Patent ID: 7489868

Claim:
An apparatus for measuring Optical Beat Interference (OBI) noise, the apparatus being applied to a central office included in a Subcarrier Multiple Access (SCMA) optical network, the central office including an optical receiver for converting an optical signal received through an optical fiber into an electrical signal, the apparatus comprising: a power divider for dividing the power of a signal output from the optical receiver into two signals; a first filter for passing one of the two signals divided by the power divider in a low band of frequencies below a band of subcarrier signals; a second filter for passing the other of the two signals divided by the power divider in a high band of frequencies above the band of subcarrier signals; a power measurement unit for measuring power of each signal passed through the first and second filters; and a signal processor for measuring OBI noise level based on power values measured by the power measurement unit, wherein the signal processor measures OBI noise level by selecting the larger or smaller of two power values measured respectively by the first and second power meters.