The Modified Method of DOA Estimation Based on Least Squares Fitting
Liu Zhi · Systems engineering and electronics · 2002
The paper studies the effect of rank deficiency in sampling temporal correlation matrix by the LSF method for Doppler signal DOA estimation under the assumption that the array manifold is unknown. In many practical applications, the degree of feeedom for the optimal solution seeking is too hight, leading to an unwilling ill conditioned problem which degrades the LSF based method severely. The paper, proposes several preprocessing schemes for solving the potential poor convergence problem involved in the original optimization procedure. It is also shown that selecting a solution with minimum morm for the optimization is reasonable and feasible. In addition, some other techniques such as rank restoring and rank reducing which result in a successful convergence in beamspace are also presented. In these methods, good convergence can be achieved with some preprocessing techniques. Simulation results show that the given modification methods are very effective.\;