A Study of the Correlations Between Channel and Traffic Statistics in Multihop Networks

This paper investigates the correlations between traffic statistics and channel qualities and their impact on the performance of multihop networks. The physical channel is characterized by the probability of successful reception, which depends on the multiple access interference (MAI). Since a node contributes to interference only if it has a nonempty buffer upon being scheduled, the MAI is determined not only by the media-access-control (MAC) scheme but also by the traffic statistics. Therefore, the physical channel performance is intertwined with both the MAC scheme and the traffic statistics. We discuss the autocorrelation in the channels themselves and the cross correlation between the channel and traffic rates and derive closed-form expressions for the network throughput and capacity for -phase time division multiple access (TDMA) and slotted ALOHA. We also find that, in addition to the traffic rate, the traffic burstiness and correlation have a significant influence on . For smooth traffic, even without the MAC control, the traffic correlation could induce optimal spatial reuse like TDMA without the overhead of establishing and maintaining the frame structure. For bursty traffic, we propose an approach that employs a packet dropping policy and takes advantage of the traffic correlation to form a similar natural spacing as for smooth traffic.