Patch-antenna miniaturization: From normal to exotic materials
Antti Karilainen, Pekka Ikonen, Olli Luukkonen, Constantin Simovski, and Sergei Tretyakov
Introduction
Antennas can be minituarized by loading them for example with dielectric substrate beneath them. The bandwith can be expanded if dielectric substrate is replaced with magnetic material, at least if the magnetic material is lossless and dispersion free. Transmission-line model can be used to calculate effect of minituarization:
Patch antenna with artificial magnetic substrate
Actual metasolenoid based artificial magnetic material doesn't have static magnetic response. This causes the dielectric substrate to actually work better than the magnetic substrate.
Meandered planar inverted-F antenna (PIFA)
Meandered planar inverted-F antenna is commonly used in mobile applications. Antenna without loading has resonance freguency f0=610 MHz.The loading substrate was placed in several positions under antenna. The benefit from loading substrate depends strongly on the position. Magnetic materials with low loss are needed to improve the performance.