Is precoding for massive MIMO systems well-analyzed?

Literatures on precoding for massive MIMO, one disruptive technology for enabling 5G, have been mainly about metrics such as capacity and peak-to-average reduction. But for practical systems, block error rate (BLER) is one essential parameter that decides whether the system can work properly. In this work, we consider BLER of different precoding methods, and find that when applied to OFDM based massive MIMO, existing precoding methods would hardly work if applied to multiple resource blocks (RBs). Then, we propose a precoding method that intends to minimize the inter-user interference over the subcarriers. Through numerical results, we show that with this method, precoding can now be performed on multiple RBs. Overall, we have shown that precoding analysis for massive MIMO still needs further careful investigations.