Performance Analysis for MmWave MIMO-SCMA Systems using Lens Antenna Array

Abstract

The recent concept of beamspace multiple input multiple output (MIMO) can significantly reduce the number of required radio frequency (RF) chains in millimeter wave (mmWave) massive MIMO systems without obvious performance loss. However, the number of supported users cannot be larger than the number of RF chains in hybrid MIMO architectures. To break this fundamental limit, we introduce the concept of sparse code multiple access (SCMA) with beamspace MIMO, then a useful upper bound on the average symbol error probability is obtained through the union bound. The bound is tight in beamspace mmWave MIMO-SCMA systems for high SNR regions. The analytical result is compared with simulations, and the results confirm the effectiveness of the analysis for mmWave MIMO-SCMA channels.