Amplified-spontaneous-emission feedback circuit with wide operating bandwidth and dynamic range

Abstract

This study proposes an amplified-spontaneous-emission feedback circuit (ASEFC) technique. The proposed technique is the first to employ signal wavelengths of an erbium-doped fiber as the input light. Consequently, the signal wavelength and dynamic range characteristics of the ASEFC were experimentally clarified. The technique demonstrated successful operation in a wide wavelength range of 1530-1560 nm, and at a low input power level of approximately −5.2 dBm. We successfully measured a small loss variation of a variable optical attenuator in a 50 km remote fiber-optic sensing configuration using the proposed ASEFC technique and achieved improved optical power resolutions of less than 0.17 mdB.