Design and development of high-power cavity bandpass filter with improved quality factor and capacitively coupled feed

This study aims at analyzing the efficiency of high-power cavity filters in fulfilling the standard communication parameters for ground transceivers. It studied BPFs (Band Pass Filters) and particularly the cavity-type by performing detailed explanation of the design process. The research summarizes important design stages, like tuning, coupling, feeding of the cavity filter and parametric optimization is also explored through numerical simulations. According to the designed calculations, the prototype is simulated with a FDTD Solver. The end physical dimensions of the filter are calculated after going through rigorous optimization to ensure it works well. The required filter parameters including bandwidth, insertion loss, return loss, and VSWR, are obtained by the screw’s adjustment, thus the filter performance is improved. The 4th-order cavity filter with 2.4 GHz center frequency, 200 MHz bandwidth, and 0.01 dB passband ripple is then optimized with an improved quality factor design which also includes disk-based capacitive coupled technology for the feeding method. Finally, the most optimized design is fabricated, and its performance is tested by vector network analyzer. The results of the fabricated single bandpass cavity filter are compared with the designed simulated ones and the given specifications have a close alignment. This paper concludes that cavity filters should be one of the key characteristics of ground transceivers since they meet the required performance characteristics, and they can be conveniently designed and implemented in the practical world.