Recently, high-speed bimodal transmission over 1300-nm optimized single-mode fiber (1300SM) was reported using low-cost 800-nm lasers.1 This system used a short section of 800-nm optimized single-mode fiber (800SM) at the receiver to attenuate the LP11 mode. However, interference arising from cross-coupling between the LP11 and LP01 modes at a misaligned joint may result in system degradation. The system may suffer from modal noise if a short 1300SM jumper is present between two misaligned joints. The joint between the 800-nm filter and 1300SM has an intrinsic mismatch loss and is also more sensitive to transverse offsets than that of two 1300SMs.
© 1988 Optical Society of AmericaPDF Article