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Copyright of Journal of Shanghai University / Shanghai Daxue Xuebao is the property of Journal of Shanghai University (Natural Sciences) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

通信技术的快速发展及用户需求的日益增长,导致小区业务负载分布出现越来越不均衡的现象,针对此问题,提出一种适用于LTE（长期演进）系统的基于负载预分配的移动负载均衡算法。当小区过载时,利用层次分析法选择最优目标小区,然后根据目标小区负载情况预分配过载小区负载量,再通过可变步长调整小区独立偏置,转移过载小区用户,实现小区间负载均衡。研究结果表明,该算法提升了小区间负载均衡度,减少了系统切换次数,增强了用户体验。

无线信道是十分复杂的传输信道,具有时变特性和衰落特性,AMC（自适应调制和编码）技术因具有能够使通信系统与无线信道相适应的特性,而成为了3GPP（第三代合作伙伴计划）LTE（长期演进）系统的一项关键技术。文章针对LTE系统提出了一种AMC实现方案,并对该方案的性能进行了仿真测试。仿真结果表明,该AMC方案能够有效地提高系统吞吐量。

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the networks design and training programs setting of LTE mobile communication training platform in Chongqing University of Posts and Telecommunications, which belongs to the Mobile Communications and Network State-level Lab Center. Cooperating with other platforms of the lab, the platform consists of hardware, software, and teaching resource, then forms the next generation fusing information network training platform simulating telecom operators network, and provides full-fledged services. It has been widely used in the teaching and research, and expands the experimental efforts of the lab center in the other information colleges and universities. [ABSTRACT FROM AUTHOR]

HARQ（混合自动重传请求）技术能够很好地补偿无线移动信道时变和多径衰落对信号传输的影响,已成为LTE（长期演进）系统中不可缺少的一项关键技术。针对TD-LTE（时分双工的LTE）系统中的上下行HARQ过程,提出了一种在DSP（数字信号处理器）中的实现方案,通过在DSP中运行,验证了该方案的有效性和可行性。

首先对基于TD-LTE（时分-长期演进）系统的咬尾卷积编码进行速率匹配。在深入研究3GPP（第三代合作伙伴计划）协议中咬尾卷积编码速率匹配算法的基础上,基于TD-LTE无线综合测试系统,提出了一种利用DSP（数字信号处理）实现的快速实现方案,通过程序在软件CCS3.3中的运行结果,验证了该方案及优化策略的可行性及有效性。

文章描述了LTE（长期演进）系统的网络结构,在此基础上,设计出了PDN（分组数据网）连接建立过程中专有承载的建立。用SDL（规范描述语言）和TTCN（数表结合表示法）对专有承载建立的实现进行了测试仿真,生成专有承载建立成功的MSC（消息顺序图）,并将仿真结果与协议规范进行比较以验证符合程度。该测试过程已应用于LTE无线综合测试仪表的开发中。

调度是LTE（长期演进）系统中基站为用户分配资源的重要环节和关键技术。UE（用户终端）一般通过BSR（缓存状态报告）和SR（调度请求）获得无线资源。文章针对BSR和SR同时存在时造成资源浪费的问题,通过不同的参数设置设计了解决方案,并且提出了一种在半静态调度下判断触发BSR和SR的方法以及解决填充BSR和其他BSR冲突的方法,有效地提高了资源利用率和系统稳定性。

首先介绍目前无线通信中常用的3种调度算法。为了提高频谱利用率,通过仿真比较了3种常用调度算法对系统性能的影响,提出基于QoS（服务质量）业务的比例公平调度算法。该调度算法兼容了其他调度算法的优点。实验中对用户配置不同的QoS参数,从吞吐量的角度来验证不同配置的用户有不同的吞吐量,而且系统会优先保障最优用户的需求。该调度算法提高了系统的最大吞吐量,满足了用户调度的公平性,给用户提供了不同的业务服务,保障了用户的不同需求。

第三代合作伙伴计划（3GPP）长期演进（LTE）系统与上一代无线通信网络相比,在基站传输速率和小区容量上都有了极大的提高,相应地对网络无线资源管理功能也提出了更高的要求。文章探讨了无线资源管理中的一个重要方面:负载均衡的问题。首先分析了网络中小区可能发生过载的原因,并讨论了传统的基于小区切换的解决方法可能存在的风险。随后提出一种以缩小终端搜索范围、并能避免乒乓效应为特征的算法。仿真结果表明,该算法能够实现小区中无线资源的优化分布。

文章基于长期演进（LTE）系统的咬尾卷积码,通过对多种Viterbi译码算法的仿真比较,为时分长期演进（TD-LTE）测试系统选择了一种最优的Viterbi译码算法,并在TMS320C64x数字信号处理器（DSP）中实现了这种算法。提出了一些具体的软件优化策略和技巧,对加比选蝶形运算进行了大量简化。通过译码程序在CCS3.3中的运行结果,验证了该算法及优化策略和技巧的可行性和有效性。

随机接入是移动通信系统中终端（UE）与基站建立上行同步和连接的一个非常重要的过程。文章主要研究时分-长期演进（TD-LTE）上行随机接入技术的设计。考虑到基于竞争模式的随机接入过程适用的普遍性,文章从随机接入的应用场景和类型出发,重点讨论基于竞争模式下的随机接入过程,并详细地分析了随机接入过程中的具体流程及实现方案。

第三代合作伙伴计划（3GPP）长期演进（LTE）系统的同步信号包括主同步信号与辅同步信号,用于小区搜索。文章介绍了辅同步信号的生成过程,并根据定点数字信号处理器（DSP）的特点,提出了一种简单的实现方案,并利用MATLAB软件对其进行了验证。该方案已应用于LTE-时分双工（TDD）无线综合测试仪表的开发中。

为了解决传统调制编码方案（MCS）选择准则对于性能提高的有限性,文章提出了一种新的MCS选择准则,并将其应用到自适应调制编码（AMC）的长期演进（LTE）系统。新准则用加权后的信噪比（SNR）为AMC系统确定合适的MCS。仿真结果表明,当吞吐量为2.8 bit/symbol时,新准则能够比两步预测准则带来2 dB的好处。将新准则应用到AMC-LTE系统,不仅在保证误码率（BER）性能的情况下补偿了由于信道时变引起的性能下降,而且也最大化了系统吞吐量。

为了实现LTE（长期演进）系统中的基站内切换,文章从控制面和用户面信令流程的角度出发,提出了一种LTE系统中的基站内切换设计方案。通过基站内各模块的协同工作,可有效实现包含数据转发的基站内切换流程,确保切换过程中不丢包,实现平滑切换。将该方案应用于实际的测试中,进行了基站内切换的组网测试,并给出了实际的切换测试结果。

为了提高随机接入过程中前导检测的效率,文章提出一种基于频域检测的固定阈值算法,该算法在频域检测的基础上通过假设固定阈值来检测签名前导序列,与传统时域的检测算法相比,它降低了复杂度,而且在阈值的选取上更加简单。通过性能仿真证明了该算法在不同信道环境下都有良好的检测性能。

Copyright of Journal of Chongqing University of Posts & Telecommunications (Natural Science Edition) is the property of Chongqing University of Posts & Telecommunications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of Beijing Institute of Technology is the property of Beijing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Guangdong University of Technology is the property of Journal of Guangdong University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

文章基于LTE（长期演进）采用的截尾卷积码,介绍了截尾卷积码的循环维特比译码算法（CVA）和环绕维特比算法（WAVA）,并综合两种算法的优点,对现有算法做了改进,减小了译码计算的复杂度。仿真结果表明,同WAVA相比,改进算法可获得较好的效果,且计算量减小了1/4。