| 摘要 |
PROBLEM TO BE SOLVED: To suppress an amount of frequency variation, and also, to improve phase noise, without newly increasing a PLL circuit in a double-frequency converter. SOLUTION: The double-frequency converter is provided with a reference signal source which generates a reference signal for frequency conversion; a first local oscillator which oscillates to the reference signal from the reference signal source with a signal obtained via a first PLL circuit; a first mixer for outputting an intermediate frequency signal, by mixing an input signal with an oscillation signal of the first local oscillator; a second local oscillator which oscillates to the reference signal from the reference signal source with a signal obtained via a second PLL circuit; a third mixer for generating a difference frequency, between the oscillation signal of the first oscillator and that of the second local oscillator; and a second mixer for outputting the intermediate frequency signal and the output of the third mixer, after mixing them. COPYRIGHT: (C)2006,JPO&NCIPI
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