Search

In this paper, we propose a scheme to design the reconfigurable filtering power divider with arbitrary operating channels based on external quality factor ($Q_{\mathbf {e}}$) control. By using an input feeding line, ${n}$ resonators, and $m$ output feeding lines, the $n^{\mathbf {th}}$ -order $m$ -way filtering power divider topology can be obtained with a simple configuration. A coupled-line output feeding structure loading with multiple PIN diodes is proposed to adjust the output $Q_{\mathbf {e}}$ values. Design theories for obtaining the desired $Q_{\mathbf {e}}$ values are provided. Then, the filtering power divider can be fully reconfigured in the states with one to $m$ operating channels. Good input matching can be achieved without using an additional reconfigurable impedance matching network in all these states, resulting in a size and loss reduction. For verification, a 2nd-order 4-way reconfigurable filtering power divider is designed, fabricated, and measured. As compared to the reported reconfigurable power dividers, the proposed design shows the merits of fully reconfigurable operating channels, favorable filtering responses, low insertion losses, high isolation, and a simple structure. [ABSTRACT FROM AUTHOR]

This paper presents a Doherty power amplifier (DPA) with reduced size and wide bandwidth by using a simplified output matching topology. In broadband DPA designs, post-matching networks are usually added after the combing node, which usually occupy large circuit sizes. However, in this design, the post-matching network is not used. Instead, two ideal transformers and specific output matching components are employed at carrier and peaking branches. Then, by rearranging the output matching components in the two branches, Norton transformation can be used and the ideal transformers can be eliminated. In this way, the impedance at the combining node is directly matched to a 50- $\Omega $ load without using a post-matching network, resulting in both compact size and wide bandwidth. For verification, a broadband DPA prototype with a very simple structure is implemented. The fabricated circuit shows a compact size. A wide bandwidth from 1.3 to 2.8 GHz (73%) is achieved with a saturated output power of 41.4–44.6 dBm. The drain efficiencies at saturation and 6-dB back-off power level are 60.1–79.1% and 41.8–61%, respectively, which are comparable to those of state-of-the-art designs. [ABSTRACT FROM AUTHOR]