Energy consumption performance of a class of access protocols for mobile data networks

Abstract

When user terminals powered by a finite battery source are used for wireless communications, energy constraints are likely to influence the choice of media access protocols. We use the average number of correctly transmitted packets for a given amount of allocated energy as an appropriate metric. In particular, we study different versions of a wireless access protocol operating over a mobile radio channel using a finite energy source with a flat power profile. The mobile radio channel itself is characterized by a correlated Rayleigh fading process, the correlation in the fading process being dependent on the speed of the user terminal. We show that the access protocol with an error detect feature is energy efficient for pedestrian user speeds, whereas for vehicular speeds a retransmission protocol is more efficient.