MIMO channel statistics and signal processing in mode-division multiplexing systems

We review channel models for mode-division multiplexing (MDM) systems, the statistics derived from them, and their implications for system performance and complexity. We present the fundamentals of architectures and algorithms for multi-input multi-output (MIMO) equalization. With careful physical link design and judicious choice of signal processing architectures, the challenges of MIMO signal processing can be overcome in MDM systems.