Network model for MIMO systems with coupled antennas and noisy amplifiers

This work presents a framework for the analysis of mutually-coupled antennas in a multiple-input multiple-output system. The approach uses network theory to formulate the transfer matrix relating the signals input to the transmit antennas to the signals at the output of the receiver front end. This transfer function includes the coupled transmit and receive antennas, the multipath propagation channel, the receiver matching network, and a realistic noise model for the receive amplifiers. Application of the formulation to coupled dipole antennas characterized using full-wave electromagnetic analysis illustrates the performance gains possible from matching the coupled antenna/receive amplifier subsystem for minimum noise figure as compared to matching for maximum signal power transfer.