Rate Optimization for Energy Efficient System with M-QAM

International audienceIn this paper, we have considered the optimizationof the data rate in the case of point-to-point transmissionwith M-ary quadrature amplitude modulation (M-QAM). Themain goal is to minimize the bit energy consumption under anaverage bit error rate (BER) constraint in additive white gaussiannoise (AWGN) and Rayleigh channel. With the evolution ofwireless communication towards shorter transmission distances,the circuit energy in system hardware becomes significant in thecomputation of the energy expenditure as well as the transmissionenergy. We use an accurate power model for the circuit energyconsumption. The total energy consumption is then formulated asa function of the constellation size, distance, bandwidth and otherchannel parameters. Optimal data rate is obtained in closed formexpression and the effect of bandwidth, distance and channel pathloss is studied