The Art and Science of Ultrawideband Antennas

Generally [UWB element antennas] are characterized by linear polarization, low directivity and relatively limited bandwidth unless either end loading or distributed loading techniques are employed, in which case bandwidth is increased at the expense of radiation efficiency.
IEEE Spread Spectrum Conference, 1996
The main limiting factor of a UWB system is the antenna, which acts as a filter and limits the transmission bandwidth.
Government Report, 2000
Traditionally, antenna's bandwidth has been the main bottleneck of a ultra-wide-band wireless system.
IEEE International Symposium on Antennas and Propagation, 2004
There is a widespread and continuing, erroneous impression that UWB antennas represent a fundamental impediment to the performance of a UWB radio system. In fact, there are a wide variety of UWB antenna designs with excellent 3:1 or better bandwidth performance well suited for modern 3.1 10.6 GHz systems. Unless system architects have unreasonable expectations for antenna size and form factor, the designs presented throughout this book, and particularly in this chapter, will not disappoint.
The aim of this chapter is to provide a thorough survey of the UWB antenna kingdom. This taxonomy begins by considering some of the important classes of UWB antennas including frequency-independent antennas, small-element antennas (both electric and magnetic), electrically small antennas, UWB antenna arrays, horn antennas, and reflector antennas. Within each class, this taxonomy discusses the important families of antennas and presents representative examples of particular antenna species. Given the number of designs considered in this chapter, discussion is necessarily brief. The reader is welcome and encouraged to...