Opportunistic feedback with multiple classes in wireless systems

摘要

An opportunistic feedback protocol with multiple access probabilities is proposed, where users are divided into several classes according to their measured channel state. Different random access probabilities are assigned to each class. All users compete to send a feedback message through random access if their scheduling metric exceeds a threshold. An analytical model is developed for evaluating the proposed feedback protocol in terms of the sum-rate capacity and the feedback load. The proposed feedback protocol achieves an asymptotic sum-rate capacity with a minimal amount of feedback information.