Diversity gain of millimeter-wave massive MIMO systems with distributed antenna arrays

摘要

Abstract This paper is concerned with diversity gain analysis for millimeter-wave (mmWave) massive MIMO systems employing distributed antenna subarray architecture. First, for a single-user mmWave system in which the transmitter and receiver consist of K sub t /sub and K sub r /sub subarrays, respectively, a diversity gain theorem is established when the numbers of subarray antennas go to infinity. Specifically, assuming that all subchannels have the same number of propagation paths L , the theorem states that by employing such a distributed antenna subarray architecture, a diversity gain of K sub r /sub K sub t /sub L ? N sub s /sub+1 can be achieved, where N sub s /sub represents the number of data streams. This result means that compared to the co-located antenna architecture, using the distributed antenna subarray architecture can scale up the diversity gain proportionally to K sub r /sub K sub t /sub. The analysis of diversity gain is then extended to the multiuser scenario as well as the scenario with conventional partially connected radio-frequency structure in the literature. Simulation results obtained with the hybrid analog/digital processing corroborate the analysis results and show that the distributed subarray architecture indeed yields a significantly better diversity performance than the co-located antenna architectures.