Link energy minimization for wireless networks

In this paper, we formalize the problem of minimizing the energy dissipated to successfully transmit a single information bit over a link, considering circuit power consumption, packetization and retransmission overhead, bit/packet error probability, and the duty cycle of the transceiver. We optimize the packet length and transmit power as a function of distance between the transmitter and the receiver for different modulation schemes. We propose a general unconstrained energy consumption model that provides a lower bound on the energy dissipated per information bit. A practical unconstrained physical layer optimization scheme is also provided to illustrate the utilization of the model. Furthermore, minimized energy consumptions of different modulation schemes are compared over an additive white Gaussian noise (AWGN) channel. We extend this general energy consumption model by considering two particular constraints: fixed average power and fixed average rate. We explore the impact of the average power and the information rate constraints on energy consumption and determine the optimum constellation size, packet length, and duty cycle.