公开(公告)号：US4907221A

公开(公告)日：1990-03-06

申请号：US192377

申请日：1988-05-10

申请人： Angelo Pariani ,  Francesco Natali

发明人： Angelo Pariani ,  Francesco Natali

IPC分类号： H04M3/56

CPC分类号： H04M3/561 ,  H04M3/002

摘要： A method of attenuating the echo signal in so-called telephone fork converting circuits, adapted for telephone conferences with a plurality of participants, consists of switching and arranging sequentially on a serial line messages from each participant as coded in the PCM code, by means of a digital switching array, and of performing a sign reversal on the PCM codings of a number of messages equal to the approximation to the nearest number below the number of participants in the conference divided by two. In the instance of an odd number of participants, first and second conferences are set up by means of a conference actuator, each conference comprising a different combination of inverted-sign coded messages and remaining coded messages from the participants, with consequent cancellation of the echo components having opposite sign; subsequently, on the double-wire receiving line associated with the telephone fork of each participant, one of said conferences is transmitted as deprived of the message related to that participant including a number of inverted-sign messages equal to that of the remaining original messages.

公开(公告)号：USRE35582E

公开(公告)日：1997-08-12

申请号：US606870

申请日：1996-02-26

申请人： Angelo Pariani ,  Walter Rossi ,  Vanni Saviotti

发明人： Angelo Pariani ,  Walter Rossi ,  Vanni Saviotti

IPC分类号： H04M19/00 ,  H04M1/00

CPC分类号： H04M19/005

摘要： A method of lowering the power absorbed by an interface circuit, in the "power-down" state thereof, as incorporated to a telephone exchange and connected to a telephone subscriber line, being of a type which comprises a monitoring circuit portion connected between the line and the exchange. The method involves the steps of,detecting the polarization level of a conductor in the line,comparing that level with a reference value by means of a comparator having an input connected to the line and an output connected to the input of the monitoring circuit portion,switching the interface circuit to a standby state on a higher level than the reference value being sensed,once again detecting the polarization level of the line, this time through the interface circuit, andactivating the telephone exchange when, on completion of the second detection step, the polarization level stays above the reference value.

摘要翻译： 一种降低由接口电路吸收的功率的方法，其在其“断电”状态下，并入电话交换机并连接到电话用户线路，其类型包括连接在线路之间的监视电路部分 和交流。 该方法包括以下步骤：检测线路中的导体的极化电平，通过具有连接到该线路的输入的比较器和连接到监视电路部分的输入端的输出端将该电平与基准值进行比较， 将接口电路切换到比所感测的参考值更高的待机状态，再次通过接口电路检测线路的极化电平，并且在第二检测步骤完成时激活电话交换机 ，极化水平保持高于参考值。

公开(公告)号：US5046089A

公开(公告)日：1991-09-03

申请号：US422892

申请日：1989-10-18

申请人： Angelo Pariani ,  Walter Rossi ,  Vanni Saviotti

发明人： Angelo Pariani ,  Walter Rossi ,  Vanni Saviotti

IPC分类号： H04M19/00

CPC分类号： H04M19/005

摘要： A method of lowering the power absorbed by an interface circuit, in the "power-down" state thereof, as incorporated to a telephone exchange and connected to a telephone subscriber line, being of a type which comprises a monitoring circuit portion connected between the line and the exchange. The method involves the steps of,detecting the polarization level of a conductor in the line,comparing that level with a reference value by means of a comparator having an input connected to the line and an output connected to the input of the monitoring circuit portion,switching the interface circuit to a standby state on a higher level than the reference value being sensed,once again detecting the polarization level of the line, this time through the interface circuit, andactivating the telephone exchange when, on completion of the second detection step, the polarization level stays above the reference value.

摘要翻译： 一种降低由接合电路（2）吸收的功率的方法，其在“断电”状态下，并入电话交换机（4）并连接到电话用户线路（3），其类型是 包括连接在线路与交换机之间的监控电路部分（6），包括以下步骤：检测线路（3）中的至少一个导体（9）的极化电平，将所述电平与参考值（VR）进行比较， 通过具有连接到线路（3）的输入的比较器（11）和连接到监视电路部分（6）的输入端的输出（U），将接口电路（2）切换到等待状态 高于所检测的参考值（VR），再次通过接口电路（2）检测线路（3）的极化电平，并激活电话交换机（4），其中在第二检测步骤完成时， 极化电平保持在参考值（VR）以上。