Interference Alignment: A Building Block of Coordinated Beamforming Transceiver Designs

Interference alignment (IA) has recently been used for the transceiver design of the K-user constant MIMO interference channel. Since this system is a coordinated beamforming system and there are other design criteria, it is important to evaluate IA transceiver designs in light of other designs. In this paper, relationships between IA and the MMSE, Max Min SI R, Max Sum Capacity, and Min BER transceiver designs are rigorously established for all S R’s and power constraints. A MMSE based transceiver design approach, applicable for general linear equality power constraints, is also proposed—the first such design for this system. It is used, along with some IA transceiver designs, to demonstrate numerically the derived relationships and to perform a comparison of the designs. One of the main conclusions is that IA is a building block of the traditional transceiver designs considered (MMSE, Max Min SI R, etc.) and generally should not be pursued alone.