DOA estimation research of wideband polarization sensitive array,complete the signal modeling and DOA estimation algorithm of wideband polarization sensitive array.The ISM and CSM algorithms of wideband arrays are combined with the rank loss dimensionality reduction algorithm of polarization sensitive arrays,and the algorithm is simulated and analyzed.4.For irregular wideband polarization sensitive arrays,a general fast DOA estimation technique is studied.Based on the DOA estimation manifold separation technique,using the periodicity of array steering vector,the steering vector of antenna array is approximated by Fourier series,and the relationship between the steering vector and a van der Monte structure vector is established.The research of fast DOA estimation technology for irregular array is carried out,and the simulation experiment is completed.