Channel Capacity of Distributed Antenna System Using Maximal Ratio Transmission

In mobile communication systems, the received signal power varies due to fading, shadowing and path loss, resulting in the transmission performance degradation. Transmit antenna diversity is a promising technique to improve the transmission performance. For the downlink transmission, the outage probability in a service area can be improved by distributing the transmit antennas over the service area instead of using all of them at the same location (i.e., a base station). This is because the slowly varying local average received signal power due to the shadowing and distance-dependent path losses can be mitigated. In this paper, we evaluate the channel capacity distribution obtainable a distributed antenna system (DAS) using maximal ratio transmission (MRT) diversity. We discuss the effects of the number of antennas, path loss exponent, and shadowing loss standard deviation on the distribution of channel capacity. Keywords-Maximal ratio transmission, distributed antenna systems, channel capacity