Simple bidirectional add/drop amplifier module based on a single multiplexer

Abstract

This invention is to construct a bidirectional WDM add/drop amplifier module for transmitting WDMS in bidirection and for adding/dropping a signal in bidirection at each node in a WDM network system using a single N×N multiplexer. The bidirectional WDM add/drop amplifier module,comprises an 8×8 arrayed-waveguide grating,The 8×8 arrayed-waveguide grating,has, at each side, a WDMS input end L,or R,a WDMS output end L,or R,three separated signal input ends L,L,and L,or R,R,and R,and three separated signal output ends L,L,and L,or R,R,and R,One L,or R,of the separated signal input ends is designated as an added signal input end, one L,or R,of the separated signal output ends is designated as a dropped signal output end, and the separated signal output ends L,and L,or R,and R,except for the dropped signal output end connected to the signal input ends L,and L,or R,and R,at the same side. The WDM add/drop amplifier module,comprises a circulator,L,,R provided at both ends of 8×8 arrayed-waveguide grating,to distinguish paths of different WDMSs and to transmit through each path respectively, an unidirectional optical band pass filter,L or,R provided between the WDMS output end L,or R,of the 8×8 arrayed-waveguide grating,and the circulator,L,,R to eliminate a relative intensity noise, and a bidirectional signal amplifier,L or,R.