Patent ID: 6232761
Filing Date: 2001-05-15
Classification: H04L

Abstract:
A frequency estimating system for estimating a center frequency of carrier wave of a received signal subjected to the influence of fading in the transmission line, comprising:means for obtaining power-frequency spectrum of the carrier wave of the received signal;peak detection means for obtaining a peak power level from the power-frequency spectrum of the carrier wave and obtaining a peak power level frequency corresponding to the peak power level; andfirst frequency level detection means for detecting a first frequency, which is higher than the peak power level frequency and having a power level lower than the peak power level by a predetermined value, as a first lower power level frequency;second frequency level detection means for detecting a second frequency, which is lower than the peak power level frequency and having a power level lower than the peak power level by the predetermined value, as a second lower power level frequency; andaveraging means for obtaining the estimated center frequency by averaging the first and second lower power level frequencies.