Compact Planar Multiband Antennas for Mobile Applications

This chapter focuses on the design of compact planar multiband antennas intended for exist‐ ing wireless services including LTE, GPS, GSM, PCS, DCS, GPS, UMTS, WLAN and Wi‐ MAX bands. The present techniques available in the open literature include the modification of the main radiator via bending, folding, meandering and wrapping. Each approach offers different advantages, depending on the required application. The constraint for the lower band generation is the main challenge in radiator miniaturization. The quarter wavelength radiator that is subjected to miniaturization may suffer from limited bandwidth and low ra‐ diation efficiency. An alternative approach which relies on modifications to the ground plane is a promising technique, which often has been previously overlooked by antenna de‐ signers. The introduction of a ground slot in a finite antenna ground plane can be further extended to include reconfigurable features. Thus, such antennas that are compact and have multiband capability can be promising candidates for many wireless applications.