Power Allocation for Fading Channels with Peak-to-Average Power Constraints

Power allocation with peak-to-average power ratio constraints is investigated for transmission over Nakagami-m fading channels with arbitrary input distributions. In the case of delay-limited block-fading channels, we find the solution to the minimum outage power allocation scheme with peak-to-average power constraints and arbitrary input distributions, and show that the signal-to-noise ratio exponent for any finite peak-to-average power ratio is the same as that of the peak-power limited problem, resulting in an error floor. In the case of the ergodic fully-interleaved channel, we find the power allocation rule that yields the maximal information rate for an arbitrary input distribution and show that capacities with peak-to-average power ratio constraints, even for small ratios, are very close to capacities without peak-power restrictions. K. D. Nguyen and L. K. Rasmussen are with the Institute for Telecommunications Research, University of South Australia, Mawson Lakes Boulevard, Mawson Lakes 5095, South Australia, Australia, e-mail: [email protected], [email protected]. A. Guillén i Fàbregas is with the Department of Engineering, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ, UK, e-mail: [email protected]. This work was submitted in part at 2008 IEEE International Symposium on Information Theory, Toronto, Canada, July 2008. This work has been supported by the Australian Research Council under ARC grants RN0459498, DP0558861 and DP0881160. June 20, 2013 DRAFT 2