Research On Parameter Estimation Algorithm Based On Polarization Sensitive Array And FPGA Implementation

With the increasing demand for military and civilian applications,the research and application of direction of arrival(DOA)estimation have rapidly developed and become an essential component of many electronic warfare,playing a crucial role in tactical and strategic applications.The development of DOA estimation technology not only improves the efficiency and accuracy of electronic warfare,but also brings broad application prospects for civilian applications such as target tracking and sound source localization.With the continuous complexity of modern battlefield electromagnetic environment,the requirements for electronic countermeasures technology are becoming increasingly strict.In order to improve the antiinterference ability and DOA estimation performance of the passive radar direction finding system,a polarization sensitive passive direction finding system was established by utilizing polarization information.In this way,the system can simultaneously detect the spatial information and polarization information of the incident signal,thereby effectively improving the DOA estimation performance of the entire system.Firstly,this paper studies the theoretical basis of polarization sensitive arrays,mainly including the polarization concept and characterization of electromagnetic waves,the structure of polarization sensitive array elements and arrays,and the received signal model of polarization sensitive arrays.This provides a theoretical basis for subsequent research on joint estimation of DOA parameters and polarization parameters based on polarization sensitive arrays.Then,this paper delved into the joint estimation theory of DOA parameters and polarization parameters based on polarization sensitive arrays:(1)studied the signal parameter estimation formula when applying the multiple signal classification(MUSIC)algorithm to polarization sensitive arrays,and derived the dimensionality reduction principle of the algorithm;(2)The cost function formula of the deterministic maximum likelihood(DML)algorithm when applied to polarization sensitive arrays has been studied.In order to optimize the multidimensional iterative calculation of the DML algorithm,the algorithm principle of the alternating projection(AP)algorithm has been introduced,which transforms multidimensional parameter search into multiple one-dimensional parameter searches.The introduction of the Alternating Projection algorithm significantly reduces the computational burden of the DML algorithm;(3)The problem of joint parameter estimation for polarization sensitive arrays based on error models has been studied,and a received signal model based on error models has been proposed.The Signal Subspace Matching(SSM)algorithm has been combined with polarization sensitive arrays for the first time,solving the problem of joint parameter estimation based on error models.Combined with the AP algorithm,an iterative solution for SSM has been provided.Experiments have shown that when there are errors in the signal model,the signal parameter estimation performance of DML algorithm and SSM algorithm is significantly better than that of polarization MUSIC algorithm,while the performance of SSM algorithm is better than that of DML algorithm.Finally,based on distributed polarization sensitive arrays,this paper designs a FPGA implementation of the polarization MUSIC algorithm,and describes the implementation process of the algorithm in detail.A linear transformation method suitable for distributed polarization sensitive arrays is proposed.Realizing the complex data received by the array can help reduce the computational complexity of the algorithm,reduce the resource utilization and algorithm time consumption during FPGA implementation,and improve the real-time performance of the algorithm’s FPGA implementation.It provides a new hardware choice for the hardware implementation of DOA estimation algorithms.Compared to the traditional polarization MUSIC algorithm,this scheme significantly reduces the consumption of hardware and time resources,providing a new hardware choice for the hardware implementation of DOA estimation algorithms.