Patent ID: 7599483

Claim:
An echo canceler circuit comprising: an uplink data attenuator operative to receive post-echo canceler uplink data and uplink echo return loss based attenuation data and in response to attenuate the post-echo canceler uplink data to produce attenuated uplink data; and an echo return loss based attenuation data generator operatively coupled to the uplink data attenuator and operative to produce the uplink echo return loss based attenuation data in response to instantaneous echo return loss data, wherein the instantaneous echo return loss data is based on attenuated downlink data and pre-echo canceler uplink data, and wherein the echo return loss based attenuation data generator updates failsafe echo return loss data based on the instantaneous echo return loss data and updates standard echo return loss data based on the instantaneous echo return loss data when not in a double talk mode, wherein the echo return loss based attenuation data generator produces the uplink echo return loss based attenuation data based on (a) the standard echo return loss data when the echo return loss based attenuation data generator determines that at least one of: the standard echo return loss data and the failsafe echo return loss data indicates no problematic acoustic coupling channel, and (b) the failsafe echo return loss data when the echo return loss based attenuation data generator determines that at least one of: the standard echo return loss data and the failsafe echo return loss data indicates a problematic acoustic coupling channel.