A Post-Matching Doherty Power Amplifier Employing Low-Order Impedance Inverters for Broadband Applications

作者：Pang, Jingzhou^*; He, Songbai; Huang, Chaoyi; Dai, Zhijiang; Peng, Jun; You, Fei

来源：IEEE Transactions on Microwave Theory and Techniques, 2015, 63(12): 4061-4071.

DOI：10.1109/TMTT.2015.2495201

• Broadband
• Doherty
• low-order impedance inverter
• low-pass filter
• post matching

This paper presents a modified Doherty configuration with extended bandwidth. The narrow band feature of the conventional Doherty amplifier is discussed in the view of the broadband matching. To extend the bandwidth, the post-matching architecture is employed in the proposed design. Meanwhile, broadband low-order impedance inverters are adopted to replace the quarter-wavelength transmission lines. Low-pass filter topologies are used to realize both the post matching network and the impedance inverters. A modified Doherty Power amplifier was designed and fabricated based on commercial GaN HEMT devices to validate the broadband characteristics of this configuration. The 6-dB backoff efficiencies of 47%-57% are obtained from 1.7 to 2.6 GHz (41.9% fractional bandwidth) and the measured maximum output power ranges from 44.9 to 46.3 dBm in the designed band. In particular, more than 40% efficiencies are measured at 10-dB backoff throughout the operation band.

• 出版日期2015-12
• 单位电子科技大学