EM based joint channel estimation and signal detection for V-BLAST in MIMO OFDM systems

Perfect channel estimation is crucial to the detection of the V-BLAST (Vertical Bell Laboratories Layered Space-Time). The performance of V-BLAST will degrade dramatically when there exists large channel estimation error. Conventionally, the channel estimation is processed independently from the V-BLAST signal processing. In this paper, we propose an EM based algorithm to detect the transmitted V-BLAST structured signals in MIMO OFDM systems while estimate the channel impulse response (CIR) iteratively. Simulation results show that compared with conventional channel estimation methods, this algorithm is bandwidth efficient and has better performance in fast fading multi-path channels.

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