Insensitivity to slow changes of the birefringence of a recirculating fibre optical delay line is achieved by using a linear strand of nonpolarisation-preserving fibre in combination with a magneto-optical polarisation conjugating device. This delay line is applied to generate frequency reference markers for coherent communication systems
Published in:
Electronics Letters
(Volume:30
,
Issue:
10
)
Date of Publication: 12 May 1994