MMSE vector precoding with joint transmitter and receiver design for MIMO systems

The transmitter side (Tx) vector precoding (VP) shows excellent performance. However, joint transmitter and receiver (Tx–Rx) design might achieve further improvement. In this paper, we propose a novel joint Tx–Rx VP for multiple input multiple output (MIMO) systems. A unitary matrix is used at the receiver to partially equalize the channel. We design the joint Tx–Rx VP with the minimum mean square error (MMSE) criterion and deduce the general closed-form solution. Then we apply several methods including the singular value decomposition, QR decomposition and geometric mean decomposition (GMD) to specify the general joint Tx–Rx VP design. Moreover, by using the extended channel, we achieve an improved scheme to obtain further performance gain. Simulation results show that the specification with GMD method outperforms the other specifications and the Tx MMSE VP. The improved joint Tx–Rx MMSE VP with GMD is superior to other MMSE VP schemes.