MIMO time reversal communications

Abstract

A time reversal mirror (TRM) exploits spatial diversity to achieve spatial and temporal focusing, a useful property for communications in an environment with significant multipath. Temporal focusing (pulse compression) mitigates intersymbol interference (ISI) while spatial focusing enables a straightforward extension to multiple-input/multiple-output (MIMO) communications. Furthermore, the time reversal process can be combined with adaptive channel equalization to remove the residual ISI and compensate for the channel variations, providing nearly optimal performance. At-sea experimental results for MIMO multi-access/multi-user communications demonstrate the effectiveness of time reversal communications in underwater acoustic channels.