Title :
Theoretical sensitivity of direct-detection multilevel modulation formats for high spectral efficiency optical communications
Author :
Han, Yan ; Li, Guifang
Author_Institution :
Coll. of Opt. & Photonics, Central Florida Univ., Orlando, FL
Abstract :
Sensitivities of several direct-detection multilevel modulation formats, including M-ary differential phase-shift keying (M-DPSK), M-ary differential amplitude-phase-shift keying (M-DAPSK), and M-ary differential polarization-phase-shift keying (M-DPolPSK) are systematically calculated. The theory is based on a unified mathematical framework for direct-detection receivers using optical delay interferometers and balanced detectors. Results quantitatively elucidate the tradeoffs between these direct-detection multilevel modulation formats as well as the classic multilevel modulation format, M-ary amplitude-shift keying (M-ASK). Although the conventional bit error rate estimation method based on the eye Q-factor with Gaussian approximation is not accurate enough for DPSK and DQPSK, it is found to be reasonably accurate for M-DPSK with M>8 and in M-DPolPSK
Keywords :
Q-factor; amplitude shift keying; differential phase shift keying; error statistics; light interferometry; optical fibre communication; optical modulation; optical receivers; photodetectors; DPSK; DQPSK; Gaussian approximation; M-ary differential amplitude-phase-shift keying; M-ary differential phase-shift keying; M-ary differential polarization-phase-shift keying; balanced detectors; bit error rate estimation; direct-detection modulation formats; direct-detection receivers; eye Q -factor; multilevel modulation formats; optical delay interferometers; unified mathematical framework; Bit error rate; Delay; Differential phase shift keying; Interferometers; Optical fiber communication; Optical interferometry; Optical modulation; Optical polarization; Optical receivers; Optical sensors; Advanced modulation formats; amplitude-shift keying (ASK); differential amplitude-phase-shift keying (DAPSK); differential detection; differential phase-shift keying (DPSK); differential polarization-phase-shift keying (DPolPSK); optical fiber communications; phase modulation; polarization modulation;
Journal_Title :
Selected Topics in Quantum Electronics, IEEE Journal of
DOI :
10.1109/JSTQE.2006.876183
