Résumé: Opportunistic beamforming (OB) technique induces random fading, hence increases the performance of multiuser diversity greatly. However, if the number of active mobile stations (MS) is small, the performance of the OB technique is not so satisfactory. Moreover, the OB technique relies on the training sequences to estimate the real-time signal to interference plus noise ratio (SINR) of each activated beam (or weighting vector) for each MS, thus costs a large amount of radio resources. In this paper, we propose a new organised beam-hopping (OBH) technique which could achieve good performance in the scenarios of both large and small number of MSs, and highly reduce the uplink traffic and signal processing at the base station (BS). The throughput performance of the OBH-based system is analysed. In addition, based on the required quality-of-service (QoS) of the MS, we develop an adaptive transmission mode selection (ATMS) scheme for the OBH-based systems.

Langue: Anglais