M38 数字通信设备 标准查询与下载

ITU-T G.761-1993 60路编码转换设备的一般特性

The 60-channel transcoder implements a conversion between two 30-channel 2048 kbit/s PCM streams and one 60-channel 2048 kbit/s ADPCM stream. In the 30-channel 2048 kbit/s streams, the telephone signals are coded using 64 kbit/s A-law PCM as specified in Recommendation G.711.

GENERAL CHARACTERISTICS OF A 60-CHANNEL TRANSCODER EQUIPMENT

ITU-T G.761 FRENCH-1993 60路编码转换设备的一般性质

The 60-channel transcoder implements a conversion between two 30-channel 2048 kbit/s PCM streams and one 60-channel 2048 kbit/s ADPCM stream. In the 30-channel 2048 kbit/s streams, the telephone signals are coded using 64 kbit/s A-law PCM as specified in Recommendation G.711. In the 60-channel 2048 kbit/s stream, the telephone signals are coded using 32 kbit/s ADPCM as specified in Recommendation G.721. Figure 1/G.761 indicates the nomenclature used for the three different signal ports A, B and C.

GENERAL CHARACTERISTICS OF A 60-CHANNEL TRANSCODER EQUIPMENT

ITU-T G.762-1993 48路编码转换设备的一般特性

The 48-channel transcoder provides for the conversion between two 24-channel 1544 kbit/s PCM streams and one 48-channel 1544 kbit/s ADPCM stream. In the 24-channel 1544 kbit/s streams, the voice-frequency signals are coded at 64 kbit/s according to the PCM μ-law defined in Recommendation G.711.

GENERAL CHARACTERISTICS OF A 48-CHANNEL TRANSCODER EQUIPMENT

ITU-T G.762 FRENCH-1993 48路编码转换设备的一般性质

The 48-channel transcoder provides for the conversion between two 24-channel 1544 kbit/s PCM streams and one 48-channel 1544 kbit/s ADPCM stream. In the 24-channel 1544 kbit/s streams, the voice-frequency signals are coded at 64 kbit/s according to the PCM µ-law defined in Recommendation G.711. In the 48-channel 1544 kbit/s stream, the voicefrequency signals are coded at 32 kbit/s according to the ADPCM encoding law defined in Recommendation G.721.

GENERAL CHARACTERISTICS OF A 48-CHANNEL TRANSCODER EQUIPMENT

ITU-T G.702-1993 数字系列比特率

digital hierarchy bit rates are those bit rates which are or will be used as the basis for higher digital hierarchy levels if such levels exist (see Recommendation G.701, definition 4003)

DIGITAL HIERARCHY BIT RATES

ITU-T G.724-1993 工作在1544kbit/s的48路低比特率编码基群复用设备的特性

The 48-channel primary multiplexer provides conversion between 48 voice-frequency channels and one 1544 kbit/s ADPCM stream. In the 1544 kbit/s stream, the voice-frequency signals are coded according to the PCM encoding law defined in Recommendation G.711 and the ADPCM encoding law defined in Recommendation G.721.

CHARACTERISTICS OF A 48-CHANNEL LOW BIT RATE ENCODING PRIMARY MULTIPLEX OPERATING AT 1544 kbit/s

ITU-T G.725-1993 使用64kbit/s内的7kHz音频编解码器的系统方面

This Recommendation should be associated with Recommendation G.722 7 kHz audio coding within 64 kbit/s and Recommendation H.221 Frame structure for a 64 kbit/s channel in audiovisual teleservi

SYSTEM ASPECTS FOR THE USE OF THE 7 kHz AUDIO CODEC WITHIN 64 kbit/s

ITU-T G.731-1993 音频用基群脉冲编码调制(PCM)复用设备

pulse code modulation (PCM) multiplex equipments are already used in various countries, in particular to provide a large number of short-distance telephone circuits on certain pairs in existing cables, and in order to minimize the number of different PCM multiplex equipments providing circuits which may be used in international connections,

PRIMARY PCM MULTIPLEX EQUIPMENT FOR VOICE FREQUENCIES

ITU-T G.732-1993 工作在2048kbit/s的基群脉冲编码调制(PCM)复用设备的特性

The encoding law used is the A-law as specified in Recommendation G.711. The sampling rate, load capacity and the code are also specified in that Recommendation.

CHARACTERISTICS OF PRIMARY PCM MULTIPLEX EQUIPMENT OPERATING AT 2048 kbit/s

ITU-T G.733-1993 工作在1544kbit/s的基群脉冲编码调制(PCM)复用设备的特性

The encoding law used is the μ-law as specified in Recommendation G.711. The sampling rate, load capacity and the code are also specified in that Recommendation.

CHARACTERISTICS OF PRIMARY PCM MULTIPLEX EQUIPMENT OPERATING AT 1544 kbit/s

ITU-T G.745 SPANISH-1993 工作在6312 kbit/s并采用正/零/负码速调整的二阶多路复用设备

The second order digital multiplex equipment using positive/zero/negative justification, considered below, is intended for use on digital paths between countries using 2048 kbit/s primary multiplex equipments, such as the PCM multiplex equipment described in Recommendation G.732 or any identical equipment.

SECOND ORDER DIGITAL MULTIPLEX EQUIPMENT OPERATING AT 8448 kbit/s AND USING POSITIVE/ZERO/NEGATIVE JUSTIFICATION

ITU-T G.755-1993 工作在139264kbit/s并复接三个44736kbit/s支路的数字复用设备

The digital multiplex equipment described in this Recommendation is intended for use between networks using different digital hierarchies as specified in Recommendations G.702 and G.802.

DIGITAL MULTIPLEX EQUIPMENT OPERATING AT 139 264 KBIT/S AND MULTIPLEXING THREE TRIBUTARIES AT 44 736 KBIT/S

ITU-R SF.1004-1993 与固定业务共享频段的固定卫星业务地球站水平方向发射的最大等效各向同性辐射功率

Definitive limits applicable in shared frequency bands are laid down in Article 28 of the Radio Regulations (RR) (Nos. 2540 to 2548.1).

Maximum Equivalent Isotropically Radiated Power Transmitted Towards the Horizon by Earth Stations of the Fixed-Satellite Service Sharing Frequency Bands with the Fixed Service

ITU-T P.84-1993 评价数字电路倍增和分组化语音系统的主观收听测试方法

The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the International Telecommunication Union. The ITLJ-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to

Subjective Listening Test Method for Evaluating Digital Circuit Multiplication and Packetized Voice Systems - Telephone Transmission Quality Subjective Opinion Tests (Study Group XII) 22 pp

ITU-T Q.957-1993 (撤回)使用DSS 1数字标识补充业务的第3阶段描述:条款1:用户至用户信令(UUS)-NO.1数字用户信令系统

The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the International Telecommunication Union. The ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to

Stage 3 Description for Additional Information Information Transfer Supplementary Services Using DSS 1 Clause 1 - User-to-User Signalling (UUS) - Digital Subscriber Signalling System No. 1 - Stage 3 Description for Supp. Services Using DSS 1 (Study Group

ITU-T Q.955.1-1992 使用No.1数字用户信令系统(DSS1)的行业共用补充业务第3阶段描述:闭和用户群(CUG)

The supplementary service Closed User Group (CUG) enables users to form groups, to and from which access is restricted.A specific user may be a member of one or more CUGs.Members of a specific CUG can communicate among themselves but not,in general,with users outside the group. Specific CUG members can have additional capabilities that allow them to originate calls outside the group, and/or to receive calls from outside the group.Specific CUG members can have additional restrictions that prevent them from originating calls to other members of the CUG, or from receiving calls from other members of the CUG.

STAGE 3 DESCRIPTION FOR COMMUNITY OF INTEREST SUPPLEMENTARY SERVICES USING DSS 1 SECTION 1 - CLOSED USER GROUP

YD/T 521-1992 数字交换机模拟接口测试方法及模拟接口（二线或四线）间传输特性的测试方法

本标准规定了数字交换机模拟接门测试方法及模拟接口二线间或四线间传输特性测试的方法。 本标准适用于数字交换机鉴定、验收及维护测试。

Test method of digital exchange analog interfaces and test method of transmission characteristics between (2-wire or 4-wire) analog interfaces

ITU-T T.90 SPANISH-1992 综合业务数字网(ISDN)中终端和信息通信业务的特点和协议.信息通信业务的终端设备和协议.修改件1;修改件2;13号研究组;105pp

This Recommendation defines the functional profile for base standards ISO/IEC 7776, 8208 and 8885 to provide the lower layers of the telematic services protocol stack when operating on the ISDN. Parameter values are recommended to ensure good throughput when operating via long delay connections such as satellite routes. Backward compatibility with the Blue Book version has been maintained. Three methods of negotiating the lower layer parameter values have been included to satisfy various connection scenarios, e.g. completely within the ISDN or between the ISDN and other digital networks. This Recommendation supplies the network layer definition in Recommendation T.70 for telematic terminals but not the transport layer definition which is still retained as the telematic transport layer definition.

CHARACTERISTICS AND PROTOCOLS FOR TERMINALS FOR TELEMATIC SERVICES IN ISDN

ITU-R BT.711-1 SPANISH-1992 数字分量演播室的同步参考信号

The CCIR considering a) that the definition of synchronizing reference signals for component digital studios would be of benefit in the implementation of equipment operating in accordance with Recommendations 601 and 656; b) that such signals should have a maximum of commonality between the 525 line and 625 line versions; c) that signals in accordance with Recommendation 656 contain in a conveniently accessible and accurate form all the information required to synchronize digital component equipment; d) that the use of digital circuitry introduces the possibility of new techniques in studio synchronization; e) that equipment in accordance with Recommendations 601 and 656 may have to operate in a mixed analogue and digital environment for a considerable period; f) that compatibility with synchronizing reference signals for component analogue studios would be an advantage; g) that signals generated in accordance with Recommendation 470 are widely used for synchronization in studios.

Synchronizing reference signals for the component digital studio

ITU-R BT.711-1 FRENCH-1992 数字分量演播室的同步参考信号

The CCIR considering a) that the definition of synchronizing reference signals for component digital studios would be of benefit in the implementation of equipment operating in accordance with Recommendations 601 and 656; b) that such signals should have a maximum of commonality between the 525 line and 625 line versions; c) that signals in accordance with Recommendation 656 contain in a conveniently accessible and accurate form all the information required to synchronize digital component equipment; d) that the use of digital circuitry introduces the possibility of new techniques in studio synchronization; e) that equipment in accordance with Recommendations 601 and 656 may have to operate in a mixed analogue and digital environment for a considerable period; f) that compatibility with synchronizing reference signals for component analogue studios would be an advantage; g) that signals generated in accordance with Recommendation 470 are widely used for synchronization in studios.

Synchronizing reference signals for the component digital studio