A Broadband Doherty Power Amplifier Based on Continuous-Mode Technology
A Broadband Doherty Power Amplifier Based on Continuous-Mode Technology
复制标题
基于连续模式技术的宽带Doherty功率放大器
DOI：
10.1109/tmtt.2016.2623705
复制
发表时间：
2016-12-01
影响因子：
4.3
通讯作者：
Liu, Yuanan
中科院分区：
文献类型：
--
作者：
Chen, Xiaofan;Chen, Wenhua;Liu, Yuanan
提出了一种基于连续模技术（C-DPA）的新型宽带多尔蒂功率放大器。该放大器的重点是对Doherty功率放大器（DPA）结构中的谐波分量进行控制，以提高带宽和效率。在传统的DPA中，通常需要在两个晶体管之间进行谐波隔离，以防止它们在谐波频率上相互调制。然而，正如本文所述，这种隔离实际上是不必要的。相反，通过适当设计的后谐波调谐网络，允许两个晶体管在谐波频率下相互调制，可以在连续频带上创建一系列高效的DPA模式，从而实现宽带C-DPA。基于该方法，设计了一个工作频率为1.65 ~ 2.75 GHz的C-DPA实例。实测结果表明，设计的C-DPA在-6 dB功率回退时的效率为52% ~ 66%，在1.1 ghz频段的功率利用率高于1.08。此外，当使用7.5 db峰均功率比20mhz LTE信号进行仿真时，示例C-DPA在整个1.1 ghz频段线性化后，效率为46%-62%，同时保持相邻信道功率比低于-45 dBc。据我们所知，这是第一个提出的C-DPA和最先进的宽带dpa性能。
In this paper, a novel broadband Doherty power amplifier based on the continuous-mode technique (C-DPA) is proposed. The amplifier is focused on manipulating harmonic components in a Doherty power amplifier (DPA) structure to achieve improved bandwidth and efficiency. In a conventional DPA, harmonic isolation is typically required between the two transistors to prevent them from modulating each other at harmonic frequencies. However, as presented in this paper, such isolation is not actually necessary. On the contrary, by allowing the two transistors to modulate each other at harmonic frequencies with the help of a properly designed postharmonic tuning network, a series of highly efficient DPA modes can be created over a continuous frequency band, leading to a broadband C-DPA. Based on the proposed method, an example of a C-DPA working from 1.65 to 2.75 GHz was designed. According to the measured results, the designed C-DPA exhibits a 52%-66% efficiency at a -6 dB power backoff and a power utilization factor higher than 1.08 over the 1.1-GHz band. In addition, when simulated by a 7.5-dB peak-to-average power ratio 20-MHz LTE signal, the example C-DPA exhibits an efficiency of 46%-62% while maintaining an adjacent channel power ratio below -45 dBc after linearization over the full 1.1-GHz band. To the best of our knowledge, this is the first proposed C-DPA and a state-of-the-art performance for broadband DPAs.