Volume Based Opportunistic Interference Alignment over Correlated MIMO IBC

Abstract

Wireless communications have evolved rapidly over the years and today they are present everywhere. A fundamental aspect of wireless communications is that they all share the same medium, so interference has always been an issue to be considered. Taking advantage of the multiuser diversity offered by ultra-dense networks (UDNs), the Opportunistic Interference Alignment (OIA) techniques have become a very attractive solution for the Multiple-Input Multiple-Output Interfering Broadcast Channels (MIMO-IBC). In conventional OIA techniques, each user measures the level of correlation of the interfering signals received by the adjacent cells, sends this information to the corresponding base station (BS) station through a feedback link, and then, the BS makes a decision of which user will attend at a given time in a decentralized way. In this article, an OIA technique based on the volume of the parallelepiped formed by the interfering signals is proposed. The simulation results show that the proposed technique achieves a substantial improvement over conventional techniques especially at high signal-to-noise ratio (SNR) under correlated channels; in addition, a complexity analysis is presented to demonstrate the feasibility of the proposed technique.