Research Of Broadband Signal Wave Direction Of Arrival Estimation Based On Multi-stage Wiener Fiter

As an important part of spatial spectrum estimation,Direction of Arrival(DOA)can perform spectrum estimation on the received data by the array and obtain the important parameter of the source signal: the incident angle.The incident angle parameter can effectively locate the user's specific location.Whether it is in the mobile communication system or the radar positioning,DOA has a very wide range of applications.It can be seen that the study of the direction of arrival estimation has important significance in theory and practice.To meet the increase in the transmission rate of wireless communication systems,the Massive MIMO(Massive Multiple-Input Multiple-Output)system,a key technology proposed in 5G(5th generation mobile communication),has been drawn much attention from researchers in all directions.Because of its superior performance,Massive MIMO system has become the frontier research direction in recent years.In an actual mobile communication system,as the mobile service grows,the mobile communication service gradually expands from single voice communication to data and real-time image communication,and the signal bandwidth used for communication also develops from narrowband to wideband to provide higher-speedsignal transmission.For long time,the study on DOA estimation has been focused on narrow-band signals.The mismatch between theory and practice will limit the development of algorithm research.Therefore,in order to match the actual mobile communication,this paper studies the DOA estimation which use wideband signal.Because of the processing of the DOA estimation of wideband signals requires complex processing in the time domain and frequency domain of the signal,algorithms itself has a large amount of computation.Taking the timeliness of the application of the algorithm into account,and the application in Massive MIMO system in the future,this paper proposes a low-complexity DOA estimation method(Fast-Focus TCT algorithm based on MSWF,MRF-TCT algorithm).To reduce the computational complexity of TCT algorithm,this new method uses a fast focusing way to construct the focus matrix in the TCT algorithm by using signal subspace.And combined with Multi-Stage Wiener filter(MSWF),this new method uses MSWF recursion to quickly solve the signal subspace,further reducing the computational complexity of the algorithm and improving the timeliness of the algorithm.Under Massive MIMO system,adaptive MRF-TCT algorithm is proposed.Through simulation experiments,it is found that the recursion of the MSWF will introduce some interference after the scale of the array is extended to a certain extent,resulting in the failure of the DOA estimation.In order to solve this problem,in Chapter 5 of this paper the characteristics of MSWF has been studied,and proposesan MSWF-based adaptive fast-focus TCT algorithm(adaptive MRF-TCT algorithm)in Massive MIMO system.In this paper,a large number of simulation experiments are performed under different scenarios and environmental parameters for the proposed new algorithm.Simulation experiments show that the new algorithm can effectively estimate the one-dimensional angle information of the signal and can estimate the two-dimensional pitch and azimuth parameters of the signal in Massive MIMO system.