Proportional Fair Scheduling Gains for AMC-Aware Systems under Heterogeneous Radio Conditions

This letter provides exact analytical expressions and simpler, but still very effective, approximations for the multiuser diversity gains associated with Proportional Fair (PF) opportunistic scheduling. The impact of Adaptive Modulation & Coding (AMC) and of heterogeneous user populations with different radio conditions on the downlink are taken into account. The analysis is applicable to all major fading models and is based on the notion of the scheduling gain, a quantity that captures throughput and fairness aspects relevant to a user served under a considered scheduling policy as part of a heterogeneous group of users. Exploitation of relevant characteristics in the AMC rate function gives rise to two distinct regimes, corresponding to "regular" and "very high" average SNR conditions. All users in each of these regimes have approximately equal PF scheduling gains.