A general algorithm for uplink opportunistic interference alignment in cellular network

This paper utilizes a new strategy to accomplish the general uplink opportunistic interference alignment (OIA) in cellular network. K cooperative cells are considered, each user and base station (BS) own N transmit antennas and M receive antennas respectively. The leakage interference is newly defined. Each user calculates the amount of the leakage interference and reports it to its corresponding BS which selects the optimum users for data transmission. The prior OIA approach, which totally depends on the channel randomness, requires numerous users to acquire multi-user diversity gain in each cell, but only a few users in each cell may have the opportunity for data transmission. The new method keeps the advantages of the existing OIA algorithm and derives a general OIA scheme with any transmit antennas. Simulation results indicate that the dependence on the channel randomness is dramatically weakened and better performance can be obtained, the system efficiency is improved a lot too.