Bidirectional ULH transmission of 160-Gb/s full-duplex capacity over 5000 km in a fully bidirectional recirculating loop

A bidirectional transmission system with 16 10-Gb/s dense wavelength-division-multiplexing channels on 32 wavelengths is demonstrated over 5000 km (50 x 100 km) of nonzero dispersion-shifted fiber in a fully bidirectional recirculating loop, for a full-duplex capacity-distance product of 800 Tb/s (.) km. This bidirectional architecture shares the optical fiber, optical amplifiers, dispersion compensators, and dynamic gain equalizers between the two traffic directions, significantly reducing the common optical equipment costs of ultralong-haul transmission systems.