Multiplexing Gain of Variable-Rate MIMO Systems

Multiple-input multiple-output (MIMO) systems with adaptive modulation and coding (AMC) have a potential to approach the channel capacity. We analyze the multiplexing gain of variable-rate (VR) MIMO systems in a generic framework and derive a sufficient and necessary condition for a VR MIMO system to achieve any given multiplexing gain. A pragmatic way of predicting the multiplexing gain of a VR MIMO system based on the component modulation modes is obtained