Patent ID: 8503510

Claim:
A noise removing method that can use a communication device comprising a communication antenna that receives a transmission signal where a spectrum spread signal subjected to a spectrum spread is modulated, an intermediate frequency converting unit that converts the transmission signal received by the communication antenna into an intermediate frequency signal having a predetermined frequency, and an analog to digital converting unit that discretizes the intermediate frequency signal and outputs a discretization signal, and removes a noise other than a normal thermal noise included in the discretization signal, the noise removing method comprising the steps of: performing a fast Fourier transform on the discretization signal; detecting a frequency whose amplitude is a predetermined value or more as a peak frequency of the noise, based on a result of the fast Fourier transform in the performing of the fast Fourier transform; and outputting a discretization signal where a frequency component corresponding to the peak frequency detected in the detecting of the frequency is attenuated, based on the discretization signal, and without performing a feedback operation on the outputted, discretization signal.