C-band polarisation orthogonality preservation in 5Gb/s, 50µm multimode fibre links up to 3km

Abstract

We have investigated the polarisation-maintenance capability of 50microm graded-index multimode fibres (MMF) in the Cband. Using both circularly, and linearly polarisation-multiplexed signals centre-launched into the MMF, we found that orthogonality is sufficiently maintained in both cases to yield typically 10dB optical isolation between the channels.Using orthogonally circular polarisationmultiplexed signals, we show experimentally that two 3 and 5Gb/s data channels may be transmitted error free over 50microm multimode fibre spans up to 3km in length.