公开(公告)号：BR0206664A

公开(公告)日：2004-12-28

申请号：BR0206664

申请日：2002-01-23

Applicant: QUALCOMM INC

Inventor： EL-MALEH KHALED H ,  ANANTHAPADMANABHAN ARASANIPALA ,  DEJACO ANDREW P

IPC: G10L13/00 ,  G10L19/14 ,  G10L25/93 ,  G10L21/02

Abstract: Wideband speech signals must be converted to narrowband speech signals if the transmission medium or the destination terminal is constructed with narrowband constraints. A typical wideband-to-narrowband conversion method is the elimination of frequencies above 3400 Hz using a low pass filter and a down sampler. However, this method produces a muffled speech sound since the resulting narrowband signal has a flat frequency response. Methods and apparatus are presented herein to enhance the acoustic quality of a wideband-to-narrowband converted signal. A bandwidth switching filter is used to emphasize a mid-range frequency portion of the wideband signal so that the resulting narrowband signal has a non-flat frequency spectrum.

公开(公告)号：HK1051735A1

公开(公告)日：2003-08-15

申请号：HK03103998

申请日：2003-06-06

Applicant: QUALCOMM INC

Inventor： MANJUNATH SHARATH ,  DEJACO ANDREW P ,  ANANTHAPADMANABHAN ARASANIPALA ,  CHOY EDDIE LUN TIK

IPC: G10L19/04 ,  G10L19/00 ,  G10L19/12 ,  G10L19/14 ,  H03M7/36 ,  G10L

Abstract: A method and apparatus for using coding scheme selection patterns in a predictive speech coder to reduce sensitivity to frame error conditions includes a speech coder configured to select from among various predictive coding modes. After a predefined number of speech frames have been predictively coded, the speech coder codes one frame with a nonpredictive coding mode or a mildly predictive coding mode. The predefined number of frames can be determined in advance from the subjective standpoint of a listener. The predefined number of frames may be varied periodically. An average coding bit rate may be maintained for the speech coder by ensuring that an average coding bit rate is maintained for each successive pattern, or group, of predictively coded speech frames including at least one nonpredictively coded or mildly predictively coded speech frame.

公开(公告)号：BR0012543A

公开(公告)日：2003-07-01

申请号：BR0012543

申请日：2000-07-18

Applicant: QUALCOMM INC

Inventor： MANJUNATH SHARATH ,  DEJACO ANDREW P ,  ANANTHAPADMANABHAN ARASANIPALA ,  HUANG PENGJUN ,  CHOY EDDIE LUN TIK

IPC: G10L19/02 ,  G10L19/00 ,  G10L19/04 ,  G10L19/12 ,  H03M7/36

公开(公告)号：NO20020294L

公开(公告)日：2002-02-22

申请号：NO20020294

申请日：2002-01-18

Applicant: QUALCOMM INC

Inventor： MANJUNATH SHARATH ,  DEJACO ANDREW P ,  HUANG PENGJUN ,  CHOY EDDIE LUN TIK ,  ANANTHAPADMANABHAN ARASANIPALA

IPC: G10L19/02 ,  G10L19/00 ,  G10L19/04 ,  G10L19/12 ,  H03M7/36 ,  G10L

公开(公告)号：NO20020294A

公开(公告)日：2002-02-22

申请号：NO20020294

申请日：2002-01-18

Applicant: QUALCOMM INC

Inventor： MANJUNATH SHARATH ,  DEJACO ANDREW P ,  HUANG PENGJUN ,  CHOY EDDIE LUN TIK ,  ANANTHAPADMANABHAN ARASANIPALA

IPC: G10L19/04 ,  G10L19/00 ,  G10L19/12 ,  H03M7/36 ,  G10L

CPC classification number: G10L19/0208 ,  G10L19/10

Abstract: A method and apparatus for identifying frequency bands to compute linear phase shifts between frame prototypes in a speech coder includes partitioning the frequency spectrum of a prototype of a frame by dividing the frequency spectrum into segments, assigning one or more bands to each segment, and establishing, for each segment, a set of bandwidths for the bands. The bandwidths may be fixed and uniformly distributed in any given segment. The bandwidths may be fixed and non-uniformly distributed in any segment. The bandwidths may be variable and non-uniformly distributed in any given segment.

公开(公告)号：ES2322129T3

公开(公告)日：2009-06-17

申请号：ES02702129

申请日：2002-01-30

Applicant: QUALCOMM INC

Inventor： EL-MALEH KHALED H ,  ANANTHAPADMANABHAN ARASANIPALA ,  DEJACO ANDREW P

IPC: G10L19/012 ,  G10L13/00 ,  H04B14/04 ,  H04J3/00 ,  H04J13/00

Abstract: Un procedimiento para convertir tramas de habla no activa continuas en tramas de habla no activa discontinuas, en el que las tramas de habla no activa continuas están codificadas para un sistema de transmisión continua y en el que las tramas de habla no activa discontinuas están codificadas para un sistema de transmisión discontinua y que comprende: extraer información de ganancia y espectral de una pluralidad de tramas de habla no activa continuas (502); promediar la información de ganancia y espectral para lograr un parámetro de ganancia promedio y un parámetro espectral promedio (504); y generar al menos una trama de habla no activa discontinua usando el parámetro de ganancia promedio y el parámetro espectral promedio (506).

公开(公告)号：DE60231859D1

公开(公告)日：2009-05-20

申请号：DE60231859

申请日：2002-01-30

Applicant: QUALCOMM INC

Inventor： EL-MALEH KHALED H ,  ANANTHAPADMANABHAN ARASANIPALA ,  DEJACO ANDREW P

IPC: G10L19/012 ,  G10L13/00 ,  H04B14/04 ,  H04J3/00 ,  H04J13/00

Abstract: The disclosed embodiments provide a method and apparatus for interoperability between CTX and DTX communications systems during transmissions of silence or background noise. Continuous eight rate encoded noise frames are translated to discontinuous SID frames for transmission to DTX systems (402-410). Discontinuous SID frames are translated to continuous eight rate encoded noise frames for decoding by a CTX system (602-606). Applications of CTX to DTX interoperability comprise CDMA and GSM interoperability (narrowband voice transmission systems), CDMA next generation vocoder (The Selectable Mode Vocoder) interoperability with the new ITU-T 4 kbps vocoder operating in DTX-mode for Voice Over IP applications, future voice transmission systems that have a common speech encoder/decoder but operate in differing CTX or DTX modes during speech non-activity, and CDMA wideband voice transmission system interoperability with other wideband voice transmission systems with common wideband vocoders but with different modes of operation (DTX or CTX) during voice non-activity).

公开(公告)号：DE60128677T2

公开(公告)日：2008-03-06

申请号：DE60128677

申请日：2001-04-20

Applicant: QUALCOMM INC

Inventor： ANANTHAPADMANABHAN ARASANIPALA ,  MANJUNATH SHARATH ,  HUANG PENGJUN ,  CHOY EDDIE-LUN TIK ,  DEJACO ANDREW P

IPC: G10L19/04 ,  G10L19/08 ,  G10L11/00 ,  G10L19/02 ,  G10L19/14 ,  G10L25/90 ,  H03M7/36

Abstract: 13. A computer-readable medium comprising instructions that upon execution in a processor cause the processor to perform the methods as recited in any of claims 5 to 8.

公开(公告)号：AU2002235538B2

公开(公告)日：2008-02-07

申请号：AU2002235538

申请日：2002-02-06

Applicant: QUALCOMM INC

Inventor： DEJACO ANDREW P ,  CHOY EDDIE-LUN TIK ,  ANANTHAPADMANABHAN ARASANIPALA

IPC: G10L19/00 ,  G01L19/14 ,  G10L19/02 ,  G10L19/14

Abstract: A method and apparatus for enhancing coding efficiency by reducing illegal or other undesirable packet generation while encoding a signal, The probability of generating illegal or other undesirable packets while encoding a signal is reduced by first analyzing a history of the frequency of codebook values selected while quantizing speech parameters. Codebook entries are then positioned so that the index/indices that create illegal or other undesirable packets contain the least frequently used entry/entries. Positioning multiple codebooks for various parameters further reduces the probability, that an illegal or other undesirable packet will be created during signal encoding. The method and apparatus may be applied to reduce the probability of generating illegal null traffic channel data packets while encoding eight rate speech.

公开(公告)号：DE60128677D1

公开(公告)日：2007-07-12

申请号：DE60128677

申请日：2001-04-20

Applicant: QUALCOMM INC

Inventor： ANANTHAPADMANABHAN ARASANIPALA ,  MANJUNATH SHARATH ,  HUANG PENGJUN ,  CHOY EDDIE-LUN TIK ,  DEJACO ANDREW P

IPC: G10L19/04 ,  G10L19/08 ,  G10L11/00 ,  G10L19/02 ,  G10L19/14 ,  G10L25/90 ,  H03M7/36

Abstract: 13. A computer-readable medium comprising instructions that upon execution in a processor cause the processor to perform the methods as recited in any of claims 5 to 8.