A Four-Way Microstrip Filtering Power Divider With Frequency-Dependent Couplings

A four-way microstrip power divider is designed with bandpass filtering response. The synthesized inline filter has a generalized Chebyshev response, where frequency-dependent couplings are utilized. All of the critical parameters, including the characteristic impedances and electrical lengths, can be determined by our derived closed-form formulas. By extending the inline filter, the configuration of four-way power divider is obtained. Then, three isolation resistors are properly selected according to the even-/odd-mode analysis. The proposed four-way filtering power divider has low in-band insertion loss and high frequency selectivity. It can provide the in-band return loss and isolation between outputs better than 16.7 and 17.5 dB, respectively.