Inter-cell Interference Coordination for Uplink Non-real-time Data in CDMA Systems

CDMA systems, interference is one of very important criteria to evaluate system performance. Interference is classified into inter-cell and intra-cell interference. While the intra-cell interference is generated by mobiles sharing the same base station, inter-cell interference is generated by the mobiles connected to different base stations. Many inter-cell interference mitigation schemes have been proposed to improve system performance. Most of them focus only on the downlink transmission. As for the downlink transmission, only one mobile is allowed to receive data from the base station at a moment except the broadcast service. However, as for the uplink transmission, multiple mobiles may have access to the base station simultaneously. The uplink inter-cell interference management is, therefore more difficult and important than the downlink. In this paper, we propose the inter-cell interference coordination scheme for uplink non-real-time transmission. This scheme shuts down a cell that injects lots of interference. The design of this scheme is based on the assumption that each base station applies the proportional fairness (PF) algorithm to the scheduling of uplink packets. The simulation results show that we can achieve improved system throughput by applying the proposed scheme.