Signal light monitoring apparatus and signal light monitoring method
AssigneeNEC Corporation
InventorTAKESHI NAKATA
Life of this patent
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Abstract
An optical filter performs filtering on input monitor light in a transmission range having a carrier frequency of each channel being measured as a center frequency. Photoelectric convertors convert the monitor light filtered by the optical filter into an electrical monitor signal, and the signal detection unit judges whether signal light is present or absent based on the electrical monitor signal. Since the optical filter performs filtering, an S/N ratio of the monitor light becomes great and the signal detection unit can more accurately judge whether signal light is present or absent even in an optically noisy environment.
Claims10
A signal light monitoring apparatus comprising:
- an optical filter configured to extract light in a band having a carrier frequency of signal light, the signal light being a measurement object, as a center frequency from input light;
- and
- a signal presence/absence judgment unit configured to judge whether a signal is present or absent based on intensity of the light extracted by the optical filter.
A signal light monitoring method for a signal light monitoring apparatus, the method comprising:
- an optical filtering step of extracting, by an optical filter, light in a band having a carrier frequency of signal light, which is a measurement object, as a center frequency from input light;
- and
- a signal presence/absence judgment step of judging, by a signal presence/absence judgment unit, whether a signal is present or absent based on intensity of the light extracted by the optical filter.
Dependencies are inferred from the claim text.