Method and apparatus for analyzing the characteristics of an optical circuit

摘要

This invention relates to a method and an apparatus for the measurement of amplified spontaneous emission (ASE) noise of an erbium-doped fiber amplifier in the presence of an optical signal. The known technique to perform ASE measurement at the actual signal wave length is called pulse-recovery technique. The disclosed technique requires two highly blocking optical switches for the incident and the outgoing laser beams of the amplifier having a short switching time and switching both beams synchronously with high accuracy. An inventive method comprises a first step in which a first optical signal is supplied to said optical circuit via means for blocking and in which second optical signal, generated by said optical circuit, is supplied to at least one means for analyzing said second signal via said means for blocking and a second step in which said first optical signal is blocked by said means for blocking and in which said second optical signal is still supplied to said means for analyzing said second signal via said means for blocking.