Analysis of Channel Capacity with Respect to Antenna Separation of an MIMO System in an Indoor Channel Environment

실내 채널 환경에서 MIMO 시스템의 안테나 이격거리에 따른 채널 용량 분석

  • Kim, Sang-Keun (Department of Electronic Information & Communication Engineering, Hongik University) ;
  • Oh, Yi-Sok (Department of Electronic Information & Communication Engineering, Hongik University)
  • 김상근 (홍익대학교 전자정보통신공학과) ;
  • 오이석 (홍익대학교 전자정보통신공학과)
  • Published : 2006.11.30


In this paper, the channel capacity of a specified wireless indoor multiple-input multiple-output(MIMO) channel is estimated by analyzing spatial characteristics of this channel using the three-dimensional ray tracing method, and a technique for deriving an optimized separation of multi-antenna elements is proposed. At first, the ray paths, the path losses, and the time-delay profile are computed using the three-dimensional ray tracing method in an indoor corridor environment, which has the line of sight(LOS) and non-line of sight(NLOS) regions. The ray tracing method is verified by a comparison between the computation results and the measurements which are obtained with dipole antennas, an amplifier and a network analyzer. Then, an MIMO system is positioned in the indoor channel environment and the ray paths and path losses are computed for four antenna-position combinations and various values of the antenna separation to obtain the channel capacity for the MIMO system. An optimum antenna-separation is derived by averaging the channel capacities of 100 receiver positions with four different antenna combinations.


Channel Capacity;MIMO System;Ray Tracing Method;Time Delay Profile


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