Polarisation-channel-interleaved CS-RZ transmission at 40 Gbit∕s with 0.8 bit∕s∕Hz spectral efficiency

Experimental results are reported of polarisation-channel-interleaved carrier-suppressed RZ (PCI CS-RZ) ETDM/DWDM transmission of 8 /spl times/ 40 Gbit/s over 320 km (2 /spl times/ 160 kin) NDSF, with 0.8 bit/s/Hz spectral efficiency. An average system linear Q of 6.5 at a PRBS pattern length of 2/sup 31/ - 1 and tolerance to at least 50% degradation in orthogonality are demonstrated.