存在传输时延差的多点协作多用户传输  

Multi-user coordinated multi-point transmission with different delays

作　　者：张秀军[1] 肖立民[1] 周世东[1] 王京[1] 

机构地区：[1]清华大学电子工程系,北京100084

出　　处：《东南大学学报（自然科学版）》2012年第6期1036-1040,共5页Journal of Southeast University：Natural Science Edition

基　　金：国家重点基础研究发展计划(973计划)资助项目(2012CB316002);国家自然科学基金创新研究群体资助项目(61021001);国家科技重大专项资助项目(2012ZX03003007);清华大学国际合作资助项目(2010DFB10410)

摘　　要：为了减少下行多点协作系统中各协作基站到用户之间时延差所引起的多用户干扰,提出了一种基于最大化信漏噪比准则的时延补偿方法.首先,根据反馈的信道状态信息和时延信息,基于最大化信漏噪比的优化准则,对每个用户在基站端的时延补偿量进行优化,并得到补偿量的闭式解;然后根据该补偿量,在基站端对发送给每个用户的信号进行频域上的相位旋转,实现时延补偿.虽然该方法是在高信干噪比条件下通过近似得到的,但由于综合考虑了用户的信噪比以及对其他用户的干扰,因而能够实现接近最优的时延补偿.仿真结果表明,该方法能够在各种不同的信噪比下有效地补偿时延差,使系统和速率提高到接近理想无时延差场景的水平,适合于实际的多点协作多用户系统.To decrease the multi-user interferences caused by the different delays from cooperative base stations to certain users in the downlink of coordinated multi-point（CoMP） systems,a delay compensation method based on the maximum signal-to-leakage and noise ratio criterion is proposed.Firstly,according to the feedback of channel state information and transmission delay information,the compensation amount for each user is optimized to obtain a closed form solution based on the maximum signal-to-leakage and noise ratio criterion.Then,the delay compensation for each user is realized by phase rotation of transmitted signals at the base station side in the frequency domain.Although it is derived by approximation at high signal-to-interference and noise ratio,the proposed method can achieve almost optimal delay compensation because of taking into account both the user＇s signal-to-noise ratio and the interference to other users.The numerical simulation results show that this method can effectively compensate the different delays at various signal-to-noise ratios and improve the system sum data rate close to that of the ideal scenario without delay differences.Therefore,it is suitable for practical multi-user CoMP systems.

关 键 词：多点协作 多用户系统 定时同步 迫零预编码 

分 类 号：TN92[电子电信—通信与信息系统]