A 20 Msymbol/s, 64 and 128 QAM coherent signal has been successfully transmitted over 525 km using heterodyne detection with a frequency-stabilised fibre laser and an offset-locking technique. Error-free transmission (7 bit/symbol) has been achieved.
No takes yet. Share an insight, caveat, or question.
Nakazawa et al. (2006) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: