A Birefringent Fiber 4X4 Wavelength Crossconnect,
Abstract
A general technique for making all-fiber polarization-independent birefringent wavelength division multiplexers (BWDM) was introduced at this conference last year, and a first order 1x2 multiplexer with 0.2 nm channel spacing was presented.' This technique has now been extended, using birefringent filter synthesis, to the design of a polarization-independent 4x4 wavelength crossconnect. This device has 0.78 nm channel spacing and is constructed from single-mode birefringent fibers and polarizing beam-splitters. A 4x4 wavelength crossconnect can be used to distribute 16 signals at 4 different wavelengths as shown schematically. We have introduced a new design that is inherently simpler than conventional designs, and consists of a narrow channel BWDM in series with a wide channel flattened passband BWDM. The BWDMs are made from birefringent fibers (here 1.5 m and 3.0 m lengths) at appropriate angles (here 450 and -150) between polarizing beamsplitters (PBSs). We planned to make an all-fiber crossconnect but our all-fiber polarizing beam-splitters had insufficient extinction (30 dB is desirable) so we replaced them with bulk PBSs.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1992
- Accession Number
- ADP008204
Entities
People
- Sarah Cousins
- W. J. Carlsen