Abstract:
The device is structured to have a first electric modulation signal generator, a second electric modulation signal generator, a two-mode beat light source and an optical intensity modulator. The first electric modulation signal generator generates and outputs a first electric modulation signal. The second electric modulation signal generator generates and outputs a second electric modulation signal of a same frequency as the first electric modulation signal and to which a phase difference of δ radians is provided (δ is a real number satisfying 0≦̸δ≦̸&pgr;). The two-mode beat light source is driven by the first electric modulation signal, and generates and outputs two-mode beat light. The two-mode beat light is inputted to the optical intensity modulator, and the optical intensity modulator generates and outputs a CS optical pulse train. Light transmittance of the optical intensity modulator is modulated by the second electric modulation signal.
Abstract:
PROBLEM TO BE SOLVED: To provide a modulation light source that allows downsizing and a method of generating a modulation signal.SOLUTION: A modulation signal generating device 200 includes: a voltage source 221 generating a driving modulation voltage Vm that is set according to phase modulation of a signal string; and a control circuit 222 generating a modulation voltage Vp according to the driving modulation voltage Vm and applying the modulation voltage Vp to a frequency modulation region 104 of a light source part.