Optischer Wellenleiterverstärker

摘要

An optical amplifier for use in a WDM transmission system has a circulator (20) two of whose ports (a, c) constitute the input and output ports of the amplifier, and to whose third port (b) is connected an optically amplifying fibre (21). Bragg grating reflectors (22) are formed at specific intervals along this fibre (21) chosen such that each WDM channel is reflected back to the circulator (20) at a distance in inverse proportion to the gain per unit length experienced by that channel in the amplifier fibre (21), whereby all channels are amplified by the amplifier to the same extent.