【作者】 李斌；

【导师】 侯春萍；

【作者基本信息】 天津大学 ， 通信与信息系统， 2004， 硕士

【摘要】 cdma2000是第三代移动通信系统中最具有竞争力的标准之一.其基本形式cdma2000 1X为现有IS-95A的改进形式,做到了与IS-95系统的完全兼容,具有良好的技术延续性,它支持先进的天线技术和更高的数据传输速率,在成熟性和可靠性上都有保障,因而成为从第二代向第三代移动通信平滑过渡中的最佳选择。本文使用Cadence公司的SPW(Signal Processing WorkSystem)EDA软件,完成了cdma2000 1X反向链路系统仿真模型的设计和实现工作,该模型基本实现了IS-2000协议所规定的cdma2000 1X中RC1至RC4的所有信道及信道的各种传输速率。发送分集技术是cdma2000中的一种关键技术,在发送分集中,信号既没有在时城内引入冗余,也没有在频域内引入冗余,因此发送分集没有降低频带利用率,这对高速传输特别有利。在多天线传输模式下,信号虽然在时域和频域没有引入冗余,但是信号被赋予了一定的空间结构,在空间域上引入了冗余,因此提高了传输性能。本文提出一种STBC(空时块编码)联合信道估计的发送分集新方式。STBC编译码结构简单,并可获得最大的分集增益。但是当在多径快衰落信道中使用STBC技术时,能量泄漏而引起的混叠现象将影响信道估计。因此,为了克服这种现象,本文采用了STBC结合导频信道的方式,将导频信道插入到业务信道之中,并在rake接收机中采用相应的算法进行信道估计,从而提高了系统的性能。更多还原

【Abstract】 Cdma2000 is one of the most competitive standards in 3G mobilecommunication system, and cdma2000 1X is the evolutionaryenhancement of IS-95A. cdma2000 provides full backward compatibilitywith IS-95, supporting good technical continuation, advanced antennatechnology and high data rate transmission. Be very stable and reliable,cdma2000 maybe the best way from 2G to 3G mobile system.This paper presents a design and implementation procedure for asimulation model of the cdma2000 reverse link, using Signal ProcessingWorkSystem (SPW) software simulation tools developed by Cadence.The model has been developed in a generic manner that includes all thereverse link four radio configurations and their corresponding data ratesaccording to the IS-2000 specifications.Transmit diversity is one of cdma2000 technologies. While using TD,no redundancy will be involved in time domain and frequency domain.This technology is supposed to contribute to high data rate transmissitionand not waste bandwidth, but bring space domain recundancy to thesystem.In this paper a new transmit diversity scheme will be assumed, whichis STBC with channel estimation. STBC has not only simple encoder anddecoder but also maximum TD gain, but while STBC encoded signaltransmitting through multipath fast fading channel overlap phenomenoninvoked by energy lost will affect channel estimation. In order to conquerthe phenomenon pilot shall be inserted to the traffic channel to aidchannel estimation in rake receiver.更多还原