Research On Coherently Distributed Sources DOA Eatimation Algorithm Based On Beamspace

In wireless communication systems,DOA estimation can provide the crucial information for channel parameters estimation and localization.As a result,the accuracy of DOA estimation is of great importance.In the terms of this fact,the coherently distributed sources model is selected by this paper,since it is more reliable than traditional point sources model.In the context of massive MIMO,wireless communication systems are equipped with hundreds of antennas at the base station in order to obtain good antenna gain and array gain,which contributs to a dramatic increase in the computational burden for the DOA estimation algorithm.In terms of the above problem,the improvement proposed in this paper are as follows.Firstly,the method of dimension reduction is used to simplify the construction of two dimension coherently distributed sourdes model.And unitary ESPRIT algorithm is employed to estimate the DOA of sources,since this estimator has high precise and low computational complexity.Secondly,the standard Fourier vectors is utilized to transform the received singal to beamspace,and the DOA estimation is performed by ESPRIT approach in this paper.Appropriate slection matrix is crucial to construct the rotation invariant relationship in beamspace.However,it still has a higher complexity.And the direction parameters cannot matched automatically in this method.Finally,in terms of the above problems,the DFT vectors amd unitary ESPRIT method instead standard Fourier vectors and ESPRIT method respectively in this paper.The selection matrix decides beam selection and real values transformation,which contribute to reduce the complexity.The simulation results show that the proposed method has high percise and low computiaional complexity,and it can be applied to the massive MIMO systerms.