Balanced-Switching-Oriented Blind Interference-Alignment Scheme for 2-User MISO Interference Channel

This letter considers the number of mode-switching associated with reconfigurable-antenna-based blind interference alignment (BIA) scheme for a 2-user MISO interference channel (IC). It is assumed that each user is equipped with a single reconfigurable antenna, which can switch among multiple independent modes. The switching-oriented BIA (S-BIA) scheme was proposed to minimize the overall mode-switching operations of reconfigurable antennas at the receivers. However, in S-BIA, the receivers can have a significantly different number of mode-switching operations, thus some users may experience longer delays, resulting in unfairness on their QoS. In this letter, we consider a 2-user MISO interference channel and propose a balanced-switching-based BIA (BS-BIA) scheme, which balances the individual mode-switching operations of the two users while reserving the same number of overall mode-switching operations as that in systems with S-BIA. Mathematical proofs and simulations results concur and show that the proposed BS-BIA scheme can reduce the differences in the numbers of mode-switching operations between the 2 users while keeping the overall mode-switching operation numbers close to that of systems with S-BIA.