Ultra-Wideband Communications: Fundamentals and Applications

4.1. Introduction

As discussed in Chapter 1, ultra-wideband technology can deliver a large amount of data with low power spectral density (PSD) due to the modulation of extremely narrow pulses. The brief duration of UWB pulses spreads their energy across a wide range of frequencies, from near DC to several gigahertz. This spread of energy enables UWB signals to share the frequency spectrum with existing radio services and avoids expensive frequency spectrum licensing fees. Although UWB communications offers a promising solution to the problem of an increasingly overcrowded frequency spectrum, the overlay of UWB signals onto existing narrowband systems raises interference concerns for incumbent radio services. Despite the fact that UWB signals ...