Abstract:
In this paper, a Left Sided Feed Microstrip Antenna (LSFMA) embedded with Defected Ground Structures (DGS) of shapes O, H and U for Industrial Scientific and Medical (ISM) band applications has been proposed. The antenna is designed with an FR4 substrate having a dielectric constant εr of 4.4 with a thickness of 1.6 mm, a dielectric loss tangent tan (δ) of 0.02 and a lande G factor of 2. The radiating patch dimensions of 38 mm x 27.6 mm are the same for the microstrip patch antenna (MSPA) without the DGS, the ‘O’ shaped and the ‘H’ shaped DGS, whereas dimensions for the U-shaped DGS are 40.5 mm x 27.6 mm. The patch thickness (t) = 0.009 mm, realizes a good impedance matching, improved gain and bandwidth, a steady radiation pattern and a constant group delay at 2.4 GHz. For the LSFMA configuration, a gain of 0.52 dB and bandwidth of 70 MHz have been reported. Three different shapes of DGS such as O, H, and U are used in the ground plane of the MSPA to observe the various effects on radiation characteristics in the ISM band. LSFMAs with different DGS are used to improve the antenna gain, return loss, VSWR and bandwidth at 2.4 GHz frequency for ISM band applications. The proposed LSFMA with different DGS are fabricated and the experimental results are verified in an anechoic chamber of millimeter wave and antenna lab. It is found that the experimental results match the simulated results.