Robust Transceiver Design Based on Interference Alignment for Multi-User Multi-Cell MIMO Networks with Channel Uncertainty

摘要

In this paper, we firstly exploit the inter-user interference (IUI) andinter-cell interference (ICI) as useful references to develop a robusttransceiver design based on interference alignment for a downlink multi-usermulti-cell multiple-input multiple-output (MIMO) interference network underchannel estimation error. At transmitters, we propose a two-tier transmitbeamforming strategy, we first achieve the inner beamforming direction andallocated power by minimizing the interference leakage as well as maximizingthe system energy efficiency, respectively. Then, for the outer beamformerdesign, we develop an efficient conjugate gradient Grassmann manifold subspacetracking algorithm to minimize the distances between the subspace spanned byinterference and the interference subspace in the time varying channel. Atreceivers, we propose a practical interference alignment based on fast androbust fast data projection method (FDPM) subspace tracking algorithm, toachieve the receive beamformer under channel uncertainty. Numerical resultsshow that our proposed robust transceiver design achieves better performancecompared with some existing methods in terms of the sum rate and the energyefficiency.