Patent ID: 7471902
Filing Date: 2008-12-30
Classification: H04J

Abstract:
1. A wavelength allocation method of allocating signal lights on wavelength grids, where previously determined wavelength spacing in the wavelength grids is a base unit, the allocated signal lights being used in wavelength division multiplexing optical transmission in which wavelength division multiplexed signal light obtained by multiplexing signal lights of different wavelengths is transmitted over an optical transmission path, said method comprising: setting numbers representing how many signal lights to be allocated consecutively in groups of consecutively allocated wavelengths on said wavelength grids; and consecutively allocating the signal lights on said wavelength grids in groups in accordance with the set numbers, wherein at least two groups have different numbers of signal lights, but not allocating a signal light on at least one wavelength of said wavelength grid adjacent to each group of consecutively allocated wavelengths on the wavelength grids, and the numbers representing how many signal lights to be allocated consecutively in groups of consecutively allocated wavelengths are smaller in a short wavelength side than in a long wavelength side of the wavelength grids wherein the numbers representing how many signal lights to be allocated consecutively in groups are set to different values corresponding to wavelength bands so that a four-wave mixing crosstalk calculated for each wavelength corresponding to said wavelength grids is equal to or less than a previously set tolerance value.