Transmission apparatus having echo cancellation facility
Patent 5896420 Issued on April 20, 1999. Estimated Expiration Date: 
November 21, 2016. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
November 21, 2016. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesEcho canceller Digital voice transmission having improved echo suppression PCM coder and decoder having function of two-wire/four-wire conversion High speed two wire modem Patent #: 5347539 InventorsAssigneeApplicationNo. 749346 filed on 11/21/1996US Classes:375/285, Antinoise or distortion370/286, Echo suppression or cancellation375/296, Antinoise or distortion (includes predistortion)375/346, Interference or noise reduction379/402, Hybrid circuit379/406.06Using digital signal processingExaminersPrimary: Le, Amanda T.Attorney, Agent or FirmForeign Patent References
International ClassH04B 003/20Foreign Application Priority Data1996-02-19 JPAbstractA transmission apparatus, connected via a hybrid circuit to a line, such as a modulator-demodulator which can perform stable echo cancellation, whether the level of the far-end echo is high or not, provided with a transmission unit which generates a transmission signal to be transmitted to the line via the hybrid circuit, a reception unit which receives the reception signal supplied from the line via the hybrid circuit, and a superimposing means for superimposing the reception signal applied to the hybrid circuit onto the transmission signal. The transmission signal onto which the reception signal is superimposed by the superimposing means is transmitted to the line via the hybrid circuit. | |
