Analyzing the Impact of Truncated Ground Structure on the Parameters of Fabricated Rectangular Patch Antenna

Abstract

In this work a prototype of conventional microstrip patch antennas (MPA) with rectangular patch has been practically fabricated on PTFE (Teflon) substrate (dielectric constant=2.1, loss tangent=0.0004) of 1.5mm thickness. The whole size of antenna is 30×30×1.5mm3 with patch dimensions of 20×12×0.035mm3. The antenna was energized by microstrip inset line feed. Significant parameters of antenna like Return Loss, VSWR, Bandwidth and Input Impedance was experimentally measured using Vector Network Analyzer. Furthermore the length of ground structure of the antenna was reduced to 16mm. The measurements were taken and compared with conventional RMPA. Conventional RMPA resonated at 7.5GHz at a Return Loss of -11.16dB, VSWR) of 1.77 and a -10dB Bandwidth of 174MHz (7.581GHz-7.407GHz). The same antenna with truncated ground structure (TGS) resonated at 1.93GHz giving a Return Loss of -29.44dB, Voltage Standing Wave Ratio of 1.10 and -10dB Bandwidth of 312MHz (2.116GHz-1.804GHz). The conventional RMPA may be used for C-Band applications while RMPA with TGS may be used for GSM applications. For a frequency of 1.93GHz the RMPA with TGS presented a miniaturized antenna.