Indoor channel measurements and analysis of a large-scale antenna system at 5.6 GHz

Large-scale antenna systems provide a promising way to increase spectral and energy efficiency with a very large number of antennas at the base station serving many tens of users simultaneously. However, to a large extent, the theoretical performance relies on some fundamental assumptions of the radio environment, which need to be validated in realistic propagation scenarios. In this study we focus on indoor channel measurement and analysis in a large hall with a virtual 12×12 rectangular array. Key channel characteristics, such as the received power, delay spread, correlation between antennas and different user channels, condition number among user group channel matrix and system capacity, are analyzed and compared with previous works in outdoor and outdoor-indoor scenarios. The results show that the channel correlation between antennas and users decreases to some certain extent as the number of antennas increases, while system capacity does not show an obvious ceiling effect as the antenna number grows. Besides, the characteristics of indoor channel have differences from those in other scenarios.