Multiuser detection in massive MIMO with quantized phase-only measurements

In this paper, we research the multiuser detection (MUD) in a new massive MIMO with quantized phase-only (PO) measurements. Because the phase quantization can be implemented by one-bit ADCs, PO-MIMO overcomes the ADC bottleneck that appears when the signal bandwidth reaches multi-giga Hertz. However, the new problem is how to complete the uplink multiuser detection (MUD) based on the quantized PO measurements. In this paper, it is firstly solved by the sum-product-algorithm (SPA). Based on central limit theorem (CLT) and Taylor expansions, the SPA detector (SPAD) is simplified as a new PO generalized approximate message passing detector (POG-AMPD). POG-AMPD can exploit the quantized phase measurements and signal prior probability distribution in a Bayesian manner. It involves matrix-vector multiplications, and some parallelized non-linear operations, so it is suitable for hardware implementation. Numerical results indicate that POG-AMPD approaches to the maximum likelihood (ML) detection performance. By adopting moderately more BS antennas, massive PO-MIMO can even performs similarly as the conventional massive MIMO with full measurements.