基于GaN器件的连续型高效宽带功率放大器设计

Design of Continuous Broadband Power Amplifier with High Efficiency Based on GaN Device

提出一种高效宽带功率放大器的设计方法,并基于Ga N HEMT器件CGH40010F设计了验证电路。利用功放管输出寄生参数的等效网络,将基于连续型功放理论得到的负载阻抗转换到封装参考面上,并利用多谐波双向牵引技术对转换后的负载阻抗进行适当调整,使二次谐波负载阻抗位于高效率区以及基频负载阻抗能够获得高功率附加效率和高输出功率。谐波阻抗位于高效率区使得匹配网络的设计简化为基频匹配网络的设计,降低了对谐波阻抗匹配的难度和宽带匹配网络设计的复杂度。实验结果表明:在1GHz^3GHz工作频带(相对带宽100%)内,功率附加效率在53%~64.6%之间,输出功率为39.5±2d Bm,增益为11.5±2d B,二次谐波小于-15d Bc,三次谐波小于-25d Bc。

A design method of broadband power amplifier( PA) with high efficiency is presented and a test circuit is designed using Ga N HEMT device CGH40010 F. Based on the approximated equivalent network of output parasitics,the load impedances obtained by continuous PA theory are transferred into the package plane,and rectified appropriately by multi-harmonic bilateral-pull technology,in order to make second harmonic load impedances in high efficient region as well as the fundamental load impedance with high PAE and output power. Harmonic impedances in high efficient region makes matching simplified into fundamental frequency matching network design,which reduces the difficulty of harmonic impedances matching and the complexity of matching network design. Measured results show that: across 1 ~ 3 GHz( 100% relative bandwidth),the test circuit is able to obtain 50% ~ 65% PAE with 11. 5 ± 2d B power gain and delivers 39. 5 ± 2d Bm output power,with second harmonic distortion less than- 15 d Bc and third harmonic distortion less than- 25 d Bc.