Patent ID: 6173058
Filing Date: 2001-01-09
Classification: H04M

Abstract:
A sound processing unit comprising:a vibration pick-up that detects a bone conduction sound and outputs it as a bone conduction sound signal;a double talk detector that compares a level of an input sound signal inputted through a first input terminal with a level of a transmitting signal inputted through a second input terminal, and outputs a state signal to indicate a receiving state when the level of the input sound signal is judged to be more than a first specific value and the level of the transmitting signal is judged to be less than a first specific value;a first adaptive filter that updates a first filter coefficient when the state signal indicates the receiving state, and generates to output a estimated-echo signal in accordance with the first filter coefficient on the basis of the input sound signal and an estimated bone conduction sound signal; anda first adder that subtracts the estimated-echo signal from the bone conduction sound signal to obtain and output the estimated bone conduction sound signal.