TDD-based massive MIMO system with multi-antenna user equipments

In this paper, we present the link-level simulation of a time division duplex (TDD)-based massive multiple-input multiple-output (MIMO) system with multi-antenna user equipments (UEs). The system model of the proposed massive MIMO system is first given, based on which the general settings of our link-level simulation are presented, including the essential parameters, the LTE-like frame structure, and the discontinuous pilot allocation for all UEs. Block diagrams are then illustrated, along with the link-level data transmission procedures of both the uplink and the downlink. Thereinto, the low-complexity but well-performance channel estimation algorithm and the MIMO detector for the uplink are introduced, and two block diagonalization (BD) precoding schemes for the downlink are also illustrated. Finally, numerical results in terms of the bit error rate (BER) and the throughput are investigated and analyzed. Running time for these two proposed precoding schemes is also given for comparison of computational complexity.