| 摘要 |
PURPOSE:To execute a tracking even when a background light with an intensity comparatively large such as a sunlight is made incident by controlling the distribution factor of the signal power of a signal light detected according to a tracking stability coefficient operated from the data of a signal-to-noise ratio from an opponent station at a self-station. CONSTITUTION:In response to a comparison result outputted from a comparator 26, a control device 28 outputs a control signal C1 to a wavelength plate rotating driver 29 and a laser driver 17 when an interference due to the sunlight is not generated and a stability coefficient K is below a constant L. On the other hand, a storage device 25 stores the stability coefficient K outputted from an arithmetic device 24 as a stability coefficient K0 at the time of a non- interference. In response to the control signal C1, the wavelength plate rotating driver 29 rotates a wavelength plate 20, a variable light distributer 40 is made into a second control condition, the laser driver 17 amplifiers a driving current inputted from a modulator 16 by a prescribed first amplification degree, and the current is outputted to a laser 18. |
