下行链路

• Through simulation we can see that wcdma system has a good performace under high bit rate service because of the advanced coding technology , we can also see that this performance is better in downtlink than uplink
  由此可以看出wcdma中编码技术的使用使其在高速率下有较好的链路特性，并且下行链路性能优于上行链路。
• This paper is responsible for multi - antenna receiving board and has finished the fpga design of synchronization and ofdm demodulation . simulation and testing results have proved the performance of b3g downlink
  第三章详细介绍了b3gtdd下行链路中同步技术和ofdm解调的算法原理,并从硬件实现的角度对其进行了一定的改进。
• Mimo precoding can reduce the receiver ’ s complexity , specially suited for the downlink of the cellular mobile communication system , so it has been noticed by the worldwide researchers these years
  Mimo预编码技术可以大大降低接收机的复杂度,特别适合于蜂窝移动通信系统的下行链路,因此在最近几年受到了国内外研究人员的广泛关注。
• The source and the arrangement of this thesis are provided . in chapter two , we introduce the mimo technology and its applications in the downlink of b3g system . we then discuss in detail the mmse sic detection algorithm
  第二章简要介绍了mimo技术框架以及该技术在b3g下行链路中的应用,接下来重点介绍了mmsesic检测算法,通过复杂度分析来说明硬件实现的困难所在。
• Hsdpa is written in release5 to increase transmit speed in certain time . as researchers found that the amount of data between downlink and uplink is unequal , and the former one has a larger amount than the latter one
  针对3g系统中不对称的上下行传输,下行链路业务量普遍大于上行链路业务量这一典型特征, 3gpp在release5协议版本中提出了hsdpa概念,旨在提高某一时刻的传输速率。
• Hence , in this paper , we present some research wok in the three topics mentioned above : in the topic of distributed mimo detection , we propose a coherent receiver model for distributed mimo systems to solve the asynchronous reception problem in the downlink
  本文拟在上述三个方面做一些工作:本文针对分布mimo系统的下行链路中,发射信号异步到达接收机的问题,提出了一种分布mimo相干接收机模型。
• At short microwave and long millimeter wave bands , the ratios of the rain - induced attenuation on up - link to down - link are estimated on earth - space slant paths . a comparison of the prediction results with the experiment data in boston and kashima areas is carried out
  在微波和毫米波低端，预测了地一空路径上、下行链路雨衰减的比率，并与美国波士顿和日本kashima地区的实验数据进行了比较，结果一致性较好。
• It is particulary suited to multirate signal transmission due to the use of an offset stacked spreading modulation scheme , which simplifies th ' e rate - matching algorithm relevant to multimedia services and facilitates asymmetric traffic in up - and downlink transmissions for ip - based applications
  通过调整偏移栈，偏移的大小，可简化多媒体服务的速率匹配算法，特别适用于ip网络中上行链路和下行链路非对称业务的传送。
• 2 . with the principles of statistical signal processing theory and density function estimating theory , the minimum bit error rate ( mber ) mud and the least bit error rate ( lber ) mud using optimum designing methods under synchronous ds - cdma downlink are studied . 3
  以统计信号处理理论和密度函数估计理论为基础，利用最优化设计方法在同步ds - cdma系统的下行链路研究了最小误码率多用户检测器及自适应实现的lber多用户检测器。