Digital Processing

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Overview of Optical Fiber Communications and DSP-Based Transmission Systems

1.1    Introduction

Since the proposed “dielectric waveguides” in 1966 by Charles Kao and George Hockham of Standard Telephone Cables (STC) Ltd. in Harlow of England [1], optical fiber communication systems have used lightwaves as carriers to transmit information from one place to the other. The distance of a few meters in laboratory, to a few kilometers, to hundreds of kilometers, and now thousands of kilometers in the first decade of this century with bit rates reaching from few tens of Mb/s in late 1960s to 100 Gb/s and Tb/s at present. Tremendous progress has been made though nearly the last 50 years due to two main significant phenomena, the guiding of lightwaves ...