公开(公告)号：US4292478A

公开(公告)日：1981-09-29

申请号：US42530

申请日：1979-05-25

申请人： John C. H. Davis ,  Krishnaswamy Natarajan

发明人： John C. H. Davis ,  Krishnaswamy Natarajan

IPC分类号： H04M19/00 ,  H04B1/58

CPC分类号： H04M19/001

摘要： Interface circuitry is provided between a pair of lines, on the one hand, and an input to and output from other equipment on the other hand. The interface circuitry will commonly be used between `tip` and `ring` lines of a telephone connection and office telephone equipment but is not limited to the telephone art. The interface equipment provides independently controllable and adjustable impedances to `longitudinal` and transverse voltage changes on the pair of lines, means for transferring signals from the pair of lines to the output line and means for transferring signals from the input line to the pair of lines.

摘要翻译： 另一方面，一方面在一对线路之间提供接口电路，另一方面提供输入到另一个设备的输入端。 接口电路通常用于电话连接和办公室电话设备的“提示”和“环”行之间，但不限于电话技术。 接口设备为一对线路上的“纵向”和横向电压变化提供独立可控和可调节的阻抗，用于将信号从一对线路传送到输出线路的装置以及用于将信号从输入线路传输到该对线路的装置 。

公开(公告)号：US4211895A

公开(公告)日：1980-07-08

申请号：US857744

申请日：1977-12-05

申请人： John C. H. Davis ,  Krishnaswamy Natarajan ,  Jan Cihal ,  Motek Szpindel ,  Jeffrey Sidwell

发明人： John C. H. Davis ,  Krishnaswamy Natarajan ,  Jan Cihal ,  Motek Szpindel ,  Jeffrey Sidwell

IPC分类号： H04Q3/52 ,  H04Q1/30 ,  H04Q3/56

CPC分类号： H04Q3/521

摘要： An electronic telephone system has a plurality of extensions connected radially to a central equipment by respective cables each providing separate speech and signalling paths. Each of the signalling paths is provided by a balanced conductor pair terminated by a matching impedance at the extension unit. The conductor pairs are connected to a common control unit at the central equipment, which scans the extensions in a time-division multiplex mode, signalling data being transmitted over the conductor pair from the addressed extension to the control unit in a first period of the time slot allotted to the extension, and signalling data being transmitted from the control unit to the addressed extension in a second period of the allotted time slot. The system is also served by a number of trunks, which are scanned by the common control unit, the trunks being interfaced with the central equipment by interface units which include protective circuitry and logic control circuits.

摘要翻译： 电子电话系统具有多个通过相应电缆径向连接到中央设备的延伸部，每个电缆提供单独的语音和信令路径。 每个信令路径由在扩展单元处由匹配阻抗终止的平衡导线对提供。 导体对连接到中央设备的公共控制单元，其以时分多路复用模式扫描扩展，在第一时间段内通过导体对将信令数据从寻址的分机发送到控制单元 分配给扩展的时隙，以及在所分配的时隙的第二周期中从控制单元发送到寻址的分机的信令数据。 该系统还由多个中继线服务，这些中继线由公共控制单元扫描，中继线通过包括保护电路和逻辑控制电路的接口单元与中央设备接口。