A Low Complexity Frequency-domain Approach to SIMO System Identification

With a rapidly changing channel in mobile communications, there is a scarcity of data samples, posing a challenge to reliable system identification. To address the problem, this paper presents a low complexity frequency-domain approach to blind single-input multiple-output (SIMO) system identification. The proposed approach is straightforward in concept and takes advantage of the computational power of FFT (fast Fourier transform). As a result, the new method is very efficient and effective for short data sequences, for which second-order statistics (SOS) based subspace methods suffer performance deterioration. Therefore, the proposed approach is a desirable alternative to SOS-based subspace methods to achieve good performance when data sequence is inevitably short in certain practical applications