毫米波高密度脉冲功率合成放大器设计

Design of a High-Density Pulse Power-Combining Amplifier for Millimeter Wave

提出一种新颖的多层结构功率合成方法,具有密度高、插入损耗小的优点。相比传统双面合成方案,该技术在同样体积内理论上可将合成路数扩展1倍,实现输出功率增长3 dB,因而非常适合应用在对功放体积、重量有严格限制的平台中。通过对该高密度功率合成电路进行理论分析与仿真优化,在8 mm波段设计了一个具有4层电路形式的2×4路功率合成放大器。无源实测结果显示,30~37 GHz频率范围内的合成效率高于91%。放大器采用8只典型输出功率16 W的GaN MMIC单片合成,按35μs脉宽、10%占空比条件进行有源测试,在34~36 GHz频率范围内得到了最小123 W的功率输出,功率增益大于14.9 dB,功率附加效率高于21.7%。

This paper gives a novel multi-layer power-combining method which has the advantages of high density and lower insertion loss.This method can theoretically double the number of power-combining paths in the same size,that is,power increases by 3 dB.Therefore it is very suitable to be used in platforms with strict restrictions on the size and weight of power amplifiers.A 2×4-channel power amplifier with four layers of power-combining circuits is designed in 8 mm band based on the theoretical analysis and simulation optimization.The passive measurement result shows that the power-combining efficiency is higher than 91%over the range of 30-37 GHz.The amplifier is composed of eight GaN MMICs with typical output power of 16 W.In the condition of 35μs pulse width and 10%duty cycle,a minimum output power of 123 W is observed,with a corresponding power gain of more than 14.9 dB and PAE better than 21.7%.