M40 电话通信设备 标准查询与下载

ITU-R P.371-8-1999 长期电离层预测的指数选择

The concept of indices for long-term ionospheric predictions relies on the. assumption that the important characteristics of the ionosphere, such as the critical frequencies of the various layers and the MLTF factor M(3000)F2, depend in a systematic way o

Choice of Indices for Long-Term Ionospheric Predictions

ITU-R P.1058-2-1999 用于传播研究的数字拓扑数据库

Digital topographic databases established for the purpose of propagation predictions need to contain information which is related to the type of prediction being undertaken. For frequencies above about 30 MHz, information about the terrainheight and groun

Digital Topographic Databases for Propagation Studies

ITU-R OPINION 23-6-1999 电离层传播的基础指数的必要研究

that the Sunspot Index Data Centre (SIDC) sponsored by the Observatoire Royal de Belgique and the Federation of Astronomical and Geophysical Data Analysis Services (FAGS) be encouraged to continue determination and distribution of the international relat

Observations Needed to Provide Basic Indices for Ionospheric Propagation

ITU-R M.1036-1-1999 1885-2025MHz和2110-2200MHz频段IMT-2000实施的频谱考虑

International Mobile Telecomunications-2000 (IMT-2000) are third generation mobile systems which are scheduled to start service around the year 2000 subject to market considerations. They will provide access, by means of one or more radio links, to a wide

Spectrum Considerations for Implementation of International Mobile Telecommunications-2000 (IMT-2000) in the Bands 1 885-2 025 MHz and 2 110-2 200 MHz1

ITU-R M.1391-1999 IMT-2000地面频谱要求计算方法

International Mobile Telecommunications (IMT-2000) are third generation mobile systems which are scheduled to start service around the year 2000 subject to market considerations.

Methodology for the Calculation of IMT-2000 Satellite Spectrum Requirements

ITU-R M.1390-1999 IMT-2000地面频谱要求计算方法

IMT-2000 are third generation mobile systems which are scheduled to start service around the year 2000 subject to market considerations. They will provide access, by means of one or more radio links, to a wide range of telecommunication services supported

Methodology for the Calculation of IMT-2000 Terrestrial Spectrum Requirements

ITU-R BR.1422-1999 对于具有噪声减少和矩阵环绕声影片声轨迹编码的电视使用的操作实践

that since television reception does not allow as high a dynamic range as the cinema, if any correction of dynamic range is necessary, it should be done after noise reduction expansion and applied simultaneously on both encoded channels.

Operational Practices for Television Use of Film Soundtracks Encoded with Noise Reduction and Matrix Surround

ITU-R BO.2019-1999 干涉计算方法

The role of the Radiocommunication Sector is to ensure the rational, equitable,efficient and economical use of the radio-frequency spectrum by all radiocommunication services, including satellite services and carry out studies without limit of frequency r

Interference Calculation Methods

ANSI/TIA/EIA 3700-1999 模拟调制解调器性能评估用电话网络传输模型

Defines a model of the characteristics of the Public Switched Telephone Network (PSTN) in the continental United States of America to be used to measure modem transmission performance. This standard was first listed for public review in the July 17, 1998 issue of Standards Action. It is being resubmitted due to substantive changes to the text.

Telephone Network Transmission Model for Evaluating Analog Modem Performance

YD/T 720-1998 电话机检验规程

本标准规定了GB/T 15279-1994《自动电话机技术条件》中有关试验的检验规程。 本标准适用于双音多频式和脉冲式按键电话机。

Test procedures for telephone sets

YD/T 992-1998 电话机附加功能的基本技术要求及检验方法

本标准规定了电话机附加功能的标注名称、技术要求及检验方法。 本标准可作为产品设计、生产及检验的依据。

Technical requirments and test methods of telephone additional functions

YD/T 928-1997 N-ISDN 第二类网络终端(NT2 型)设备ISDN 用户交换机技术规范

本标准主要规定窄带综合业务数字网(N-ISDN)中具有第二类网络终接功能(NT2)的ISDN自动用户交换机(ISPBX)的各项技术要求。 本规定适用于接入公用N-ISDN的各种ISPBX。以30B+D接口入网的其他具有NT2功能的设备，例如局域网设备、复用设备、路由器等人网基本技术要求需符合YDN 034 1997C(1SDN用户-网络接日技术规范的要求。

Technical specification for ISDN PABXs

BS 7378-3:1998 使用2号数字存取信号传输系统(DASS 2)经CCITT推荐标准G.703的2048千位/秒接口的公共电信系统连接装置.与信号传输系统相关的信道(CASS)连接装置要求

This part of BS 7378 specifies requirements for apparatus for connection to public telecommunications systems using channel associated signalling systems (CASS). These requirements apply to all such apparatus, irrespective of whether the apparatus provides additional interfaces, telecommunications services or functions. NOTE 1 "Connection to public telecommunications systems" means both direct connection to a network termination point (NTP) and indirect connection where interworking occurs by means of the applicable NTP via one or more items of intervening apparatus. The requirements made in this part of BS 7378 cover call set-up and clearing. They do not cover any supplementary services requirements that might exist. Requirements are specified in terms of apparatus performance at the interface at the apparatus terminations (see 4.1). The requirements are general design requirements intended to prevent interference with the PTOs' networks and with other users, but compliance is not intended to ensure full compatibility with CASS and will not necessarily ensure that the apparatus is satisfactory for the user's purpose. NOTE 2 In addition to the design requirements specified in this standard, the requirements of other product standards may apply depending on the function of the apparatus. NOTE 3 If the apparatus is to be connected to, or to interwork with, any service run by public telecommunications operators, it will have to meet the approval requirements applicable to that service. The requirements for the safety of the public telecommunications systems from electrical conditions originating in the connected apparatus are not specified in this standard.

Apparatus for connection to public telecommunications systems using the Digital Access Signalling System No. 2 (DASS 2) via a 2048 kbit/s CCITT Recommendation G.703 interface - Requirements for apparatus for connection to Channel Associated Signalling Sys

YD/T 978-1998 公用电话网数字排队机技术要求及测试方法

本标准规定了数字排队机接人公用电话网时必须统一遵循的技术条件，主要内容包括定义、容量系列、技术要求及检测方法。 本标准适用于数字排队机。主要应用于特种业务台。

Technical requirment and test method for digital queue equipment of PSTN

ITU-T SERIES A SUPP 1-1998 与建议相关协议质量方面的指导方针

In this Recommendation, the expression "Administration" is used for conciseness to indicate both a telecommunication administration and a recognized operating agency.

Guidelines on Quality Aspects of Protocol Related Recommendations - Series A: Organization of the Work of the ITU-T

ETSI TR 101 184-1998 双线模拟语音宽带接口.多线路终端设备的具体特性(版本1.1.1)

2-Wire Analogue Voice Band Interfaces; Multiple Line Terminal Equipment Specific Characteristics (V1.1.1)

ETSI TBR 8-1998 综合业务数字网(ISDN).3.1 kHz电话远程业务.手机终端的附加要求.第2版

Integrated Services Digital Network (ISDN); Telephony 3,1 kHz Teleservice; Attachment Requirements for Handset Terminals

ITU-T O.81 APP.1-1998 电话型电路用群延迟测量设备.附录1:电话型电路用振幅和相位的快速测量用测量信号(多频声试验信号)

The multitone test signal (MTTS) consists of a spectrum of N discrete signals separated by frequency spacing of 100 Hz in the low frequency range. The spectral lines are all of equal amplitude; their phase relationship to each other is chosen on the basis of mathematical considerations so that the energy of the test signal is distributed approximately evenly across the entire period of the test signal. The transmission characteristics, i.e. the amplitude and phase distortion of a telephone line, produce changes in the test signal. On the receive side, these changes are measured and evaluated, e.g. by means of a Fourier analysis. The results may be displayed on a screen in the form of an amplitude andor phase graph and also, for example, the group delay may be derived from this.

Group-Delay Measuring Equipment for Telephone-Type Circuits - Appendix I: A Measuring Signal (Multitone Test Signal) for Fast Measurement of Amplitude and Phase for Telephone Type Circuits - Series O: Specifications of Measuring Equipment - Equipment for

ETSI TR 101 149-1998 双线模拟语音带宽接口.终端设备传输语音信号.对于电平限制要求的测试仿真(版本1.1.1)

2-Wire Analogue Voice Band Interfaces; Terminal Equipment Transmitting Voice Signals; Test Simulation for Level Limitation Requirements (V1.1.1)

ETSI TBR 38-1998 公共交换电话网(PSTN).对终端设备并入在将其连入欧洲PSTN的模拟接口时能够支持其正常业务的模拟手机功能的附加要求

Public Switched Telephone Network (PSTN); Attachment Requirements for a Terminal Equipment Incorporating an Analogue Handset Function Capable of Supporting the Justified Case Service when Connected to the Analogue Interface of the PSTN in Europe