Fundamental bounds on MIMO antennas
Antenna current optimization is often used to analyze the optimal perfor-mance of antennas. Antenna performance can be quantied in e.g., minimumQ-factor and maximal gain over Q-factor ratio. The performance of MIMOantennas is more involved and a single parameter is, in general, not sucientto quantify it. Here, the capacity of an idealized channel is used as the mainperformance quantity. An optimiz