Uniaxial Dielectric Waveguide Filter Design Accounting for Losses Using Mode Matching Technique

Dielectric filters can provide compact solutions for filter design problems. However, most dielectrics exhibit uniaxial properties, as well as, losses that will undoubtedly affect performance if not accounted for. This paper derives dispersion relations for lossy uniaxial media in dielectric waveguides and also accounts for lossy conducting walls. The waveguide discontinuity problem in the presence of lossy uniaxial media and finite conductivity waveguide walls, is calculated by mode matching technique and the results are applied to a Ka band filter. The design specifications for the proposed filter are a 32.5 GHz center frequency with 6%. Good agreement between simulated and measured results are shown.