Projection Matching Pursuit based DoA Estimation Scheme and its FPGA Implementation

A low complexity direction of arrival (DoA) estimation scheme for adaptive beamforming is presented in this paper. The proposed scheme uses projection matching pursuit based approach to improve the accuracy of angle estimation. Instead of applying pseudo matrix inversion, QR decomposition is used to greatly reduce the computing complexity in finding the projection matrix. The simulation results on a 1X8 linear antenna array system indicate the root mean square (RMS) error of DoA estimations using a beamforming codebook (19 vectors and 5 degrees angular resolution) is merely 0.6 degree when SNR = 20dB. Based on the proposed scheme, a hardware accelerator design is developed. To enhance the computing throughput, various techniques including paralleliz ation and pipeline processing are adopted in the design. FPGA implementation result on a Xilinx XC7VX330T platform shows that the design can operate up to 110.4MHz and performs one estimate every 8.6 mu s.