Power Allocation for Discrete-Input Non-Ergodic Block-Fading Channels

Abstract— We consider power allocation algorithms for fixedrate transmission over Nakagami-m non-ergodic block-fading channels with perfect transmitter and receiver channel state information and discrete input signal constellations under shortand long-term power constraints. Optimal power allocation schemes are shown to be direct applications of previous results in the literature. We show that the SNR exponent of the optimal short-term scheme is given by the Singleton bound. We also illustrate the significant gains available by employing long-term power constraints. Due to the nature of the expressions involved, the complexity of optimal schemes may be prohibitive for system implementation. We propose simple sub-optimal power allocation schemes whose outage probability performance is very close to the minimum outage probability obtained by optimal schemes.

• Type: Journal
• Year: 2007
• Where: CORR
• Authors: Khoa D. Nguyen, Albert Guillen i Fabregas, Lars K. Rasmussen
• Keywords: CORR 2007, Education, Long-term Power Constraints, Optimal Schemes, Power Allocation