摘要 |
A telephone has a receiver, a transmitter, a control interface, an audio processor and a microprocessor. The audio processor includes a digital signal processor, an input audio unit coupled to a microphone, an output audio unit coupled to a speaker, and a ring signal controller coupled to a transducer/ringer. When an incoming call is received, the audio processor samples the microphone input signal, which is indicative of ambient noise, and performs a spectral analysis of the ambient noise. The audio processor then sets the ring frequency and the ring volume responsive to the ambient noise spectrum and the ring volume control level set by the user. |