伝送用空孔アシストファイバの大A_(eff)ぼ化に関する検討

摘要

ネットワークトラフィックは増大し続けており，伝送用光ファイバの大容量化に関する検討が行われている．空孔アシストファイバ（HAF）は，コア周囲に設けられた空孔により，従来のファイバに比べ曲げ損失特性やファイバヒューズ耐性に優れており，大コア径伝送路としての使用も期待できる．本報告では，ITU-T G655に準拠する伝送用HAFの実効断面積（A_(eff)ぶ拡大限界に関して検討を行った．空孔の大きさや配置，およびコアパラメータを最適化することで，A_(eff)を240μm~2程度まで拡大できることを明らかにしている．%Because of rapid network traffic increase, high capacity optical fibers for next-generation transmission are highly required. Hole-assisted fibers (HAFs) have several advantages such as low bending loss characteristics and high fiber fuse threshold as compared with conventional fibers. Therefore HAF is expected to be a good candidate for large effective area (A_(eff) transmission fibers. In this work, we investigate the limit of A_(eff) enlargement in HAFs which are compliant with ITU-T G655. It is shown that A_(eff) of HAF can be enlarged to 240 μm~2 by designing air-hole size and position as well as Ge-doped core region appropriately.