摘要 |
Fiber optic cable waste is avoided by measuring amplitude oscillations of four-wave mixing products in positive-dispersion and negative-dispersion fiber optic cable to determine the lengths of a first, positive-dispersion cable segment and a second, negative-dispersion cable segment that are used to provide a specified length of fiber optic cable having a specified amount of path-average chromatic dispersion. The integrated dispersion of a positive-dispersion fiber optic cable as a function of length is measured to provide a first set of data, and the integrated dispersion of a negative-dispersion fiber optic cable as a function of length is measured to provide a second set of data. A fiber-optic cable is simultaneously fed with two optical signals, a first at wavelength lambda 1 and a second at wavelength lambda 2, and the number of sinusoidal oscillations that occur in the four-wave mixing products of the Stokes (or anti-Stokes) sideband as a function of cable length are measured. The second set of data is reflected about a line representing zero length, linearly translated by the specified length along a length axis, and then linearly translated by the specified dispersion along an integrated dispersion axis to provide a transformed second set of data. A point of intersection of the first set of data with the transformed second set of data is calculated. A length coordinate of this point of intersection represents the length of the first cable segment. A length for the second cable segment is calculated by subtracting the length of the first cable segment from the specified length.
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