A Rectangular Annular Slotted Frequency Reconfigurable Patch Antenna

摘要

A low-profile annular slotted microstrip antenna having frequency reconfigurable characteristics along with circular polarization has been described here. The antenna consists of FR-4 substrates of 48 mm × 44 mm with dielectric constant 4.4. A rectangular patch of 26 mm × 20 mm acts as a radiator. The proposed structure gives multi bands at 5.5, 6.5, 8.8, 9.7, 12.1, and 14 GHz. The proposed reconfigurable antenna shows switching involving multiple working bands at 2.1-2.2, 5.4-5.6, 10.8, 11.7, and 12.1 GHz with different diode configurations. Microstrip line feed technique is applied for excitation. This type of device can be used in spectrum management cognitive radio application.