Investigation of Uplink Performances Based on the Switched Beam Antenna Scheme in TDD-CDMA Systems
نویسندگان
چکیده
In this paper, the switched beam antenna array is analyzed and its model in the system level is presented firstly. Based on the combination of multi-user detection (MUD) and the switched beam antenna (SBA) techniques in the time division duplexing-code division multiplex access (TDD-CDMA) system, the uplink load is investigated and the corresponding advanced uplink admission control scheme based on SBA is proposed. The uplink load is impacted by many elements, such as MUD factor, antenna beam pattern and the number of main beams, and so on. The antenna beam partner and the number of main beams make more important influences than the MUD factor in the uplink performances. The proposed advanced admission control scheme is available for TDD-CDMA system and can provide optimum performance if the proper background noise rise threshold is set.
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تاریخ انتشار 2005