Patent ID: 6035004
Filing Date: 2000-03-07
Classification: H03D,H04L

Abstract:
A digital radio receiver comprising: receiving means for receiving an input signal; anddemodulating means for estimating the distortion of said input signal, eliminating said estimated distortion from said input signal to obtain a proper input signal, performing demodulation based on said proper input signal, and issuing a demodulated signal;wherein said receiving means includes an antenna for receiving a radio frequency, an RF/IF converter for converting said radio frequency to an intermediate frequency, an IO separator for separating I and O of said intermediate frequency, a filter for removing a noise from the output of said IO separator, and a multiplying sampler for sampling an output of said filter;wherein said demodulating means is a digital signal processing unit for performing quadrature phase demodulation based on said proper input signal;wherein I and Q phases are orthogonal, and said digital signal processing unit divides data on said sampled quadrature phase demodulated wave into groups on a basis of a plurality of IQ coordinates, estimates a parameter of an elliptical equation passing said plurality of IQ coordinates for each group, verifies said parameter for physical validity to select a group which has valid parameters, averages the parameters of said selected group, and removes distortion from the data on said quadrature phase demodulated wave according to the obtained mean value.