Design of a New Capacitive Load Cross-Coupled Cavity Filter

This paper presents a new design method for capacitor-loaded cross-coupled cavity filter, which significantly increases the power capacity of filter while improving out-of-band rejection. The uses coaxial resonator at open end donut capacitive-load. A triangular form structure is used full-cavity arrangement to reduce size filter. In order validate design, with center frequency 2.08 GHz and bandwidth 80 MHz was designed, processed, tested. measured insertion loss ≤0.97 dB, return >20 dB in range 2040 2120 MHz; rejection as high in-band ripple 0.06 upper lower stopband-range, only 30 away from sideband. After simulation model using HFSS software (HFSS 2021, Canonsburg, PA, USA), results matched results, verified correctness practicality design. Compared ordinary-disc-load resonant cavity, capacitively loaded cavity-bandpass-filter has 13.2% reduction height 29.7% increase capacity.