OPTIMIZING DOWNLINK THROUGHPUT WITH USER COOPERATION AND SCHEDULING IN ADAPTIVE CELLULAR NETWORKS

摘要

With user cooperation, users act as relays for each other to provide extra diversity paths for improved performance. Relaying is performed for transmissions from a basestation to a mobile device according to a time division duplex (TDD) system either according to a downlink-assisted relaying (DAR) which performs a relaying operation in a defined supplemental downlink timeslot or according to an uplink-assisted relaying (UAR) which performs a relaying operation in a defined supplemental uplink timeslot. Relaying can be scheduled according to a max-throughput scheduling algorithm which achieves a maximum system throughput without imposing any fairness constraints on users or according to a round-robin scheduling algorithm which achieves absolute fairness in terms of delays among the considered users. The downlink throughput can be optimized from the basestation to the mobile device utilizing either amplify-and-forward (AF) or decode-and-forward (DF) cooperation protocols.