Millimeter wave measurements of some low-loss dielectric plates by a novel cut-off circular waveguide method

An easy-to-treatment technique is proposed to measure low-loss dielectric plates by a cut-off circular waveguide method in millimeter wave region. The fringe effect can be corrected simply using correction charts calculated from the rigorous analysis based on Ritz-Galerkin method. Some low-loss dielectric plates were measured by this method to find out proper material for millimeter wave applications. It is found that modified polyolefin has an excellent electric characteristic ofμ_r=2.31 and tan δ=1.3×10^-4, which is similar to PTFE.