CTH11-1: Queuing Aspects of Multiantenna Multiple Access Channels

In this communication, we investigate the effect of spatial dimension in a Gaussian multiple access system and study its impact on the physical layer capacity and the end to end delay from a queueing theory perspective. For a multiple-input, single-output (MISO) multiple access channel, we derive conditions on the transmit power and number of transmit antennas for which additional users increase or decrease the capacity. The capacity as a function of the number of users is used for calculating the end-to-end delay. Numerical analysis on the end-to-end delay for a Rayleigh fading MISO channel with no channel state information at transmitter (CSIT) indicates that increasing the number of transmit antennas can actually increase the delay.