Uplink Component Carrier Selection for LTE-Advanced Systems with Carrier Aggregation

Abstract

Carrier aggregation (CA) is one of the key features for LTE-Advanced. By means of CA, two or more component carriers (CCs) can be aggregated to form a much wider transmission bandwidth up to 100 MHz in order to meet the IMT-Advanced requirements. With CA, it is possible to schedule a user equipment (UE) on multiple component carriers simultaneously. From radio resource management (RRM) perspective, CC selection plays an important role in optimizing the system performance with CA. In this paper, we investigate the uplink resource allocation for LTE-Advanced Systems, i.e., how to assign CCs to different users, and how to do the power scaling for each user. A pathloss threshold based CC selection algorithm is proposed to distinguish between power-limited and non-power-limited LTE-Advanced UEs, and assign only one CC to power-limited LTE-Advanced UEs, while assign multiple CCs to non-power-limited LTE-Advanced UEs. Simulation results show that the derived pathloss threshold works effectively and efficiently compared to other thresholds, and the proposed CC selection algorithm can achieve much better performance in terms of cell edge, average, and cell center user throughput compared to blindly assigning all LTE-Advanced UEs on all CCs.