A Partition-based Scheme for IRS-aided MIMO Fading Channels: Outage and DMT Analysis.

In this paper, a partition-based scheme is investigated for multiple-input multiple-output (MIMO) fading channels assisted by an intelligent reflecting surface (IRS). In this scheme, the IRS elements are partitioned into sub-surfaces, which are periodically selected to assist the communication. Through the sequential activation of each sub-surface, an equivalent parallel channel in the time domain is produced. The proposed scheme has low implementation complexity and does not require knowledge of the channel state information. We analyze the performance of the proposed scheme in terms of outage probability and provide an expression for the diversity-multiplexing tradeoff. We show, through theoretical and numerical results, that the asymptotic performance of the considered network under the partition-based scheme can be significantly enhanced in terms of diversity gain compared to the conventional case, where a single partition is considered. Moreover, both maximum diversity and multiplexing gain can be achieved under certain conditions with respect to the number of elements in each sub-surface.