Phase Corrected ICA for Uplink Massive MIMO

Channel state information (CSI) is fundamental to the performance of massive multiple-input multiple-output systems. However, systems that rely on pilots for the CSI estimation are susceptible to pilot contamination, as neighboring cells may reuse the same pilot sequences. Independent component analysis (ICA) has been widely used in recent studies to perform blind decoding, in order to circumvent the effects of pilot contamination. In this letter, we introduce a modified version of fastICA, the phase corrected ICA that reduces phase rotation on the estimated constellations, and thus, results in better performance of blind receivers. Through simulations, we show that our method significantly reduces symbol error rates compared to standard ICA based methods. Furthermore, we show that the increase in complexity is small at high signal-to-noise rate.