Patent ID: 6944241

Claim:
An apparatus for eliminating a vestigial sideband (VSB) pilot tone in a vestigial sideband/quadrature amplitude modulation (VSB/QAM) shared receiving system including a VSB/QAM shared demodulator for demodulating a received VSB signal and outputting I-axis VSB symbols and Q-axis VSB symbols, the apparatus comprising: an I-axis pilot tone eliminating unit for dividing the I-axis VSB symbols into a first plurality of groups according to the sign of an I-axis pilot tone which remains in each symbol, obtaining the value of the I-axis pilot tone by calculating the average of VSB symbols in each of the first plurality of groups, and eliminating the I-axis pilot tone by adding the value of the I-axis pilot tone to or subtracting the value of the I-axis pilot tone from the I-axis VSB symbols; and a Q-axis pilot tone eliminating unit for dividing the Q-axis VSB symbols into a second plurality of groups according to the sign of a Q-axis pilot tone which remains in each symbol, obtaining the value of the Q-axis pilot tone by calculating the average of VSB symbols in each of the second plurality of groups, and eliminating the Q-axis pilot tone by adding the value of the Q-axis pilot tone to or subtracting the value of the Q-axis pilot tone from the Q-axis VSB symbols.