CDMA数字无绳用户交换系统

本文介绍一种基于ＣＤＭＡ技术的数字无绳用房交换系统。首先阐述了该系统的组成和功能,而后概要说明系统的工作原理。最后作者阐明该民无线本地环路系统间在原理上的互通性。     

基于无线电台的电话延伸系统

现阶段在我军的边防部队装备有大量旧式模拟制无线电台,这些电台的信号质量较差,接口功能有限,无法满足部队对通信的要求。本系统通过研制扩展接口设备,将电话网通过无线电台延伸到值勤巡逻分队,使指挥员可通过电话与一线外出分队直接通信。通过使用PIC18F8720微处理器和DSP芯片实现了这个接口设备,从试验仿真和结果来看,达到了研制目的,并且研制出了样机交付部队使用。     

Broadband Switching System Architecture

The architecture, the design concept, and the network organization for NTT's broadband switching system field trials are described. The features of this system are: a variety of connection-type services such as reservation-based and asymmetric connections, the installation of small-size remote concentrating switch, and a system integration using various subscriber transmission media such as optical fiber, satellite, and radio. This paper also presents the system architecture along with a study of the broadband switching system through a close look at the results obtained from field trials.     

LED显示屏云终端体系架构探索与应用

随着信息化时代的快速发展,公共信息发布在社会发展过程中已经扮演着越来越重要的角色。本文提出一种基于WebService开放性接口的LED云终端系统架构模式,该模式可以最大化地对现有资源进行整合．有利于建立一套基于标准开放性框架的终端显示体系。     

Application of Microprocessor to Cruise-Control System

A new cruise-control system incorporating a microprocessor has been developed. This system provides a preset speed function to preset a driving speed with a dial. Functions such as transmission control and fail-safe-against-abnormality have been realized.     

Switching Plan for a Cellular Mobile Telephone System

Federal Communication Commission Docket 18 262 allocated a 75-MHz band to the common carriers to implement high capacity mobile telephone systems. The Bell System has proposed a cellular arrangement of low-power transmitters/receivers that permits frequency reuse in a coverage area. This method of achieving spectrum efficiency will require extensive centralized coordination and control to properly administer channel assignments and to interconnect the mobiles with each other and with the direct distance dialing (DDD) network. This can be accomplished by means of an electronic switching system (ESS) with special data terminals and trunking arrangements, and a unique program. In the proposed plan the radio sites (base stations) act effectively as remote concentrators in the frequency domain under the control of ESS, which in turn acts primarily as a trunk-to-trunk switcher. In addition to the usual switching, signaling, and supervising functions, the switching office must also perform numerous special functions including paging of mobiles, location of mobiles (signal strength and ranging data analysis), channel reassignment of mobiles, and reswitching of mobiles to various base stations-these last three occurring while customers are talking.     

Application of Microprocessor to Fuel Measurement System

A microprocessor can be used with a balance, weight set, and beaker to provide an economical and accurate measure of engine fuel consumption rate. The microprocessor controls the mechanical hardware, performs calculations, communicates with peripheral devices, and accepts calibration values. In this paper an integrating mass flow sensor and display system, which has been developed, is described. It uses an Intel microprocessor linked to a mechanical balance beam scale. It currently has capabilities to measure mass flow over a 2-to 100- kg/h range with a typical total long-term inaccuracy of no more than ± 0.2 percent of reading. It can also receive engine power output data and calculate normalized brake specific fuel consumption (bsfc), g/kWh. Integration time, flow rate, and bsfc are displayed on the front panel and are made available to peripheral devices using an EIA standard RS232C format.     

3G移动可视电话系统设计

介绍了3G移动可视电话的设计架构模式,基于Window CE操作系统,结合VTApp、3G-324M协议栈、音视频设备驱动、RIL和双端口RAM等相关模块,实现了可视电话这一复杂的多媒体应用系统的运行,描述了相关模块的工作原理与设计思路,并通过对呼出流程图加以介绍的方式,对可视电话系统的运行流程加以阐述。     

Microprocessor Utilization in Satellite-Born Packet Switching

This correspondence deals with the application of a bit slice microprocessor to a satellite born packet switch. A system architecture for accomplishing this task is proposed, and the performance of the packet switch is evaluated by obtaining an upper bound on the system throughput.     

Software Structure of No. 5 ESS--A Distributed Telephone Switching System

Most stored program controlled telephone switching systems are designed with centralized control architectures. Evolving processor technology and requirements of smooth growth over a wide size range have led system designers to take advantage of distributed processing architectures. This paper provides a conceptual framework for software partitioning on a distributed stored-program controlled switching system and discusses the resulting software structure as present in No. 5 ESS. To facilitate the software development process, a methodology based on current software engineering principles is employed. Sufficiently decoupled software components have expedited parallel development of software and provided reliability by reducing interaction and limiting propagation of errors among software components. The structuring strategy described for telephone switching is equally applicable to other distributed real-time control systems.     

异构网络终端接入智能切换系统研究

伴随着无线网络的迅速发展,智能终端日益普及。如何根据不同网络的通信速度、链路状态、通信费用以及不同类型业务流的特点等因素,在终端所接入的网络之间合理地切换则成为一个重要问题。提出了一种在Android系统下,通过对当前业务流流量特征的采集分析,同时结合当前各种网络的链路状态对接入网络实现合理切换的控制方法。最后使用Android手机与PC完成了系统搭建与测试,实现了基于流量信息合理选择接入网络的目的。     

分组交换网传送语音信息

本文先简单说明传统公用电话网的电路交换和数据通信网的分组交换原理。然后介绍语音压缩和分组语音技术在互联网和内部网上的应用 ,以实现互联网电话的新趋向。     

IP电话终端卡的试验研究

在对VoIP应用要求进行分析的基础上,介绍了一种IP电话终端卡的软硬件设计方案,详细介绍了硬件电路与软件编程方法,并作了局部仿真试验。该方案降低了成本,操作简便。     

用于县本地电话网的交换设备

本文介绍了用于县本地电话网交换设备的主要技术要求,给出了邮电部批准入网的此类设备的主要机型,并指出其发展趋势。     

Reliability Optimization in Telephone Switching Systems Design

In the design of telephone switching systems, the sequence of reliability design functions can be stated as 1) the formation of reliability objectives, 2) the allocation of these objectives, and 3) the modeling to verify the reliability obtained. Optimization techniques can be used in both reliability allocation and reliability modeling. This paper discusses the formation of reliability objectives and the methods of reliability goal allocation. Modeling examples are presented of a component-level reliability vs. cost trade-off and a system-level reliability analysis.     

互联网电视系统结构及终端关键技术分析

结合目前国内互联网电视的发展特点,从互联网电视系统的整体系统结构和终端两个方面进行讨论分析。在互联网电视端到端的整体架构的说明上,主要分析了从内容提供到终端显示的互联网电视系统层次结构,并重点讨论了互联网电视集成播控平台的功能。在针对互联网电视终端进行讨论时,重点分析了互联网电视终端操作系统、CPU以及音视频处理、互联网电视标准化四个方面的内容。     

单片机应用系统的抗干扰技术

以MSC-51系列的8031单片机为例，给出了在软硬件设计的不同阶段，对于不同干扰应采取的一些措施。     

IP电话终端的发展及设计

首先从技术角度介绍了IP电话的发展历程，接着介绍了国际电信联盟标准化组织ITU-T制定的IP电话的相关国际标准H.323建议，以及以G723.1语音压缩编码算法为代表的IP电话终端的关键技术。在此基础上，提出了一种以英特尔公司的8051单片微控制器和Analog Device公司的ADSP-2181数字信号处理芯片为核心的IP电话终端的设计方案。最后对IP电话的发展进行展望和预测。     

TACS制AXE─10移动电话交换系统对“并机”的侦测、跟踪与防治

ＴＡＣＳ制ＡＸＥ─１０移动电话交换系统对“并机”的侦测、跟踪与防治黄伟湘Ｔｒａｃｋｉｎｇｏｆｔｈｅ＂Ｃｌｏｎｅｓ＂ｉｎＡＸＥ－１０ＭｏｂｉｌｅＴｅｌｅｐｈｏｎｅＳｗｉｔｃｈｉｎｇＳｙｓｔｅｍ￥ｂｙＨｕａｎｇＷｅｉｘｉａｎｇ１概述随着我国经济的高速发展...     

关于天津电话交换网规划中涉及的几个问题

结合天津电信“十五”规划的编制，阐述了在新时期本地电话交换网规划中所涉及的几个问题，如电信网面临的形势和规划中需要解决的重大课题、电话业务持续发展的问题及由窄带网向宽带网过渡的问题等等。