| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high frequency oscillator capable of effectively suppressing spurious. <P>SOLUTION: An electric transmission system 15 includes an oscillator 9, a first coupler 8, a first mixer 5, a band pass filter 7, and a second mixer 6. The first coupler 8 branches an RF signal having a second frequency from the oscillator 9 into two. The first mixer 5 mixes RF signals from an O/E converter 4 and the first coupler 8 to generate two RF signals. The band pass filter 7 allows only a signal component included in a prescribed pass band having a third frequency as the center frequency, to pass through, from the two RF signals from the first mixer 5. The second mixer 6 mixes RF signals from the band pass filter 7 and the first coupler 8 to generate two RF signals. The third frequency is set to a value lower than a first frequency being a frequency of an RF signal outputted from this high frequency oscillator. <P>COPYRIGHT: (C)2009,JPO&INPIT |
