Determining complex permittivity by measuring the scattered waveform from a dielectric circular cylinder

The author describes a method of measuring complex permittivity by making use of a two-dimensional scattered wave from a dielectric circular cylinder. The far-field pattern in the plane perpendicular to the cylinder axis is examined when the dielectric is illuminated by a line-source antenna that is parallel to the axis of the cylinder. An automated measurement of the complex permittivity is compared with a computed result based on theory. When the loss factor is high, this method becomes competitive with other techniques. The complex permittivity can be determined by this method over a wide range except for the case where the dielectric loss is very small