为了解决传统宽带Doherty 放大器主辅功放管子的非理想连接及其在高频性能恶化的问题,提出了基于半集总π型阻抗变换器的改进型Doherty 合成方案。分析并给出设计参数的计算公式,仿真结果表明:1. 4 GHz~2. 6 GHz 的宽带Doherty 放大器,相对带宽达60%,峰值输出功率44. 8 dBm, 输出功率回退6 dB 漏极效率44%-49%,增益大于11 dB,带内起伏0. 6 dB,三阶互调优于-18. 5 dBc。结果证明可明显提高宽带Doherty 的带宽及其工作频率,在未来有重要工程应用价值。

In order to solve the problems that non-ideal connection between the main and auxiliary amplifiers of traditional Doherty amplifier and its performance deterioration in high frequency application, in this paper, based on the π type of semilumped transformer and modified Doherty synthetic solution. The calculation formulas of design parameters are analyzed and given. The design of 1. 4 to 2. 6 GHz broadband Doherty amplifier, relative bandwidth is 60%, the peak power output 44. 8 dBm. When output power back-off 6 dB drain efficiency 44%-49%, gain greater than 11 dB, with a ripple of 0. 6 dB, third-order intermodulation is better than -18. 5 dBc. The results show that the bandwidth and working frequency of wideband Doherty can be significantly improved, which has important engineering application value in the future.

TN722.75