Effect of Mutual Coupling on the Performance of Multielement Antenna Systems

In this paper, we investigate the signal-to-noise ratio (SNR) in the palm-sized multi-antenna communication systems. The presented analysis includes the mutual coupling on both, signal and thermal noise. We apply the Nyquist’s thermal noise theorem to determine the thermal noise behavior in the multi-antenna system and to confirm the partial correlation of thermal noise for antenna spacing lower then a one wavelength. Then, we develop a method for thermal noise power calculation for the multiantenna system with coupled antennae. Simulation results shows that SNR is underestimated if the effect of mutual coupling for thermal noise is not accounted.