基于交错带状线3 dB电桥的大功率功放技术

High-power amplifier with offset parallel-coupled 3 dB bridges

摘要:

在现今的军用电子系统中，功率放大器起着举足轻重的作用。功率合成器件作为功率放大器的重要组成部分，需要满足高合成效率、高功率耐受能力和小型化的特性要求。基于交错耦合带状线定向耦合器，通过宽带匹配级联设计了一款8 GHz~12 GHz的四路功率合路器。测试结果显示：四路功率合路器的隔离度<-15 dB，回波损耗<-19 dB，合成效率>78.7%。基于该四路功率合成模块研制了一款X频段功率放大器，样机尺寸为52 mm×38 mm×5.5 mm，放大器在8 GHz~12 GHz的最大输出功率为52.2 dBm（40%占空比），插入损耗<1.4 dB。与传统的平面结构相比，基于这种功率合成器的结构更紧凑，合成效率更高，隔离度更好，功率耐受能力更强，适用于卫星通信、雷达和电子对抗等领域。

Abstract:

The power amplifier plays a privotal role in the military electronic systems in the present. The combiner, an important component of the RF power amplifier, needs to face the challenge of high combining efficiency, high power tolerance, wideband and miniaturization. This paper takes the width matching cascading scheme to design a 4-way power combiner in 8~12 GHz based on offset parallel-coupled cascade structure. The test result shows that the output isolation is <-15 dB, the standing wave loss is <-19 dB, and the combining efficiency is >78.7%. And the power amplifier system is developed with the size of 52 mm×38 mm×5.5 mm, based on the 4-way power combiner. The experimental results show the maximum output power is 52.2 dBm and the insert loss is <1.4 dB. Compared with the conventional microstrip coupler, this kind of power combiner is more compact, more efficient in synthesis, better in isolation, and more capable of withstanding power, which can apply to satellite communication, radar station and electronic countermeasure.