CHAPTER 1
INTRODUCTION
“Wideband” is referred to as a wide operating range of frequencies in microwave engineering, and its relevant technique was initially developed and applied for military communication in the past few decades. In recent years since 2000, unlicensed usage of ultra-wideband (UWB) spectrum has been progressively released globally for short-range wireless communications. It stimulates much interest in exploration of various wideband or UWB techniques for civil applications. As compared with traditional narrow-band communication, wideband or UWB communication has a doubled or extremely wide operating bandwidth so as to bring out its unique feature in enabling high-speed data transfer for short-range wireless connections as well as applications in low data rate, radar, and imaging systems.
Tracking the history of UWB, wireless communication via electromagnetic wave began with transmission and reception of a time-domain pulse signal in an ultra- or very-wide frequency range more than 100 years ago. In 1886, Heinrich Hertz proofed the Maxwell equations via experimental realization of a spark gap transmission, and in 1895, Guglielmo Marconi built up the first radio commutation system in his laboratory in Italy. As a key building block in this wireless system, the antenna was invented and constructed by inducing the radiation through a spark from a metal plate. One year later, with the joint effort of Marconi and William Preece who was the chief telegraph engineer in ...
