Efficient FFT Based Multi Source DOA Estimation for ULA

An accurate and fast direction-of-arrival (DOA) estimation method for multiple targets in additive white Gaussian noise is presented in this paper, where the maximum number of sources’ DOA can be estimated is N/2 for N sensors. In the proposed method, the expression of each DFT bin is derived in polynomial form by using the consecutive multiplication. Then the linearity of DFT bins is used to calculate the DOA. Moreover, the complex-valued least squares framework is adopted to extend the proposed method for multiple snapshots. The effect of noise on DOA estimation is simulated. And simulation results validate the advantages of the proposed method.