Patent ID: 7639744
Filing Date: 2009-12-29
Classification: H03H

Abstract:
1. A codec circuit having a programmable digital bandpass filter, for matching the filter characteristics of the codec circuit to a transmitted Pulse Code Modulation (PCM) signal, having at least one programmable digital high-pass filter and at least one programmable digital low-pass filter connected in series, and a signal identification device configured to identify a type of modulation and transmission speed of a PCM signal transmitted within the codec circuit to determine the transmitted PCM signal originates from a terminal or from a telephone and configured to set filter coefficients for the at least one programmable digital high-pass filter and the at least one programmable digital low-pass filter based on the identified type of modulation and transmission speed of the transmitted PCM signal to vary a bandpass filter characteristic for the programmable digital bandpass filter to match the determined origin of the transmitted PCM signal.