共查询到20条相似文献,搜索用时 250 毫秒
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TD-SCDMA系统OTDOA-IPDL定位方法 总被引:1,自引:0,他引:1
对TD-SCDMA系统中的多基站定位方法进行了研究,提出了一种利用TD-SCDMA物理层帧结构中的下行同步序列进行定位的OTDOA-IPDL定位方法。该方法针对OTDOA定位方法中移动终端不能够准确地检测到非服务基站的信号,提出基于TD-SCDMA系统的IPDL技术,保证移动终端能够准确检测到非服务基站发送的下行同步信号,提高定位精度。在此重点描述了TD-SCDMA系统中的IPDL技术,并通过仿真验证所提方法的定位性能,说明IPDL技术在多基站定位中的重要性。 相似文献
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地面终端站KSA(Ka-band Single Access)高速卫星数据传输接收系统基带数据的处理既要实现基带数据记录存储、实时转发和事后按可控制的帧频转发等业务,又要满足返向高速基带输出的处理时延不大于40 ms实时性需求。针对基带数据的处理业务多样性和实时性之间的矛盾,提出了一种基于CPCI(Compact Peripheral Component Interconnect)结构且满足基带数据的处理应用业务多样性和高实时性的处理架构,实现了一种高速卫星信号基带数据实时处理平台。经搭建测试平台并拷机500 h,该架构下的处理平台能够稳定地实时处理600 Mb/s卫星基带数据的所有业务类型,并在地面终端站KSA卫星信号数据传输系统中得到了工程实践验证。 相似文献
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介绍了一种新型PHS基站信号再生设备的设计与实现方法,完成了该系统的硬件模块设计和软件设计及编译,并对软件流程进行了详细的介绍。该系统主要采用小灵通基带芯片ML7338(ARM7TDMI核)和RDA5206射频模块,实现对射频信号的解调,同时对基带信号重新编码再调制发射,很好地解决了普通直放站射频干扰问题。所设计的信号再生设备能实现对PHS信号的变换与转发,能够有效解决当前小灵通网络的盲区问题。 相似文献
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The base station (BS) in the CDMA Mobile System (CMS) connects calls through the radio interface and is designed to provide mobile subscribers with high quality service in spite of mobile subscribers’ motions. The BS consists of multiple base station transceiver subsystems (BTSs), a base station controller (BSC) and a base station manager (BSM). This paper is concerned with the BSC and the BSM. The BSC is located between the BTSs and the mobile switching center (MSC) connected with the public network, and is responsible for controlling mobile calls from and to mobile subscribers via the BTSs. The BSM provides operator-interfaces per the BS and takes responsibility of operation and maintenance (OAM) of the BS. Design of the BSC is based on two module types: functional module and unit module. The functional module is used to support new services easily and the unit module to increase the system capacity economically. Both modular types are easily achieved by inserting the corresponding modules to the system. Particularly, in order to efficiently support the soft handover which is one of CDMA superior advantages, the BSC adopts a large high-speed packet switch connecting up to 512 BTSs, and thus mobile subscribers can be provided with soft handover in high probability. The BSM is based on a commercial workstation to support OAM functions efficiently and guarantee high reliability of the functions. The BSM uses graphical user interface (GUI) for efficient OAM functions of the BS. 相似文献
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《Vehicular Technology, IEEE Transactions on》1978,27(4):205-211
The 800-MHz band land mobile telephone system which is going into service in Tokyo and other major cities is described. This system is characterized by 1) an ordered array of cells which allows each radio channel to be reused by spacing at an appropriate coordination distance in a wide service area (cellular system), 2) development of a new higher frequency band, and 3) a fully automatic exchange system integrated with the ordinary telephone network. Field tests have been carried out in the Tokyo metropolitan area since 1975 and have now been brought to a successful completion. 相似文献
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Design of a tunnel relay system with a leaky coaxial cable in an 800-MHz band land mobile telephone system 总被引:1,自引:0,他引:1
《Vehicular Technology, IEEE Transactions on》1980,29(3):305-316
System design of a tunnel relay system in an 800-MHz band land mobile telephone system is described. Several dozen RF signals from a base station or many different mobile units in the tunnel are directly amplified in the RF stage, without frequency conversion, by a common amplifier in the relay equipment installed near the tunnel entrance, then radiated into the tunnel through a leaky coaxial cable (LCX) or to the base station by a unidirectional antenna. Repeaters are inserted along the LCX to compensate for transmission loss in RF signal power inside the cable. Amplifying a number of RF signals simultaneously, a common amplifier generates intermodulation products and radiates spurious signals. The required amplifier linearity to suppress the spurious signals is discussed in detail. The combination of LCX and service area in the tunnel is determined according to the amplifier performance, the number of radio channels assigned to the base station, and the radio wave propagation characteristics in the tunnel. 相似文献
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家庭智能化网络监控系统的设计 总被引:1,自引:0,他引:1
针对目前家庭住宅人身财产的安全,设计了一种基于单片机为控制核心,通过全球移动通信系统(GSM,Global System For Mobile Communications)无线移动网络与公用电话网络,实现远程自动监控报警控制的系统。该设计是以GSM移动网络与公用电话网络为媒介,通过手机用户、电话用户实现对远程住宅设备的控制及信息采集。重点阐述了GSM模块、双音多频(DTMF,Dual Tone Multi Frequency)检测发生模块的硬件设计原理及应用。介绍了MT8880芯片与GSM模块的连接及实现原理。实际应用说明了该设计系统稳定、可靠、成本低廉。 相似文献
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当前的移动通信网络,通常由操作维护中心(OMC)、基站控制器(BSC)、基站(BS)和终端用户(UE)四级网元组成。BSC和BS通常称为基站子系统(BSS)。OMC通常由大型的工作站组成,是无线网络的管理核心,它对BSC进行直接的控制和管理。当BSC或BS添加一些新的功能或软硬件升级时,首先要做的是评估新增加的功能对OMC造成的影响。这些影响包括对CPU利用率、存储器(memory)利用率和数据库(database)利用率的影响。在实际测试数据的基础上,提出了OMC CPU利用率的估算方法。利用所提出的估算方法,可以方便地估算其他网元新增加的功能对OMC CPU所造成的影响。 相似文献
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本文从大都市移动电话网的现状出发,分析了移动电话发展的趋势,针对大都市移动电话的发展特点,对移动网的网结构和组网方案,基站和无线接入网的建设等方面进行了探讨。 相似文献
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介绍了双模式码分多址移动通信系统的概念和用途,它的网络结构和公众电话交换网的连接、频带配置、容量计算和提高容量措施以及所提供的业务。 相似文献
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AVirtualPrivateLocalPCNRingNetworkBasedonATMVPCross-ConnectionLiuBin;MaYingjun;MengLuoming(BeijingUniversityofPostsandTelecom... 相似文献