Abstract
A comparison method is presented for measurement of dielectric constant of semiconductor at microwave frequencies. The semiconductor sample partially loads one of the waveguide channels. The transmission through the above channel is compared with another similar but unloaded waveguide channel using magic tee. The propagation coefficient in semiconductor loaded waveguide is related to complex dielectric constant of semiconductor sample using a variational integral. Some curves are presented to obtain value of dielectric constant graphically at X-band frequencies. Finally, some experimental and theoretical results are compared.