A 1.3–2.08 GHz Filtering Power Divider With Bandwidth Control and High In-Band Isolation

TLDR: In this article, a varactor-based filtering power divider was proposed for reconfigurable operating frequency and bandwidth with high in-band isolation, which achieved good impedance matching and isolation for all tunable states.

Abstract: This letter proposes a varactor-based filtering power divider that allows for reconfigurable operating frequency and bandwidth with high in-band isolation. A simple but effective tuning scheme was used to attain good impedance matching and isolation for all tunable states. Experimental results show that, for input return loss $>$ 16.6 dB, the center frequency and 1 dB constant absolute bandwidth can be tuned from 1.3 to 2.08 GHz and from 70 to 130 MHz, respectively. Moreover, this work demonstrates $>$ 26 dB output isolation, $ 0.23 dB magnitude imbalance, and $ phase imbalance. Measured and simulated results are in good agreement.