Abstract: The trunking systems based on TD-SCDMA network are limited by the interference that users create to each other. Conventional power control algorithm cannot eliminate adjacent group interference. The beamforming was used to suppress the interference outside the main lobe, the joint detection of multiple groups was conducted to remove both intragroup and intergroup Multiple Access Interference (MAI) in the lobe for the uplink receiver, then the two-step iterative power control algorithms were combined with joint detection to eliminate effectively the interference in the system, thus reducing system requirements on power control and improving the performance. The simulation results validate that the algorithm can effectively reduce the system transmission power and to suppress the interference.

Key words: Code Division Multiple Access (CDMA), trunking, power control, multiple user detection, beamforming

摘要： TD-SCDMA集群系统中存在各种干扰,传统的功率控制算法无法消除来自集群群组间的用户干扰。采用了先用波束赋形进行主波瓣外干扰抑制,然后进行多群组联合检测来消除波瓣内群组间干扰,再联合功率控制的两步迭代算法来进一步消除集群中的干扰,从而降低了系统对功控的要求,提高了性能。仿真结果证明,该算法能有效降低系统发射功率和抑制干扰。

关键词: 码分多址, 集群, 功率控制, 多用户检测, 波束赋形