100-Gb/s hybrid multiband CAP/QAM signal transmission over a single wavelength

Hybrid multiband (HMB) CAP/QAM transmitter/receiver systems are proposed for the first time. Simulation results are provided to show the feasibility of 100 Gb Ethernet links employing a single-laser source transmitting HMB CAP-16/QAM-16, CAP-32/QAM-32, and CAP-64/QAM-64 signals. The proposed hybrid scheme has low sensitivity to directly modulated laser nonlinearities. We found that QAM receivers bring about identical jitter tolerance to ideally phase compensated CAP receivers, and QAM receivers are more practical since no phase tracking and compensation are required. Compared with the case of using a standard non phase compensated CAP receiver, the use of the modified QAM-16/32/64 receiver significantly lowers system timing jitter sensitivity in the multiband, as well as single-band case. Results also show that the use of increasing number of bands causes increased system power margin. For practical jitter conditions of ±6 ps, three HMB CAP/QAM systems with optimum band counts are identified to be capable of supporting single-laser 100 Gb/s transmission over 15-km SMF.