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公开(公告)号：FR2692089B1
公开(公告)日：1996-06-21
申请号：FR9304308
申请日：1993-04-13
Applicant: MOTOROLA INC
Inventor： ASHLEY JAMES P , NGUYEN QUOC
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公开(公告)号：FR2722627A1
公开(公告)日：1996-01-19
申请号：FR9507222
申请日：1995-06-16
Applicant: MOTOROLA INC
Inventor： ASHLEY JAMES P , PROCTOR LEE MICHAEL
Abstract: A method and apparatus are provided for echo cancelling which includes double-talk immunity. The echo canceller (15) according to the present invention includes a double-talk detector (17) which uses an adaptive double-talk detection threshold (214) and an accurate estimation of reference energy (106) to detect double-talk. The echo canceller further provides for correcting partial echo canceller adaptive filter vector divergence occurring prior to double-talk detection by maintaining and switching to an auxiliary echo canceller filter with known "good" filter coefficients (58, 60, 62).
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公开(公告)号：BRPI9709148B8
公开(公告)日：2016-05-31
申请号：BR9709148
申请日：1997-11-04
Applicant: MOTOROLA MOBILITY INC , MOTOROLA SOLUTIONS INC , MOTOROLA INC
Inventor： ASHLEY JAMES P , PROCTOR LEE M
Abstract: aparelho e processo para processamento não-linear em um sistema de comunicações . um processador não-linear aperfeiçoado utilizado em cancelamento de eco elimina uma fonte de ruído de conforto (214) e em vez disso introduz um sinal de controle (224) diretamente em um sistema de supressão de ruído (403). o sistema de supressão de ruído (403) usa o sinal de controle (224) para inibir a atualização iterativa da estimativa de ruído de fundo quando o sinal de controle (224) está ativo, o que impede que qualquer eco residual influente a estimativa de ruído fornecido pelo sistema de supressão de ruído (403). além disso, o sinal de controle (224) é utilizado por um calculador de ganho (533) dentro do sistema de supressão de ruído (403) para atenuar cada faixa de frequência até o máximo permissível mais a razão entre sinal-ruído (snr) de canal residual atual. dependendo da implementação, o sistema de supressão de ruído (403) modela o ruído de fundo ou de um usuário do pstn ou de um usuário de uma estação móvel.
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44.发明专利
公开(公告)号：BRPI0817800A2
公开(公告)日：2015-03-24
申请号：BRPI0817800
申请日：2008-09-25
Applicant: MOTOROLA INC
Inventor： ASHLEY JAMES P , GIBBS JONATHAN ALASTAIR , MITTAL UDAR
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公开(公告)号：AT328407T
公开(公告)日：2006-06-15
申请号：AT99943854
申请日：1999-08-24
Applicant: MOTOROLA INC
Inventor： ASHLEY JAMES P , PENG WEIMIN
Abstract: To achieve high quality speech reconstruction at low bit rates, constraints on position combinations among two or more pulses (403) are implemented. By placing constraints on position combinations, certain combinations of pulses are prohibited which allows the most significant pulses to always be coded, thereby improving speech quality. After all valid combinations are considered, a list of pulse pairs (codebook) which can be indexed using a single, predetermined bit length codeword is produced. The codeword is transmitted to a destination where it is used by a decoder to reconstruct the original information signal.
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Patent Agency Ranking
公开(公告)号：FI115582B
公开(公告)日：2005-05-31
申请号：FI972852
申请日：1997-07-03
Applicant: MOTOROLA INC
Inventor： ASHLEY JAMES P
Abstract: A noise suppression system implemented in communication system provides an improved update decision during instances of sudden increase in background noise level. The noise suppression system, inter alia, generates an update by continually monitoring the deviation of spectral energy and forcing an update based on a predetermined threshold criterion. The spectral energy deviation is determined by utilizing an element which has the past values of the power spectral components exponentially weighted. The exponential weighting is a function of the current input energy, which means the higher the input signal energy the longer the exponential window. Conversely, the lower the signal energy the shorter the exponential window. The noise suppression system also inhibits a forced update during periods of continuous, non-stationary input signals (such as "music-on-hold").
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公开(公告)号：CA2542137A1
公开(公告)日：2005-05-19
申请号：CA2542137
申请日：2004-10-26
Applicant: MOTOROLA INC
Inventor： MITTAL UDAR , ASHLEY JAMES P
Abstract: To address the need for choosing values of harmonic noise weighting (HNW) coefficient (epsilon p ) so that the amount of harmonic noise weighting can be optimized, a method and apparatus for performing harmonic noise weighting in digital speech coders is provided herein. During operation, received speech is analyzed to determine a pitch period. HNW coefficients are then chosen based on the pitch period, and a perceptual noise weighting filter (C(z)) is determined based on the harmonic-noise weighting (HNW) coefficients (epsilon p ).
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公开(公告)号：DE69823656T2
公开(公告)日：2004-10-07
申请号：DE69823656
申请日：1998-02-18
Applicant: MOTOROLA INC
Inventor： DECLERCK DANIEL J , ASHLEY JAMES P
Abstract: A mobile station (106) in a code division multiple access (CDMA) communication system (100) implements scanning of pilot channels on a different frequency by reserving a periodic frame on the forward channel to allow the mobile station (106) to change frequencies and scan for other pilot channels. To preserve some aspects of voice quality, both the base station (102) and mobile station (106) voice encode speech at a maximum of half rate and transmit the information as secondary traffic prior to the frame where the mobile station (106) scans the alternate frequency. To maximize the trade-off between voice quality and frequency of the scan, the base station (102) indicates to the mobile station (106) the period between other frequency scans via messaging. To ensure compatibility, this method can be negotiated via known service configuration negotiation techniques.
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公开(公告)号：DE69823656D1
公开(公告)日：2004-06-09
申请号：DE69823656
申请日：1998-02-18
Applicant: MOTOROLA INC
Inventor： DECLERCK DANIEL J , ASHLEY JAMES P
Abstract: A mobile station (106) in a code division multiple access (CDMA) communication system (100) implements scanning of pilot channels on a different frequency by reserving a periodic frame on the forward channel to allow the mobile station (106) to change frequencies and scan for other pilot channels. To preserve some aspects of voice quality, both the base station (102) and mobile station (106) voice encode speech at a maximum of half rate and transmit the information as secondary traffic prior to the frame where the mobile station (106) scans the alternate frequency. To maximize the trade-off between voice quality and frequency of the scan, the base station (102) indicates to the mobile station (106) the period between other frequency scans via messaging. To ensure compatibility, this method can be negotiated via known service configuration negotiation techniques.
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公开(公告)号：HU9800843A2
公开(公告)日：1998-07-28
申请号：HU9800843
申请日：1996-09-04
Applicant: MOTOROLA INC
Inventor： ASHLEY JAMES P
Abstract: A noise suppression system implemented in communication system provides an improved update decision during instances of sudden increase in background noise level. The noise suppression system, inter alia, generates an update by continually monitoring the deviation of spectral energy and forcing an update based on a predetermined threshold criterion. The spectral energy deviation is determined by utilizing an element which has the past values of the power spectral components exponentially weighted. The exponential weighting is a function of the current input energy, which means the higher the input signal energy the longer the exponential window. Conversely, the lower the signal energy the shorter the exponential window. The noise suppression system also inhibits a forced update during periods of continuous, non-stationary input signals (such as "music-on-hold").
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