Recent Progress in Reconfigurable Multi-band Antennas for Switchable and Fixed-Service Laptop Wireless Applications

Reconfigurable antennas have been developed to cover various services including (GSM/DCS/UMTS/IMT-2000/WLAN). These potential services cover seven different frequency bands (800 MHz, 900 MHz, 1.8 GHz, 2.1 GHz, 2.4 GHz WLAN, and 5.2 GHz frequency bands)-- and more to come. Developed antennas are compact and should have low profiles especially for laptop implementation. Previously developed antennas (by our group) included a mini-maze, and a mini-nested antenna structures and were reconfigured using MEMS, Here, we will focus on a recently developed one; a twin-folded dipole structure. It utilizes two-branches, and each branch has more than one-resonance. The twin dipole antennas are switchable to provide wider range of operating frequencies, i.e. services. The embedded switches, however, are strategically located next to the ground plane to ease their implementation, and reduce parasitics. The implemented design is described here in detail, and is aimed at simultaneously providing fixed services like Bluetooth at 2.4 GHz, and switchable services (like GSM or PCS for example) at all other frequencies.