Achieving AWGN Capacity Under Stochastic Energy Harvesting
In energy harvesting communication systems, an exogenous recharge process supplies energy necessary for data transmission and the arriving energy can be buffered in a battery before consumption. The authors determine the information-theoretic capacity of the classical Additive White Gaussian Noise (AWGN) channel with an energy harvesting transmitter with an unlimited sized battery. As the energy arrives randomly and can be saved in the battery, code-words must obey cumulative stochastic energy constraints. They show that the capacity of the AWGN channel with such stochastic channel input constraints is equal to the capacity with an average power constraint equal to the average recharge rate.