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农村数字交换机 英国GEC公司展出一组UXD5数字交换机,这种交换机可与2GHz8Mb/S微波无线电设备装在同一机架上,构成一个经济独立的数字通信系统。适合农村或城市郊区使用,为这些电话用户密度不大的地区经济而有效的提供先进的通信设施。60路转换复用器 英国标准电话电缆公司(STC)展出的60路转换复用器可以在一个FDM超群60路及其相关的信令信号与2个PCM30路2048Mb/S信号之间互相转换,不需要去复用至各个话路再进行转换。FDM部分也包括导频恢复与调节,所有载频供给都由设备内部产生,而且可以与外接频率标准同步。数字用户载波系统 NEC的DSC—30B数字用户载波系统可以为农村或边远地区用户经济有效的提供各种通信服务。采用多点上下话路技术,本系统利用一条2048Mb/S的线路可以连接最多4个远端站,接入最大用户数为30。本系统可以直接接入交换机,也可按上专用设备对用户线路进行测试。
Rural Digital Switch GEC UK debuted a group of UXD5 digital switches that can be housed in the same rack as 2GHz8Mb / S microwave radios to form an economy-independent digital communications system. Suitable for use in rural or suburban areas, providing advanced communications facilities economically and efficiently for these less densely populated areas. 60-Way Conversion Mux The 60-channel conversion multiplexer from STC is capable of interchanging between one FDM Super 60 and its associated signaling and two PCM30 2048 Mbit / s signals , Do not need to be reused to the various conversations and then conversion. The FDM section also includes pilot recovery and conditioning. All carrier frequency supplies are generated internally by the device and can be synchronized with external frequency standards. Digital Subscriber Carrier System NEC’s DSC-30B Digital Subscriber Line System provides cost-effective communication services for users in rural or remote areas. The use of multi-point up and down road technology, the system uses a 2048Mb / S line can connect up to 4 remote stations, the maximum number of users access to 30. The system can directly access the switch, you can press the dedicated equipment on the user line test.