A Dual-Band Dual-Output Filtering Power Amplifier Based on High-Selectivity Filtering Impedance Transformer

Abstract

In this brief, a novel filtering impedance transformer with good selectivity and high termination impedance is proposed, of which close-formed design equations are derived and effectively verified. Then, a dual-band dual-output filtering power amplifier (PA) operating at 2.4-2.6 GHz and 3.4-3.6 GHz is designed based on the proposed filtering impedance transformer. The dual-band filtering PA contains a diplexer-like output matching network, which can separate two band signals into corresponding output branches. EM-simulated results of the diplexer-like output matching network show that the isolation between the two output ports is better than 30.7 dB. Finally, for demonstration, the dual-band dual-output filtering PA using a packaged 10 W transistor is fabricated, and the measured drain efficiencies are 45.3%-50.2% and 41.7%-53.2% at lower and higher bands, respectively. Also, a good dual-band filtering response is obtained. A good agreement between simulated and measured results is observed.

Dual‐band bandpass‐filtering high‐efficiency power amplifier with second harmonic suppression

“…The proposed PA have one more bandpass‐filtering responses than the PAs in Zhuang et al 2 and Li et al, 3 and there is no filtering characteristics for the dual‐band PA in Gilasgar et al 8 Compared to the PA in Dong et al, 11 the design parameters of the OMN can be calculated using analytical formulas instead of parametric sweep simulation and numerical optimization. Moreover, comparing with the reported PAs in Zhao et al and Dong et al, 10,11 and Zhen et al, 12 dual‐band second harmonic suppressions of the PA in this work at both f 1 and f 2 are achieved and the efficiency performance is improved to some extent.…”

“…A novel dual‐band highly efficient PA with the dual‐band filtering response is presented, 10 but the efficiency at one band is only 47%. Furthermore, the harmonic suppression of the dual‐band bandpass‐filtering PA is not concerned 9–12 …”

“…Furthermore, the harmonic suppression of the dual-band bandpass-filtering PA is not concerned. [9][10][11][12] In this study, a circuit topology of dual-band bandpass-filtering high-efficiency PA with second harmonic suppression is proposed. A dual-function dual-band impedance control network (DBICN) and a novel dual-band bandpass-filtering impedance transformer (DBBFIT) are exploited in the OMN of PA to realize second harmonic suppression and excellent dual-band filtering response.…”