Impact of Flange Offsets in Clamped Rectangular and Clamped Circular Waveguide Measurement Methods

This paper investigates the impact of waveguide aperture misalignments, or flange offsets, on the clamped circular and clamped rectangular waveguide methods. Simulations conducted in CST Microwave Studio^® analyze the effects of these non-ideal offsets on measured S-parameters and the extracted complex relative permittivities. The results demonstrate that the clamped circular waveguide method exhibits greater resilience to flange offsets compared to the clamped rectangular waveguide method. However, both methods show larger relative errors in the estimation of the loss factor than in the dielectric constant. Experimental measurements are also performed to validate the simulation results.