Patent ID: 8804791

Claim:
A communication device, comprising: a display unit; an operation unit coupled to the display unit; a communication antenna coupled to a control unit, wherein the communication antenna receives a transmission signal where a spectrum spread signal subjected to a spectrum spread is modulated; at least one processor, coupled to the operation unit and the display unit, configured to convert the transmission signal received by the communication antenna into an intermediate frequency signal having a predetermined frequency; an analog to digital converting unit that discretizes the intermediate frequency signal and outputs a discretization signal; a noise removing unit that detects a noise other than a normal thermal noise included in the discretization signal and removes the detected noise from the discretization signal, wherein the noise removing unit includes: a Fourier transforming unit that performs a fast Fourier transform on the discretization signal and derives a power spectrum based on a result of the fast Fourier transform; and a Wiener filter that outputs a discretization signal that minimizes a mean squared error with respect to an ideal discretization signal in an ideal state not including the noise, based on the discretization signal, the power spectrum output from the Fourier transforming unit, and a reference power per unit frequency; and a demodulating unit that demodulates the spectrum spread signal, based on the discretization signal that is output from the noise removing unit.