Fiber Optics Case Study

Chapter 1

INTRODUCTION

1.1 Introduction to Fiber Optics

An optical fiber communication system is analogous to any type of communication system in basic form, the function of any communication system to communicate the signal from the information source on the transmission medium to the destination. The demand for higher data rate transmission over the overall telecommunication networks is continuously increasing. Conventional communication systems based on coaxial cables, radio and microwave transmission etc. have limited bandwidth constraints, experience high loss and therefore can’t meet the existing and future bandwidth demands [1]. Optical fiber, due to its low loss and enormously large bandwidth has the potential to meet the present and

The system used a laser and erbium-doped fiber amplifiers (EDFAs) that permitted the light wave to maintain its shape and intensity [10]. Still the bandwidth available by fiber was under-utilized in single channel systems and the solution was found in the structure of wavelength division multiplexed (WDM) systems. Early WDM began used two wavelengths (850 nm and 1310 nm or 1310 nm and 1550 nm). In the early 1990s, WDM with 2 to 10 channels were used with channel spacing at an gap of about 400 GHz in the 1550 nm window. Dense WDM (DWDM) emerged in mid-1990s with 16 to 40 channels and spacing from 100 to 200 GHz. By the late 1990s, development in DWDM systems geared by having 64 to 160 comparable channels, very much packed at 50 or even 25 GHz intervals. Today, high performance, low loss and reliable optical fiber communication systems are broadly deployed within telecommunication networks across the world.

1.3 Main Advantages of Optical Fiber Communication

1.3.1 Large Bandwidth

Optical fibers are operated on carrier frequencies in the order of THz resulting in larger transmission bandwidth (in THz) as compared to ~500 MHz provide by co-axial cable systems.

1.3.2 Smaller Size and Weight

Copper cables have much higher sizes and larger weights than fiber optic cables. Optical fibers have very tiny diameters which are analogous to the diameter of human hair. Due to their smaller size and lesser weight, optical cables are easier to install and handle which save both the cost and