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公开(公告)号:JP2001077887A
公开(公告)日:2001-03-23
申请号:JP2000214303
申请日:2000-07-14
Applicant: LUCENT TECHNOLOGIES INC
Inventor: JONATHAN HERMAN FISHER , RENE A SMITH , MICHAEL G WILLIAMS
Abstract: PROBLEM TO BE SOLVED: To power up an electronic circuit from a telephone line without generating a lock-up state by applying the electric power of telephone lines to the electronic circuit according to the characteristics of the detected voltage between the telephone lines. SOLUTION: After the voltage level from a telephone office 16 rises to a voltage which is high enough for the accurate operation of an on-hook electronic circuit 18, the electric power of the telephone lines is only connected to the electronic circuit 18 to solve the trouble generated by the dynamic resistance and terminating resistance R1 of the electronic circuit 18. Concretely, a voltage detector 12 controls a switch 14. The buildup trip point of the voltage detector 12 is set to a point which guarantees a voltage VDD which is high enough for the accurate operation of the on-hook electronic circuit 18. When the voltage detector 12 trips, a reset signal turns on the switch 14 and the electric power of the telephone lines is supplied to the electronic circuit 18 at the voltage level guaranteeing the accurate operation of the on-hook electric circuit.
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公开(公告)号:JP2001177447A
公开(公告)日:2001-06-29
申请号:JP2000289844
申请日:2000-09-25
Applicant: LUCENT TECHNOLOGIES INC
Inventor: PAUL DAVID HENDRICKS , DONALD RAYMOND RATORERU , RENE A SMITH , STEVEN BROOKE WITTMER
Abstract: PROBLEM TO BE SOLVED: To provide a configuration/method by which the dynamic range of a transmitted signal can be made flat so as to minimize return loss. SOLUTION: The above task can be solved by providing a digital pre- distorted filter in a data access device DAA in a MODEM chip set. Placing the pre-distorted filter at the outside of the DAA attains digital processing such as digital emulation of the impedance of a central station, thereby avoiding the effect by giving pre-distortion to a transmission signal. In the case of a digital emulation filter, placing the pre-distorted filter to the outside of an (A/D) loop/(D/A) loop can minimize noise.
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公开(公告)号:JP2001186270A
公开(公告)日:2001-07-06
申请号:JP2000309803
申请日:2000-10-10
Applicant: LUCENT TECHNOLOGIES INC
Inventor: JONATHAN HERMAN FISHER , HOLLENBACH KEITH EUGENE , DONALD RAYMOND RATORERU , RENE A SMITH , TOTH MICHAEL S , ZHU WEILIN
Abstract: PROBLEM TO BE SOLVED: To provide an inexpensive and reliable digital access arrangement(DAA) which can be fed with power at least partially by an available line current provided by various countries. SOLUTION: This DAA adaptively enables an operation that is suitable as a condition guarantee by power supplied from the telephone line and meanwhile, satisfies relevant required conditions of many countries. In a line powered codec, a startup procedure for an international line powered codec uses register setting, for instance, register setting of a specified country, and the register setting is fed with power from the low voltage side (e.g. a PC or modem side) of the line powered codec and maintained. Thus, a state in which the line powered codec is programmed can be maintained even during a low line power state, so the line powered codec does not always return to a default state by resetting due to a power loss in the telephone line.
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公开(公告)号:JP2001203804A
公开(公告)日:2001-07-27
申请号:JP2000309804
申请日:2000-10-10
Applicant: LUCENT TECHNOLOGIES INC
Inventor: JONATHAN HERMAN FISHER , DONALD RAYMOND RATORERU , RENE A SMITH , TOTH MICHAEL S , MICHAEL G WILLIAMS
Abstract: PROBLEM TO BE SOLVED: To provide an inexpensive and reliable digital access arrangement(DAA), with which power can be partially supplied at least by available line currents provide by various countries. SOLUTION: This DAA adaptively enables operation suitable as the condition guarantee with power supplied from a telephone line, which it satisfies requested conditions related to a number of countries. Concerning a line power codec, register setting such as register setting for specified country, for example, is used for a startup procedure for an international line powered codec, and this is supplied and held with power from the low-voltage side (for example PC or modem side) of the line powered codec. Thus, the programmed state of the line powered codec can be kept even during the low line power state. Therefore, the line powered codec is not always returned into default state by reset caused by power loss within a telephone circuit.
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公开(公告)号:JP2001103126A
公开(公告)日:2001-04-13
申请号:JP2000249208
申请日:2000-08-21
Applicant: LUCENT TECHNOLOGIES INC
Inventor: JONATHAN HELLMAN FISHER , LATURELL DONALD R , RENE A SMITH , STEVEN BURUUKU WITTOMAA
Abstract: PROBLEM TO BE SOLVED: To eliminate the occurrence of an error due to a DC offset in an analog circuit caused when a DC line current of a telephone line is adjusted. SOLUTION: The method and the system are to adjust a DC line current in a telephone line and to reduce the quantity of errors introduced to a system. Compensating a DC error component introduced by an A/D converter having a DC offset can reduce the error. A software program can limit the DC error according to predetermined parameters through digital control of the DC offset. The predetermined parameters are selected to cover specifications in various countries in place of a switch controlling resistors and capacitors. Furthermore, even when a standard of a country is changed, the software program can cope with the change in place of replacing components or redesigning a printed circuit board.
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