Patent ID: 6097971
Filing Date: 2000-08-01
Classification: H04M

Abstract:
A hands-free speech communication apparatus incorporating an echo canceler in a mobile telephone, said communication apparatus comprising:howling prevention means for preventing howling caused due to leakage of a mobile-side loudspeaker output into a mobile-side microphone input during hands-free speech communication;echo cancel means for canceling an echo generated due to leakage of a transmission voice signal from a self line output terminal into a reception voice signal input to a self line input terminal,wherein said howling prevention means and said echo cancel means are constituted by a one-chip digital signal processor, and said digital signal processor is controlled by a microprocessor incorporated in an external cellular phone, thereby controlling operation parameters of said howling prevention means and said echo cancel means on the basis of software; anda parameter reception processing interface to provide operating parameters to said howling prevention means and said echo cancel means from said external microprocessor.