The Basics of Multiple Input Multiple Output (MIMO) Radio Systems

This article introduces the rationale and techniques involved with MIMO (Multiple-Input Multiple-Output)-based communication systems. The communication impairments due to multipath channels provide the base motivation for the application of the MIMO technique, and, in particular, the use of OFDM (Orthogonal Frequency Division Multiplexing) and spatial multiplexing for equalizing broadband wireless channels with non-selective fading.