| 摘要 |
PROBLEM TO BE SOLVED: To provide a low noise converter in which a cross polarized component propagated on a signal line is reduced by reducing gains of frequency bands except for a receiving band on the side of narrow band polarization. SOLUTION: In the low noise converter for satellite broadcasting for converting the frequencies of received frequency signals of L and R polarized waves (or of H and V polarized waves) to intermediate frequencies, the receiving frequency band of one side of polarization is selected to be a high frequency band only in the receiving frequency band of the other side of polarization, and by inserting a trap circuit for reducing the gains of low frequencies to an LNA part in relation to amplifiers 21 and 22 in which the receiving frequency band is selected to a high frequency band among LNA 20 for amplifying the received signal of each polarized wave into low noise, the cross polarized component of the low frequency propagated on the signal line on a narrow band side is suppressed. COPYRIGHT: (C)2004,JPO
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