An Expansion Joint for a Millimeter Waveguide Transmission System

An expansion joint for a circular (TE/sub 01/) waveguide millimeter wave transmission system was fabricated for a 51 mm. diameter guide. The spurious mode level was measured from 50-70 GHz and found to be at least -40dB lower than the incident TE/sub 01/ level. The measured results compared favorably with an analytic prediction of a -50dB or lower spurious mode level from 40-110 GHz.