Patent ID: 7877062

Claim:
A mobile phone capable of filtering ambient noise, comprising: a storage unit; a microphone configured for receiving input audio signals and transforming the received input audio signals into analog signals; an analog-to-digital converter (ADC) configured for converting the analog signals from the microphone into digital signals; and a processing unit comprising: a sampling module configured for sampling the digital signals from the ADC to obtain sampled signals; an analyzing module configured for performing a Fourier transform on the sampled signals in each sampling period to obtain a plurality of frequency bands in each sampling period, computing a normal energy value of each frequency band by dividing an energy of the frequency band by a total energy of all the frequency bands, and determining the frequency band(s) whose normal energy value is greater than a predetermined normal energy value as the ambient noise frequency band(s), and storing the determined ambient noise frequency band(s), in each sampling period, in the storage unit; a filtering parameter determining module configured for statistically analyzing the ambient noise frequency bands in all sampling periods to determine main noise frequency band(s), and for storing the determined main noise frequency band(s) in the storage unit; and a filtering module configured for filtering out ambient noise having main noise frequency band(s) that are outside of a speech frequency band.