AGC circuit for an echo cancelling circuit

摘要

An amplifier circuit and a method of amplification using automatic gain control (AGC) are disclosed. A method for reducing distortions incurred by an audio signal when being rendered by an electronic device is described. The method comprises receiving an input signal; determining signal strength; determining a frequency-dependent AGC filter; wherein the frequency-dependent AGC filter is adapted to selectively attenuate the input signal within a number N of predetermined frequency ranges, according to corresponding N degrees of attenuation; wherein N predetermined frequency ranges depend upon a rendering characteristic of the electronic device; and wherein the N-degrees of attenuation depend upon the signal strength; and attenuating the input signal using the frequency-dependent AGC filter to obtain an output signal for rendering by the electronic device.

主权项

1. A method for reducing distortions incurred by an audio signal when being rendered by an electronic device, the method comprising:
receiving an input signal; determining a signal strength based on the input signal; determining a frequency-dependent AGC filter; wherein the frequency-dependent AGC filter is configured to selectively attenuate the input signal within a number N of predetermined frequency ranges, N being an integer, N>0, according to corresponding N degrees of attenuation; wherein the N predetermined frequency ranges depend upon a rendering characteristic of the electronic device; wherein the N degrees of attenuation depend upon the signal strength; wherein each of the N predetermined frequency ranges comprises a center frequency and an distortion bandwidth; wherein the input signal comprises non-distorting components at frequencies which are not comprised within the N predetermined frequency ranges; and the non-distorting components are not substantially attenuated by the frequency-dependent AGC filter; and attenuating the input signal using the frequency-dependent AGC filter to obtain an output signal for rendering by the electronic device.