Dynamic power control in a wireless static channel subject to a quality-of-service constraint

A controller dynamically chooses a state-dependent transmission rate on a static, point-to-point wireless link by varying transmission power over time. The transmitter is modeled as a finite-buffer Markovian queue with adjustable service rates. That is, data packets arrive to the system according to a Poisson process, and packet size is exponentially distributed. The controller chooses a transmission rate from a fixed set A of available values, depending on the backlog in the system. The objective is to minimize long-run average energy consumption subject to a quality-of-service constraint, which is expressed as an upper bound on the packet drop rate. An explicit formula is developed for the optimal transmission rate as a function of the packet queue length.