A Frequency Reconfigurable Antenna with slotted ground plane for Multi-band Applications

A multi-band frequency reconfigurable slot antenna for wireless applications is proposed in this paper. The antenna consists of rectangular patch on the top. A U-shaped slot with short ends, L-shaped slot with open ends, and another U-shaped slot inside the L-slot are etched on the ground plane. To avoid cross polarization, another L-slot and U-slot inside the L-slot are introduced symmetrically. Three PIN diodes are inserted inside the U-slot and two L-slots to achieve the concept of reconfigurability in frequency. The proposed antenna can switch between two triple band modes (2.7/7/8.3 and 3/7.8/9.5 GHz), two dual band modes (3/6.8 and 6.2/8.4 GHz) and two single band modes (6.2 and 7.3GHz). The total size of the antenna is 27 ×25 mm². A dipole like radiation pattern is observed at lower frequency bands in most of the states. The maximum gain of 6.5 dB is obtained.