微波固态功放中闭环ALC电路设计

Design of closed⁃loop ALC circuit in microwave solid⁃state power amplifier

针对发射机输入信号动态范围大,极易造成微波放大电路输出功率不稳定的问题,文中提出了一种闭环ALC电路方法。该方法通过反馈电路控制链路增益来调节微波放大电路的输出功率。据此,该文设计了一种X波段微波放大电路:工作频率为8.15~8.35 GHz,输入功率范围为-5~+5 dBm,环境温度为-40~+60℃,输出功率大于36 dBm。经实验验证,当输入功率动态范围较大时,采用闭环ALC电路可保证微波放大电路输出功率波动不超过0.3 dB,在高低温环境下也能保证输出功率波动小于0.5 dB。

A closed-loop ALC circuit method is proposed in this paper to address the problem of unstable output power of microwave amplification circuits caused by the large dynamic range of transmitter input signals.This method adjusts the output power of the microwave amplification circuit by controlling the link gain through a feedback circuit.Based on this,this article designs an X-band microwave amplification circuit:operating frequency is 8.15~8.35 GHz,input power range is-5~+5 dBm,ambient temperature is-40~+60℃,and output power is greater than 36 dBm.Experimental verification shows that when the dynamic range of input power is large,using a closed-loop ALC circuit can ensure that the output power fluctuation of the microwave amplification circuit does not exceed 0.3 dB,and can also ensure that the output power fluctuation is less than 0.5 dB in high and low temperature environments.