SIGNAL QUALITY DETECTING DEVICE AND SIGNAL WAVE AMPLIFYING SYSTEM

摘要

PROBLEM TO BE SOLVED: To determine a signal quality by respective channels and on the whole channels even in signal waves of the plural channels for multiplexing an input wave on a wave length. SOLUTION: This signal quality detecting device is provided with (1) a signal wave wave length component taking-out means for taking out a wave length component of the signal waves from the input wave and (2) a signal quality estimating means for determining the signal quality by estimating power of the signal waves and power of a noise wave by using a difference in a polarization characteristic between the signal waves and the noise wave from a signal wave wave length component wave taken out by the signal wave wave length component taking-out means.