DAC architecture for analog echo cancellation

Year	Description
1998	Invention patented by Michael O. Polley and William J. Bright on April 29th, 1998. Abstract: Echo cancellation in data communication between modems utilizes analog echo cancellation to lessen reduction of usable dynamic range of the received signal at the input to the analog-to-digital converter (DAC) in the receiver. Two digital-to analog (D/A) conversions are provided in the modem's analog front end (AFE). One generates the analog signal for transmission. The other generates an analog representation of a cancellation signal that is used to electronically cancel the echo before analog-to-digital (A/D) conversion of the received signal. A preferred embodiment utilizes multiplexed DAC architecture to emulate two DACs by sharing DAC circuitry between data paths of the two D/A conversions.
Source: selected by the editor from original sources.

Invention: DAC architecture for analog echo cancellation