Advanced modulation formats for fiber optic communication systems

Abstract

Choice of modulation format plays a critical role in the design and performance of fiber optic communication systems. We discuss the basic physics of electro-optic phase and amplitude modulation and derive model transfer functions for ideal and non-ideal Mach-Zehnder modulators. We describe the generation and characteristics of the standard nonreturn-to-zero (NRZ) modulation format, as well as advanced formats such as returnto-zero (RZ), carrier-suppressed RZ (CSRZ), duobinary, modified duobinary, differential phase-shift keyed (DPSK), and return-to-zero DPSK (RZ-DPSK). Finally, we discuss the relative merits of these formats with respect to a variety of system impairments.

Smart color channel allocation for visible light communication cell ID

“…We assume that the transmitter transmits the signal using on-off keying modulation or variable pulse-position modulation technique [12,13]. The VLC system transmits digital signals by controlling the ON/OFF repetition of LED or the color of transmitted light.…”

Resource allocation for multichannel broadcasting visible light communication

“…Research on VLC has been under way for several years, and it is a promising technology for the future. Various modulation techniques [3][4][5][6][7] can be applied for VLC ranging from a low to a high data rate. They can be classified as on-off keying modulation (OOKM), variable pulse-position modulation (VPM), pulse-position modulation (PPM), sub-carrier pulse-position modulation (SC-PPM), sub-carrier frequency shift keying (SC-FSK), sub-carrier phase shift keying (SC-PSK), pulse width modulation (PWM), color shift keying (CSK) and OFDM.…”