Novel Compact Planar Crossover With Bandpass Response Based on Cross-Shaped Resonator

This paper presents a novel compact planar filtering crossover with two paths operating at different frequencies. Such codesign circuit is equal to one conventional crossover plus two bandpass filters, which can realize circuit miniaturization. It is designed based on a multimode cross-shaped resonator that contributes to both crossover and filtering functionalities. Moreover, the resonator is shared by the two transmission paths while they are isolated with each other. Thus, compactness is obtained. For validation, the filtering crossover is implemented with one path operating at 2 GHz and the other at 2.4 GHz. The theoretical and measured results are in good agreement.