Dynamic Subarray Architecture for Wideband Hybrid Precoding
in Millimeter Wave Massive MIMO Systems
Sungwoo Park, Ahmed Alkhateeb and Robert W. Heath, Jr.
to appear in Proc. of Global Conference on Signal and Information Processing (GlobalSIP), Dec. 7-9, 2016.
Hybrid precoding architectures can address the trade-off between achievable spectral efficiency and power consumption in large-scale MIMO systems. Most of the prior work on hybrid precoding focused on narrowband channels and assumed fully-connected hybrid architectures. In this paper, a closed-form solution for OFDM-based wideband hybrid precoding is developed for both fully-connected and subarray architectures in frequency selective channels. The closed form solution provides useful insights into how hybrid subarray structures should be designed. Based on that, we propose a novel technique that dynamically constructs the hybrid subarrays based on the long-term channel characteristics.