Temperature Dependence of Bandpass Filters Built of Silica-Based Post-Wall Waveguide for Millimeter-Wave Applications

Temperature dependence is shown of fifth-order Chebyshev bandpass filters (BPFs) built of silica-based post-wall waveguide for millimeter-wave applications. The measured frequency drift of the three BPFs with the center frequencies of 59 GHz, 73 GHz and 84 GHz were 10.12 ppm/°C, 9.56 ppm/°C and 11.91 ppm/°C over the temperature range of 30°C to 90°C, respectively. It is confirmed that the stability of the silica-based BPFs is superior to commercial-waveguide BPFs.