Measurement of effective dielectric constant : A comparison

This paper deals with two methods and their comparison to find the effective relative permittivity of the substrate. The two methods used are resonant method and reflection method in the planar configuration. In resonant method, a microstrip patch antenna is designed using the approximate value of the relative dielectric permittivity. The resonant frequency of the designed antenna is measured and then effective relative permittivity is calculated. In the second method, the two transmission line method is used to find the relative dielectric permittivity. The comparison of the two methods shows that resonant method is more efficient at a particular frequency whereas transmission line method is suitable to find the effective dielectric constant over a range of frequencies.