Triple Band E-shaped Microstrip Antenna

The triple frequency design of E-shaped Microstrip antenna backed by E-shaped ground plane is proposed. The pair of rectangular slots that realizes E-shaped structure in patch as well as the ground plane reduces the resonance frequencies of TM02 and TM12 modes and along with fundamental TM10 mode yields triple frequency response. At each frequency, proposed antenna yields 1 to 2% of VSWR bandwidth. The slots in ground plane and patch modify the surface current distribution at higher order modes to give broadside radiation pattern at each frequency. To increase the gain suspended variation of defected ground plane backed radiating patch is proposed which gives more than 1 to 5 dBi of gain at each frequency. The proposed works clearly explains the functioning of defected ground plane triple band antenna in terms of patch resonant modes. This will be useful as similar work to get an insight into functioning of defected ground plane backed antenna is not available in the literature.