A novel direct matching network synthesis technique and its application to broadband class‐J power amplifier
A novel direct matching network synthesis technique and its application to broadband class‐J power amplifier
复制标题
DOI：
10.1002/mmce.22390
复制
发表时间：
2020-08
期刊：
影响因子：
--
通讯作者：
Maoning Zeng;Shichang Chen;Weiwei Wang;Jialin Cai;Wenhui Cao;X. Zhou;W. Chan;Gaofeng Wang
中科院分区：
文献类型：
--
作者：
Maoning Zeng;Shichang Chen;Weiwei Wang;Jialin Cai;Wenhui Cao;X. Zhou;W. Chan;Gaofeng Wang
提出了一种改进传统简化实频技术的直接匹配网络综合方法。通过直接优化预选配置中各分布元件的特性阻抗(物理宽度)和电气长度(物理长度)，与SRFT相比，该方法具有更多的设计自由度，从而增加了设计灵活性和匹配效果。为了验证其有效性，设计了一个宽带J类功率放大器(PA)，并用该方法实现了输入和输出MN。通过定义一个新的目标函数来表示实现的阻抗与最佳晶体管阻抗的接近程度，成功地实现了基波和二次谐波阻抗的同时处理。给出了这一新技术的全面方程和完整的设计步骤。用10W GaN HEMT实现的J类功率放大器在2.5~3.8 GHz频率范围内的输出功率为39.2~42.3 dBm，功率附加效率为61.8%~71.6%。使用20 MHz的LTE-A信号验证了该J类功放的线性化能力。采用数字预失真技术后，相邻沟道泄漏比水平达到了−43.8dBc左右。
A novel direct matching network (MN) synthesis method improving the conventional simplified real frequency technique (SRFT) is presented in this article. By straightforwardly optimize the characteristic impedance (physical width) and electrical length (physical length) of each distributed element in a preselected configuration, the proposed method has one more degree of design freedom by comparison with the SRFT, and therefore increases design flexibility and matching effects. To demonstrate its effectiveness, a broadband class‐J power amplifier (PA) is devised for which both the input and output MNs are realized using the proposed method. The simultaneous manipulation of fundamental and second harmonic impedances is successfully realized by defining a novel target function that indicates the degree of proximity for the realized impedances to the optimal transistor impedances. Comprehensive equations and complete design procedures of the new technique are given. The measured class‐J PA implemented for verification achieves an output power of 39.2 to 42.3 dBm and power‐added efficiency of 61.8% to 71.6% over the frequency range of 2.5 to 3.8 GHz using a 10‐W GaN HEMT. A 20‐MHz LTE‐A signal is employed to validate the linearization capability of this class‐J PA. An adjacent channel leakage ratio level around −43.8 dBc is achieved after utilizing digital predistortion technique.