Patent ID: 7627295

Claim:
A downconverter for downconverting a Radio Frequency (RF) signal, comprising: a complex-coefficient transversal filter for generating a real part of a complex RF signal by performing a convolution integral according to a generated impulse response based on an even function for an input RF signal, generating an imaginary part of the complex RF signal by performing a convolution integral according to a generated impulse response based on an odd function for the input RF signal, rejecting one side of a positive or negative frequency, and outputting the complex RF signal; a local oscillator for outputting a real local signal at a set frequency; and a complex mixer, connected to the complex-coefficient transversal filter and the local oscillator, for performing a frequency conversion process by multiplying the complex RF signal output from the complex-coefficient transversal filter and the real local signal output from the local oscillator, and outputting a complex signal of a frequency separated by the set frequency from a frequency of the RF signal.