| 摘要 |
A sweeping device is provided to satisfy sweeping function and to perform stabilized lock property by changing a reference frequency by frequency changing part. A fractional divider, a phase detector, and a charge pump are integrated in a fractional synthesizer device(130). The fractional divider changes a frequency of an input signal. The phase detector detects a phase difference of signals having an input signal and a reference frequency. A division value which is a reciprocal of division ratio is fixed in the fractional synthesizer device. An oscillator(160) supplies an input signal to the fractional synthesizer device. A frequency changing part changes a reference frequency of a signal inputted in the fractional synthesizer device, and includes a direct digital synthesizer(120). |
