SNR CALCULATION METHOD AND OPTICAL SPECTRUM MEASURING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method for more precisely measuring SNR in the measurement of SNR by use of an optical spectrum measuring device in a light source having a narrow space of adjacent signal wavelengths or by use of an optical spectrum measurement device having a poor dynamic range. SOLUTION: This SNR calculation method comprises a step for measuring the wavelength characteristic of the dynamic range in an optical spectrum measurement device every wavelength within a multiplexed wavelength range and storing it in a memory means; a step for measuring the signal level and noise level of an optical signal wavelength to be measured; a step for reading the noise level in which each of the other optical signal wavelengths multiplexed to the optical signal wavelength to be measured affects on the wavelength of the optical signal to be measured from the memory means; a step for subtracting the noise level read from the memory means to obtain a corrected noise level and a step for calculating the SNR of the optical signal to be measured from the signal level of the optical signal to be measured and the corrected noise level.