Abstract: In order to improve the ability of the power divider to suppress useless signals, on the basis of the structural characteristics of the Gysel power divider, a brief and universal idea of filtering integration is put forward. A filtering Gysel power divider is designed and realized. According to the odd- and even-mode analysis method, the circuit decomposition is carried out to obtain the odd- and even-mode equivalent circuits which can be analyzed easily. The port admittances and impedances are solved by using the admittance matrixes, and S-parameter expressions are further constructed to describe the circuit characteristics of the proposed filtering Gysel power divider. Simulations are given to verify the correctness of the theoretical analysis. The measured results show that a filtering Gysel power divider, whose amplitudes of the reflection coefficients are less than -10 dB at the core band of the fifth-generation mobile communication system and the isolation is 17.38 dB at the center frequency, is realized. This Gysel power divider also achieves a good out-of-band suppression.

Key words: Gysel power divider, filtering, odd- and even-mode analysis