FFT-based conjugate gradient method for optimal STAP

A fast conjugate-gradient iterative algorithm (CGIA) for solving optimal space-time adaptive processing (STAP) problem is proposed. The algorithm is based on FFT by exploring the block Toeplitz with Toeplitz block (BTTB) structure of the interference covariance matrix. Therefore the computational complexity is significantly reduced as compared with the matrix inversion method. Computer simulations are provided for illustrating the effectiveness of the proposed method.