Abstract
An electrical multiplexing technique, namely Absolute Polar Duty Cycle Division Multiplexing (AP-DCDM) is reported for high-speed optical fiber communication systems. It is demonstrated that 40
Gb/s (4
×
10 Gb/s) AP-DCDM system shows a clear advantage over conventional 40
Gb/s RZ-OOK with 50% duty cycle in terms of dispersion tolerance and spectral efficiency. At 40
Gb/s its tolerance to chromatic dispersion (CD) is 124
ps/nm and 194
ps/nm for the worst and the best user, respectively. These values are higher than that of 40
Gb/s RZ-OOK, which is around 100
ps/nm. The spectral efficiency, receiver sensitivity and OSNR for different number of channels are discussed. Comparison against other modulation formats namely duobinary, Non-Return-to-Zero (NRZ)-OOK and RZ-Differential Quadrature Phase-Shift Keying (RZ-DQPSK) at 40
Gb/s are made. It is shown that AP-DCDM has the best receiver sensitivity (−32
dBm) and better CD tolerance (±200
ps/nm) than NRZ-OOK and RZ-DQPSK. In reference to duobinary, AP-DCDM has better receiver sensitivity but worse dispersion tolerance.