Optimal and sub-optimal power and rate allocation for random ALOHA networks

Resource allocation is one of the most important mechanisms for performance optimization in Wireless Ad-hoc Networks (WANETs). In this work, we derive and analyze an optimal power and rate allocation strategy for random ALOHA WANETs where each transmitter only knows its desired channel gain. Assuming that the nodes are distributed according to a homogenous Poisson point process (PPP), we analyze the performance for both the outage model (which requires both power and rate allocation) and the ergodic model (which requires only power allocation). Comparison to sub-optimal schemes reveals that this scheme can lead to a significant performance gain compared to traditional power and rate settings. On the other hand, we advocate the use of the simple threshold scheduling scheme for power allocation and linear rate adaptation for rate allocation.  We derive performance lower bounds that prove, for any channel fading, that these schemes are close to optimal. We also present simulation results over Rayleigh fading channels that show a maximum loss of 1.5% between the advocated schemes and the optimal schemes.

* M.Sc. research supervised by Dr. Itsik Bergel