Feedback Compression Schemes for Downlink Carrier Aggregation in LTE-Advanced
With full Channel State Information (CSI) available, it has been shown that Carrier Aggregation (CA) in the downlink can significantly improve the data rate experienced at the User Equipments (UE). However, full CSI feedback in all Component Carriers (CCs) requires a large portion of the uplink bandwidth and the feedback information increases linearly with the number of CCs. Therefore, the performance gain brought by deploying CA could be easily hindered if the amount of CSI feedback is not thoroughly controlled. In this paper, the authors analyze several feedback overhead compression schemes in CA systems.