Document Type
Thesis
Date of Award
1-31-1991
Degree Name
Master of Science in Electrical Engineering - (M.S.)
Department
Electrical and Computer Engineering
First Advisor
Yeheskel Bar-Ness
Second Advisor
Thomas Barnwell
Third Advisor
Haim Grebel
Abstract
We experimentally demonstrate a novel concept for recovery of a Sub-Carrier and Timing Clock in fiber-optic communication systems using a Wavelength Division Multiplexing technique. The idea is to send a low radio frequency (RF) as a reference pilot from the transmitter to the receiver on a separate laser using the principle of Wavelength Division Multiplexing (WDM). This low frequency signal is taken to be a subharmonic of the subcarrier used to carry information and intensity modulate another laser. Such approach will be expected to generate at the receiver a local oscillator in high coherence with the subcarrier.
We show that transmission of Coherent microwave signal on two different wavelengths will remain sufficiently coherent up to 100 Km or more, and experimentally demonstrate this fact for 36 Km fiber.
We believe that this concept could be very useful for subcarrier systems operating beyond 1 GHz and upto 20 GHz, where in other approaches subcarrier and timing clock recovery will be limited due to laser chirp and residual fiber dispersion. The WDM proposed approach can provide a subcarrier for coherent detection and timing clock at the receiver up to 100 Km with minimum optical power penalty. With subcarrier frequency of 20 GHz, and repeater span of 100 Km, extraction of subcarrier and timing clock by other methods will be too expensive, complicated or will require very high optical power penalty. Thus the concept proposed here will make sub-carrier based systems more attractive for transmission of analog and digital information, simple and cost-effective as compared to other very high speed time division multiplexed systems.
Recommended Citation
Gehlot, Narayan, "Novel way of sub-carrier coherent detection and clock recovery in fiber-optic communications" (1991). Theses. 2484.
https://digitalcommons.njit.edu/theses/2484
