Patent ID: 7756228
Filing Date: 2010-07-13
Classification: H04L

Abstract:
1. A transceiver system comprising (a) a primary transmitter for providing a primary symbol-information-carrying output signal and (b) a primary receiver for receiving a primary symbol-information-carrying input analog signal that includes an echo of the output signal, the receiver comprising: analog echo-cancelling circuitry for adaptively operating on the input analog signal, or on a first intermediate analog signal generated from the input analog signal, to produce an echo-reduced analog signal in which the echo is reduced; an analog-to-digital converter for converting the echo-reduced analog signal, or a second intermediate analog signal generated from the echo-reduced analog signal, into an initial digital signal; digital echo-cancelling circuitry for adaptively operating on the initial digital signal, or on a first intermediate digital signal generated from the initial digital signal, to produce an echo-reduced digital signal in which the echo is further reduced; and an output decoder for decoding the echo-reduced digital signal, or a second intermediate digital signal generated from the echo-reduced digital signal, into a stream of symbols, the echo-cancelling circuitries having echo-filtering characteristics that are adaptively adjustable during conversion of the input analog signal into the stream of symbols, both echo-cancelling circuitries adaptively adjusting their echo-filtering characteristics in response to an error signal generated by decoding the echo-reduced digital signal or a further digital signal generated from the echo-reduced digital signal.