Accuracy of MIMO Channel Capacity Equation Based Only on $S$ -Parameters of MIMO Antenna

Since the evaluation of multiple-input multiple-output (MIMO) antennas requires full information of its complex radiation patterns as well as propagation channels, its design procedures and analyses are cumbersome and complicated in general. In this letter, the accuracy of a closed-form capacity formula for mean MIMO channel capacity is investigated, where the S-parameter of the antenna is needed but the antenna must be lossless. Numerical analyses show that this formula gives mean channel capacity with a good accuracy when the signal-to-noise ratio is sufficiently high.