Haar Compression for Efficient CQI Feedback Signaling in 3GPP LTE Systems

Frequency selective scheduling is an attractive feature in the 3GPP LTE system that allows optimum usage of the allocated spectrum. In order to support frequency selective scheduling in the downlink, the mobile user needs to feedback channel quality indication (CQI) of the downlink channel to the base station. Several CQI feedback scheme have been proposed for 3GPP LTE systems. We propose to apply Haar compression to distributed subband groups to reduce the CQI feedback overhead. The simulation results indicate that the distributed- Haar scheme achieves the best trade-off between the throughput performance and overhead reduction compared with other CQI feedback schemes. We also observe that the sensitivity in sector throughput performance to user mobility is approximately the same for all feedback methods considered in the paper.