In this paper, we present a novel 3rd filtering power divider with high in-band isolation. The proposed device employs six quarter-wavelength resonators and six internal isolation resistors symmetrically arranged to require the power division and filtering function. Based on the circuit topology, the multiple resistors can be integrated to obtain a good isolation and port impedance matching. Compared to the conventional power divider with bandpass response, the new device is easy to realize a high-order design with a good isolation. For demonstration, a prototype operating at 1.5 GHz with more than 20 dB in-band isolation is implemented. Simulated and experimental results agree well, validating the proposed methodologies.
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