| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable a measurement of a signal level with high accuracy in a shorten measurement time in a spectrum analyzer for inputting a frequency signal to an object to be measured such as a crystal oscillator and a filter, sweeping the frequency signal and acquiring frequency characteristics of the object to be measured. <P>SOLUTION: A first frequency signal input to an object to be measured and a second frequency signal which is a local frequency signal are swept in synchronization. A frequency of a difference between the first frequency signal and the second frequency signal obtained is input to a band pass-filter of narrow band in a mixer. When a signal level measured by a measurement part is larger than a threshold value, a frequency signal from the mixer is made to bypass the band-pass filter of narrow band so as to make the sweep rate higher. <P>COPYRIGHT: (C)2012,JPO&INPIT |
