To output frequency signals over wide bands by changing a high-frequency signal outputted by a phase locked loop(PLL) circuit and using that signal for the down conversion of a mixer.
A mixer 10 performs up conversion with a high-frequency signal outputted by a signal source 40 to a source oscillation signal. This up-converted signal is passed only for 9.184 GHz by a band-pass filter(BPF) 20. A mixer 51 performs down conversion to a signal, which is outputted by a voltage controlled oscillator(VCO) 55, with the high-frequency signal outputted by the signal source 40. This down-converted signal is frequency-divided into 1/4 by a prescaler 52. Then, the frequency-divided signal is inputted to a phase comparator 53 and compared with a reference signal, and a phase difference signal is outputted. This phase difference signal is inputted via an amplifier 54 to the VCO 55, and a high-frequency signal is outputted. Then, a mixer 30 performs down the conversion to the signal from the BPF 20 with the signal from the VCO 55.
| WO/2021/139746 | TRANSMITTER WITH REDUCED VCO PULLING |
| JP2005295544 | HIGH PERFORMANCE SIGNAL GENERATION |
INAGAKI TETSURO
KUMAGAI MITSUHIRO
