Microstrip Antennas: From Standard to Compact and Reconfigurable Designs

Microstrip antennas have a fundamental role in modern wireless communication systems due to their low profile, lightweight structure, and ease of manufacturing through standard printed-circuit processes. The final project presents successive stages of the development of microstrip antennas. It starts by covering the working principles of microstrip antennas, analyzing the half-wavelength, rectangular antenna as the basic model. Then, the Planar Inverted-F Antenna (PIFA) is discussed, explaining what improvements it provides compared to the half-wavelength one, with an emphasis on its ongoing popularity in highly widespread devices. Finally, reconfigurable microstrip antennas are addressed. It is explained how this type of antenna addresses the demand for multi-band functionality, compactness, and reconfigurable operation. The main focus is the reconfiguration of frequency through PIN diodes, although the reconfiguration of parameters and other methods are touched upon briefly.