Echo canceler circuit and method

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;
• a downlink data attenuator operative to receive downlink data and downlink echo return loss based attenuation data and in response to attenuate the downlink data to produce attenuated downlink data;
• and
• an echo return loss based attenuation data generator operatively coupled to the uplink data attenuator and the downlink data attenuator and operative to produce the uplink echo return loss based attenuation data and the downlink 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 and the downlink 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.

A communication apparatus comprising:

• a housing having coupled therewith:
• an echo canceler circuit within the housing including:
• 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;
• 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;
• and
• a transceiver within the housing operatively coupled to the uplink data attenuator and operative to receive the attenuated uplink data and in response to transmit the attenuated uplink data.

An in-vehicle communication system comprising:

• 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;
• 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;
• a wireless transceiver operatively coupled to the uplink data attenuator and operative to receive the attenuated uplink data and in response to transmit the attenuated uplink data;
• an audio system including:
• an amplifier, operatively coupled to the echo canceler circuit, and operative to receive the attenuated downlink data and in response to produce an amplified downlink audio signal;
• and
• a playback module including at least one of:
• a tuner module, a tape player, a CD player, a DVD player, operatively coupled to the amplifier and operative to provide a playback audio signal to the amplifier.