Multi-resonant Planar Antennas for Various Wireless Applications

Abstract

Modern portable communication systems have experienced high market demands in recent years and the trend is likely to continue. For that reason, modern radio-frequency (RF) research groups are studying ways to diversify applications, such as digital broadcasting, data streaming, and sensing services, to create new RF markets. These services are expected to introduce some new portable devices to meet market demands. The new devices might not even be communication terminals but multimedia devices such as laptop computers, portable multimedia players (PMPs), ear sets, etc. The number of wireless services offered in multimedia devices is likely to increase. An antenna creates a channel between wireless communication systems, and the electric ground of each system affects the performance of its antenna. Designing antenna for wireless terminals of various shapes is complicated. In this dissertation, it is modeled as a simplified electronic ground for a laptop and a PMP. Among the various microwave components of wireless communication systems, an antenna plays an important role in receiving or transmitting RF signals effectively. Designing antennas for various wireless terminals becomes complicated. Not only does the size of terminal become small, but often the antenna needs to be embedded in the terminal, oftentimes. In this dissertation, various multi-resonant planar antennas for digital broadcasting and RFID applications are proposed. The work presented in this dissertation focuses on the design and implementation of wideband and multiband antennas for various environments, such as laptops, PMPs, ear sets, and non-metal objects. Wide- and multi-band planar antennas for broadcasting services on laptops or PMPs are also studied, as is a dual-band RFID tag application.