Determining the complex permittivity of materials with the Waveguide-Cutoff method.

A new method for the determination of complex permittivity values is explained. The Waveguide-Cutoff method consists of a rectangular chamber with loop antennas for excitation from a Vector Network Analyzer. It then utilizes a particle swarm optimization routine to determine Debye parameters for a given material within the sample. The system is compared to a common Open-Ended Coaxial Probe technique and found to have similar accuracy for determining the dielectric constant over the same frequency band. This syste, however, does not suffer from the same restrictions as the coaxial probe and has a much larger bandwidth than other transmission line methods of similar size.