Multiband Reconfigurable Antenna for Wireless Applications

Abstract

Proposed work presents, compact, light-weight and low cost triband monopole reconfigurable antenna for wireless applications. The antenna offers lowest band 1.9 GHz - 2.1 GHz (UMTS), middle band operates between 2.7 GHz - 3.1 GHz (WiMAX) while the highest band operates over 4.8 GHz - 8.6 GHz (WLAN and ITS). The lowest, middle and the highest operating bands yield 10%, 13% and 51.5% bandwidth respectively. A compact size antenna within a FR4 substrate board, of area 20× 20 mm ² makes it feasible to be used within portable devices. The top view of the antenna structure comprises of a hook shaped radiating patch along with p-i-n diodes, while rectangular slot in ground plane completes the bottom view. Frequency reconfiguration using switching states of p-i-n diodes is achieved by altering the corresponding active length of the patch. Various combinations of states of diode resulting in different antenna configurations run single band, pair of dual band and triband response. To validate the proposed work, prototype of antenna is fabricated using the photolithography technology and tested. Simulated and measured return losses are in close agreement with each other. Other parameter like radiation pattern of the antenna presented is observed to be stable.