Telephonic communications – Echo cancellation or suppression – Disable or inhibit function
Reexamination Certificate
2005-03-15
2005-03-15
Isen, Forester W. (Department: 2644)
Telephonic communications
Echo cancellation or suppression
Disable or inhibit function
C379S406060
Reexamination Certificate
active
06868158
ABSTRACT:
An echo canceller has a high-pass filter11,a speaker3,an A/D converter6,and an echo canceller7. The high-pass filter11suppresses a low-frequency component in a received signal. The speaker3outputs an acoustic sound of a low-frequency suppressed received signal passed through the high-pass filter11.The A/D converter6converts an acoustic echo from a microphone4into a transmission signal of a digital form. The echo canceller7generates a pseudo echo signal based on the low-frequency suppressed received signal passed through the high-pass filter11,and eliminates the acoustic echo to be inputted to the microphone4from the speaker3by subtracting the pseudo echo signal from the digital signal converted by the A/D converter6.
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Kajiyama Ikuo
Matsuoka Bunkei
Takahashi Shinya
Harold Jefferey F.
Isen Forester W.
Mitsubishi Denki & Kabushiki Kaisha
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
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