Miniaturization of ultra-wideband antennas invited paper

Ultra-wideband (UWB) has become the promising wireless technology in commercial applications such as short-range high-data-rate wireless communication, high-resolution imaging, and high-accuracy radar. The antenna is one of the key designs in UWB wireless systems. This paper starts with a brief introduction of particular design challenges of UWB antennas, followed by state-of-the-art solutions. Next, the miniaturization technologies for UWB antennas are addressed. Planar designs are highlighted due to their unique merits and wide adoption in practical applications. A newly developed technique to achieve the less-ground-plane-effect performance of UWB antennas, one of the most challenging issues in small antenna designs, is addressed. A design is exemplified to elaborate the mechanism of the method. Based on this concept, an antenna with further reduced size is designed to fit wireless USB dongles. Furthermore, an innovative compact diversity UWB antenna shows the advantage of the ground-plane-independence of small antennas in diversity applications. In the end, the trends of UWB antenna R&D are discussed, correlated with applications and market demands.