Capacity analysis of compact MIMO system

Abstract

Mutual coupling effect affects capacity of compact MIMO system. Using scattering parameter matrix (S-Matrix), this paper analyzes capacity of compact MIMO system and makes simulations on capacity using three different structural antenna arrays and three matching networks. Numerical results based on method of moment (MOM) show that antenna space with half wavelength is the dividing point of tightly coupling and loose coupling. Polarization pattern and matching network can change the impact of coupling effect on capacity. Furthermore it indicates that multiport conjugate (MC) matching network is the best to reduce mutual coupling effect as well as enhance capacity of compact MIMO system. As to the antenna array, cross polarization does help to improve the capacity of compact MIMO system.