公开(公告)号：JP2001231075A

公开(公告)日：2001-08-24

申请号：JP2000396370

申请日：2000-12-27

Applicant: LUCENT TECHNOLOGIES INC

Inventor： HUH YOUNG U ,  SHERIF MAHMOUD R

IPC: H04W88/18 ,  H04Q7/38

Abstract: PROBLEM TO BE SOLVED: To provide a radio communication method and system that allows a user at one end to easily attain transmission of a dual tone multi-frequency character from a radio equipment to a 2nd radio equipment completely in a tandem free operation without the need for setting to a tandem operation mode. SOLUTION: The system stays in a tandem free operation mode for the dual tone multi-frequency signaling to avoid delay and distortion in a CODEC used in a tandem operation mode and can preclude actual possibility of missing a dual tone multi-frequency character burst signal in existence at present due to a reason of required conditions about the existing timing.

公开(公告)号：JP2001272998A

公开(公告)日：2001-10-05

申请号：JP2001036934

申请日：2001-02-14

Applicant: LUCENT TECHNOLOGIES INC

Inventor： SHERIF MAHMOUD R ,  TARRAF AHMED A

IPC: G10L19/00 ,  G10L19/14 ,  G10L21/02 ,  H03M7/30 ,  H04B7/00

Abstract: PROBLEM TO BE SOLVED: To provide a method and device for improving calling speech quality by phone from a mobile station to a mobile station. SOLUTION: This method improves calling speech quality by phone from a mobile station to a mobile station by tandem vocoder processing, and compensates digital distortion caused by a 2nd vocoder by correcting the speech signal spectrum before the signal is processed by the 2nd vocoder. The speech signal spectrum is corrected by using an adaptive filter. According to this invention, calling speech quality by phone from a 1st mobile phone (mobile station) to a 2nd mobile phone (mobile station) is almost similar to calling speech quality by phone from a mobile phone to a desktop telephone.

公开(公告)号：DE60034302D1

公开(公告)日：2007-05-24

申请号：DE60034302

申请日：2000-12-21

Applicant: LUCENT TECHNOLOGIES INC

Inventor： HUH YOUNG U ,  SHERIF MAHMOUD R

IPC: H04W88/18

公开(公告)号：DE60001209T2

公开(公告)日：2003-11-13

申请号：DE60001209

申请日：2000-08-29

Applicant: LUCENT TECHNOLOGIES INC

Inventor： SHERIF MAHMOUD R ,  TARRAF AHMED A

IPC: G10L19/00 ,  G10L19/14 ,  G10L21/02 ,  H03M7/30 ,  H04B7/00

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.

公开(公告)号：DE60001209D1

公开(公告)日：2003-02-20

申请号：DE60001209

申请日：2000-08-29

Applicant: LUCENT TECHNOLOGIES INC

Inventor： SHERIF MAHMOUD R ,  TARRAF AHMED A

IPC: G10L19/00 ,  G10L19/14 ,  G10L21/02 ,  H03M7/30 ,  H04B7/00

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.

公开(公告)号：DE60034302T2

公开(公告)日：2007-12-20

申请号：DE60034302

申请日：2000-12-21

Applicant: LUCENT TECHNOLOGIES INC

Inventor： HUH YOUNG U ,  SHERIF MAHMOUD R

IPC: H04W88/18

公开(公告)号：BR0006812A

公开(公告)日：2001-09-18

申请号：BR0006812

申请日：2000-12-22

Applicant: LUCENT TECHNOLOGIES INC

Inventor： HUH YOUNG U ,  SHERIF MAHMOUD R

IPC: H04W88/18 ,  H04Q7/22