| 摘要 |
PROBLEM TO BE SOLVED: To realize a wide frequency variable range and low phase noise.SOLUTION: A microwave signal generator includes a YIG oscillator 41 for oscillating and outputting a microwave band signal at a variable frequency according to a voltage of a control signal Vc, a frequency discriminator 50 for discriminating frequency of the output signal, a frequency setting device 65 for setting output frequency designation information of the YIG oscillator 41, and a control part 60 for providing a control signal Vc, generated according to the output of the frequency discriminator 50 and setting information of the frequency setting device 65, to the YIG oscillator 41. The frequency discriminator 50 includes a delay circuit 51 using an optical fiber delay line 54, and a quadrature detector 56 for outputting an in-phase component and a quadrature-phase component for identifying a phase difference between the output of the YIG oscillator 41 and the output of the delay circuit 51. The control part 60 sets the output frequency of the YIG oscillator 41 and suppresses phase noise by performing an operation using the output of the quadrature detector 56 and the frequency setting information, and providing the control signal Vc, according to a signal which is phase rotated output of the quadrature detector, to the YIG oscillator 41. |
