Simulation on Delay of Several Random Access Schemes

To reduce power consumption in random access, channel-adaptive random access was suggested. With channel-adaptive random access, a remote station transmits a random access packet only when channel gain is greater than a predetermined threshold. Even thought a random access event is triggered, if channel gain is less than the threshold, the remote station waits to transmit the packet until the channel gain becomes greater than the threshold. Therefore, there is an additional delay compared to conventional random access. Previous researches showed that channel-adaptive random access has a trade-off between power consumption and delay. However, retransmission was not considered in the previous researches. Therefore, in this paper, random access delay is compared between conventional and channel-adaptive random access considering retransmissions.