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公开(公告)号：CA2237826C
公开(公告)日：2002-12-10
申请号：CA2237826
申请日：1998-05-19
Applicant: LUCENT TECHNOLOGIES INC
Inventor： WEAVER CARL FRANCIS , MEYERS MARTIN HOWARD , TARRAF AHMED A
Abstract: Telecommunications processing is applied to a reference signal to generate a signal under test. A fidelity measure is generated characterizing the fidelity of t he signal under test relative to the reference signal. A control signal is generated from the fid elity measure, where the control signal is used as a feedback signal to adjust the telecomm unications processing. In one embodiment, the reference signal is a speech signal and t he signal under test is a decoded speech signal generated by encoding, transmitting, and dec oding the reference speech signal. The fidelity signal is an average mean opinion scor e (MOS) and the control signal is used to control the speech decoding processing. For exampl e, the speech decoding processing may involve a speech decoder followed by a post filter, and the control signal is the cut-off frequency of the post filter. Such an embodiment may b e applied to real-time speech processing to adjust the speech decoding processing in the receiver of a telecommunications system that includes a speech encoder in a transmitter an d a communications network. Intermittently, the transmitter encodes reference si gnals that are also known to the receiver. The receiver performs the processing of the pres ent invention to update its speech decoding processing to optimize speech quality.
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公开(公告)号：BR9903784A
公开(公告)日：2000-08-29
申请号：BR9903784
申请日：1999-08-19
Applicant: LUCENT TECHNOLOGIES INC
Inventor： TARRAF AHMED A
Abstract: A method for conveying information-carrying teletype signals over a wireless telecommunication system by encoding the information into a repetitive signal. Teletype information is derived from part of a received signal encoded as a repetitive signal which part has been determined not to have been adversely affected by the wireless telecommunication system.
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公开(公告)号：AU4475299A
公开(公告)日：2000-03-16
申请号：AU4475299
申请日：1999-08-26
Applicant: LUCENT TECHNOLOGIES INC
Inventor： HOFFBECK JOSEPH P , TRACY KEVIN G , TARRAF AHMED A , PREMJI AL-NASIR A , MEYERS MARTIN HOWARD
Abstract: It has been recognized that in a wireless communication system certain frames of encoded speech data transmitted between a base station and a mobile unit, or between a mobile unit and a base station, are more critical than others. A frame may be determined to be erased by the receiving base station or mobile unit due to noise or interference over the wireless transmission medium. If an erased frame cannot be recreated from one or more preceding frames, then it is more critical than a frame that can be recreated by an extrapolation of data from one or more preceding frames. Accordingly, on a frame-by-frame basis, each frame in a sequence of frames is identified as being critical or non-critical. Each frame that is identified as being critical is then transmitted in a manner that is more robust than the manner in which non-critical frames are transmitted to decrease the likelihood that a receiver will determine that the frame is erased. In a CDMA system, a current frame is identified as being critical by forming a weighted sum of the differences between corresponding frame parameters that represent the current frame and frame parameters that represent a previous frame. That weighted sum is compared with a threshold. If the weighted sum exceeds the threshold, then the current frame is classified as being a critical frame and is transmitted at a higher output level than non-critical frames are transmitted.
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公开(公告)号：CA2237826A1
公开(公告)日：1998-12-25
申请号：CA2237826
申请日：1998-05-19
Applicant: LUCENT TECHNOLOGIES INC
Inventor： WEAVER CARL FRANCIS , TARRAF AHMED A , MEYERS MARTIN HOWARD
Abstract: Telecommunications processing is applied to a reference signal to generate a signal under test. A fidelity measure is generated characterizing the fidelity of t he signal under test relative to the reference signal. A control signal is generated from the fid elity measure, where the control signal is used as a feedback signal to adjust the telecomm unications processing. In one embodiment, the reference signal is a speech signal and t he signal under test is a decoded speech signal generated by encoding, transmitting, and dec oding the reference speech signal. The fidelity signal is an average mean opinion scor e (MOS) and the control signal is used to control the speech decoding processing. For exampl e, the speech decoding processing may involve a speech decoder followed by a post filter, and the control signal is the cut-off frequency of the post filter. Such an embodiment may b e applied to real-time speech processing to adjust the speech decoding processing in the receiver of a telecommunications system that includes a speech encoder in a transmitter an d a communications network. Intermittently, the transmitter encodes reference si gnals that are also known to the receiver. The receiver performs the processing of the pres ent invention to update its speech decoding processing to optimize speech quality.
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公开(公告)号：AU750319B2
公开(公告)日：2002-07-18
申请号：AU4479099
申请日：1999-08-27
Applicant: LUCENT TECHNOLOGIES INC
Inventor： TARRAF AHMED A
IPC: H04L17/00 , H04L17/02 , H04L29/06 , H04L29/08 , H04M11/06 , H04W28/04 , H04L25/40 , H04B7/00 , H04Q7/20
Abstract: An apparatus and method for conveying teletype signals over a wireless telecommunication system. When the apparatus receives a teletype signal, it derives information carried by said signal and represents said information as at least one message. The at least one message and/or the teletype signal is transmitted over the wireless telecommunication system. When the apparatus receives a signal from the wireless telecommunication system that it determines to be a teletype signal, the apparatus of the present invention decodes the teletype information from part of the received signal determined as not having been adversely affected by the telecommunication system.
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Patent Agency Ranking
公开(公告)号：BR0100384A
公开(公告)日：2001-10-30
申请号：BR0100384
申请日：2001-02-07
Applicant: LUCENT TECHNOLOGIES INC
Inventor： SHERIF MAHMOUND RAGAEI , TARRAF AHMED A
Abstract: This invention is directed toward improving the subjective voice quality of a mobile to mobile phone call having tandem vocoder processing by modifying the spectrum of the voice signal before it is processed by the second vocoder to compensate for digital distortion which is generated by the second vocoder. An adaptive filter can be used to modify the spectrum of the voice signal. With this invention, the voice quality of a call from a first mobile phone to a second mobile phone has a quality that is substantially similar to the voice quality of a call from a mobile phone to a desk phone.
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公开(公告)号：AU1839001A
公开(公告)日：2001-08-16
申请号：AU1839001
申请日：2001-02-09
Applicant: LUCENT TECHNOLOGIES INC
Inventor： SHERIF MAHMOUD RAGAEI , TARRAF AHMED A
Abstract: This invention is directed toward improving the subjective voice quality of a mobile to mobile phone call having tandem vocoder processing by modifying the spectrum of the voice signal before it is processed by the second vocoder to compensate for digital distortion which is generated by the second vocoder. An adaptive filter can be used to modify the spectrum of the voice signal. With this invention, the voice quality of a call from a first mobile phone to a second mobile phone has a quality that is substantially similar to the voice quality of a call from a mobile phone to a desk phone.
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公开(公告)号：CA2330985A1
公开(公告)日：2001-08-14
申请号：CA2330985
申请日：2001-01-15
Applicant: LUCENT TECHNOLOGIES INC
Inventor： TARRAF AHMED A , SHERIF MAHMOUD RAGAEI
Abstract: This invention is directed toward improving the subjective voice quality of a mobile to mobile phone call having tandem vocoder processing by modifying the spectrum of the voice signal before it is processed by the second vocoder to compensate for digita l distortion which is generated by the second vocoder. An adaptive filter can be used to modify th e spectrum of the voice signal. With this invention, the voice quality of a call from a first mobile phone to a second mobile phone has a quality that is substantially similar to the voice qualit y of a call from a mobile phone to a desk phone.
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公开(公告)号：AU4479099A
公开(公告)日：2000-03-16
申请号：AU4479099
申请日：1999-08-27
Applicant: LUCENT TECHNOLOGIES INC
Inventor： TARRAF AHMED A
IPC: H04L17/00 , H04L17/02 , H04L29/06 , H04L29/08 , H04M11/06 , H04W28/04 , H04L25/40 , H04B7/00 , H04Q7/20
Abstract: An apparatus and method for conveying teletype signals over a wireless telecommunication system. When the apparatus receives a teletype signal, it derives information carried by said signal and represents said information as at least one message. The at least one message and/or the teletype signal is transmitted over the wireless telecommunication system. When the apparatus receives a signal from the wireless telecommunication system that it determines to be a teletype signal, the apparatus of the present invention decodes the teletype information from part of the received signal determined as not having been adversely affected by the telecommunication system.
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公开(公告)号：AU4462599A
公开(公告)日：2000-03-16
申请号：AU4462599
申请日：1999-08-20
Applicant: LUCENT TECHNOLOGIES INC
Inventor： TARRAF AHMED A
IPC: G10L19/12 , H04B7/02 , H04L1/08 , H04L17/00 , H04L17/02 , H04Q7/30 , H04L25/40 , H04B7/216 , H04Q7/20
Abstract: A method for conveying information-carrying teletype signals over a wireless telecommunication system by encoding the information into a repetitive signal. Teletype information is derived from part of a received signal encoded as a repetitive signal which part has been determined not to have been adversely affected by the wireless telecommunication system.
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