Title:
エコーキャンセレーションシステムをもつラウドスピーカ-マイクロフォンシステム、及びエコーキャンセレーションのための方法
Document Type and Number:
Japanese Patent JP2007502593
Kind Code:
A
Abstract:
A two way sound reproduction system, such as a mobile phone system has an input ( 2 ) for an incoming far end signal (W), a loudspeaker ( 5 ), a D-to-A-converter ( 3 ) between the input ( 2 ) and the loudspeaker ( 5 ), a microphone ( 7 ), a A-to-D ( 8 ) converter after the microphone ( 7 ), an echo cancellation system (AEC) and an output ( 12 ) for an outgoing far end signal. The system comprises a pre-processor ( 30 ) between the input ( 2 ) and the D-to-A converter ( 3 ) comprising: an amplifier ( 32 ) to amplify the signal to a sufficient sound pressure level, a clipper or compressor or limiter ( 33 ) to limit the signal in the digital domain, so that the telephone system between D-to-A converter ( 3 ) and A-to-D converter ( 8 ) behaves substantially like a linear system.
Inventors:
Mercus, Ifo El D'em
Loafels, Derfitt SAME
Alexander, Stenger
Loafels, Derfitt SAME
Alexander, Stenger
Application Number:
JP2006530875A
Publication Date:
February 08, 2007
Filing Date:
May 18, 2004
Export Citation:
Assignee:
Koninklijke Philips Electronics N.V.
International Classes:
H04M1/60; H04B3/23; H04M9/08; H04R3/02
Attorney, Agent or Firm:
Tadahiko Ito
Shinsuke Onuki
Tadashige Ito
Shinsuke Onuki
Tadashige Ito