Moving Source Beamforming Reception with Nonlinear Filtering Methods for a Smart Antenna System

• Main Authors: Dai-Hua Chang, 張玳華
• Other Authors: Dah-Chung Chang
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/84798371269252799535

碩士 === 國立中央大學 === 通訊工程學系 === 101 === The beamforming technology can be used to cancel interference signals coming from different incident angles for a uniform linear antenna array. Some beamforming techniques have been well developed,in which the generalized sidelobe canceller (GSC) can adaptively adjust the beamforming pattern for the desired signal to obtain maximum signalto-interference-plus-noise ratio (SINR) and actually, it converts a constrained optimization beamforming problem into an unconstrianted one. Nevertheless, the GSC technique is very sensitive to the direction-of arrival (DOA) mismatch of the desired signal. In this thesis, we model the DOA mismatch or moreover, the DOA change due to a moving source,into the GSC structure. Using the state-space formulation, three nonlinear filtering algorithms, i.e., the extended Kalman filter, the unscented Kalman filter, and the particle filter, are developed and compared to solve the DOA mismatch or change problem in a decision feedback (DF) GSC beamforming structure. The actual DOA information is estimated by proposed algorithms and is provided to the GSC for improving SINR. From simulation results under the conditions of a fixed DOA mismatch and the DOA change, the proposed technique outperforms the least mean square(LMS) based DF GSC structure and achieves a nearly optimal SINR performance close to the Wiener solution.