Patent ID: 6115473
Filing Date: 2000-09-05
Classification: H03D,H04H

Abstract:
A receiving apparatus for receiving digital broadcasting including a first frequency band and a second frequency band, said receiving apparatus comprising:first local oscillation means for generating a first local oscillation signal;frequency conversion means for generating a second local oscillation signal by frequency-converting said first local oscillation signal;first mixer means for frequency-converting a first frequency signal of said first frequency band to a first intermediate frequency signal using one of said first local oscillation signal and said second local oscillation signal;second mixer means for frequency-converting a second frequency signal of said second frequency band to said first intermediate frequency signal using one of said first local oscillation signal and said second local oscillation signal;second local oscillation means for generating a third local oscillation signal; andthird mixer means, whereinone of a first local oscillation signal frequency of said first local oscillation signal and a second local oscillation signal frequency of said second local oscillation signal is increased to a frequency higher than said first frequency band, and said first frequency signal of said first frequency band is frequency-converted to said first intermediate frequency signal in said first mixer means by up-conversion,the other of said first local oscillation signal frequency of said first local oscillation signal and said second local oscillation signal frequency of said second local oscillation signal is decreased to a frequency lower than said second frequency band, and said second frequency signal of said second frequency band is frequency-converted to said first intermediate frequency signal in said second mixer means by down-conversion,said first intermediate frequency signal output from said second mixer means is supplied to said third mixer means when said second frequency band is received and said first intermediate frequency signal output from said first mixer means is supplied to said third mixer means when said first frequency band is received,said first intermediate frequency signal output from one of said first mixer means and said second mixer means is frequency-converted to a second intermediate frequency signal in said third mixer means using said third local oscillation signal,a digital signal comprising an I-component and a Q-component is generated by performing A/D conversion and separation into said I-component and said Q-component on said second intermediate frequency signal, andoriginal digital data is extracted from said digital signal comprising said I-component and said Q-component.