Design of a filtering power divider with microstrip-to-slotline transition structures
A filtering power divider (FPD) with high selectivity is presented. Initially, by elaborately introducing two different types of microstrip-to-slotline transition structures and a pair of dual-mode stub-loaded resonators, dual-mode bandpass response is attained in this design. Afterwards, the resistor R is utilised to achieve high in-band isolation between two output ports of the FPD. Moreover, four transmission zeros are generated outside the passband for high selectivity performance. To validate the feasibility of the new approach, a prototype FPD operating at 3.62 GHz (f 0) is designed, fabricated and measured. Both simulated and measured results are provided in good agreement indicating that the proposed FPD exhibits a better than 20 dB isolation inside the passband and extended upper stopband up to 10 GHz.