Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for input impedance, return loss, voltage standing wave ratio and electric and magnetic fields is introduced in this paper. These parameters are given for TM 01 mode and using two different substrate
... [Show full abstract] materials RT/duroid-5880 PTFE and K-6098 Teflon/Glass. Experimental results for RT/duroid-5880 PTFE substrate are also introduced to validate the new model. Keywords: Fringing field, Curvature, effective dielectric constant and Return loss (S11), Voltage Standing Wave Ratio (VSWR), Transverse Magnetic TM 01 mode.