Opportunistic feedback assisted scheduling and resource allocation in OFDMA systems

Abstract

This paper proposes an efficient channel information feedback method to minimize feedback overhead without performance loss for orthogonal frequency division multiple access (OFDMA) frequency division duplexing (FDD) systems in time-varying channel. The proposed best M users' best L subbands feedback method can significantly reduce the feedback overhead. The proposed scheme utilizes the property of the proposed fair (PF) scheduler that most of the subbands are assigned to the users with high average SNR by time selectivity of channel and some high SNR subbands are assigned to the users by frequency selectivity. For adaptive implementation, the threshold assisted feedback method is proposed. In the numerical results, it is showed that the feedback overhead of the proposed scheme is about 12% of the full CSI feedback method with little throughput loss when the number of users is 50.