Abstract
With adaptive transmission, the transmission rate and/or power are adaptively adjusted according to the channel realization, which leads to a variable amount of energy consumption for the transmission of the same amount of data. We propose an analytical framework to statistically characterize the transmitter energy consumption of adaptive transmission over fading channels. For slow fading scenario, we derive the probability density function (PDF) and cumulative distribution function (CDF) of energy consumption assuming continuous-time Markov channel model. For the fast fading case, we apply the statistical mixture model to obtain the approximate PDF of energy consumption. Selected numerical results are presented to illustrate and to validate the mathematical formulations.