An unified interference suppression framework — Joint vector and lattice approach

Interference can be aligned in either vector space (MIMO) or signal scale (lattice). Existing literatures on interference alignment treat these two approaches separately. In this paper, a unified design framework of interference suppression is proposed for interference channel, where both vector alignment and lattice alignment are considered jointly. The framework could adapt the interference alignment mode (vector or lattice) dynamically according to the channel state information (CSI), therefore, bringing more “ optimization freedom” in transmission design. Moreover, since perfect interference alignment schemes are designed for infinite SNR, we allow the imperfect interference alignment in low to medium SNR regime, and formulate the joint precoder and equalizer design as a sum-MSE minimization problem. Finally, it´s shown by simulations that our proposed scheme has a significant performance gain over the conventional interference mitigation schemes in pure vector space.