1~9 GHz超宽带温度补偿低噪声放大器的设计

A 1~9 GHz temperature compensated ultra⁃wideband low noise amplifier

超宽带低噪声放大器是可重构射频前端、宽带相控阵雷达必需的芯片,其性能直接影响系统的灵敏度.展示一款集成温度补偿有源偏置电路的超宽带低噪声放大器,该放大器采用新型温度补偿有源偏置电路,能有效地降低工作环境温度变化导致的增益波动;同时,通过带宽扩展技术提高晶体管高频增益,实现9倍频程的工作带宽.该款芯片基于0.15μm GaAs pHEMT工艺设计制造,尺寸为2 mm×1.2 mm.测试结果表明,该低噪声放大器在5 V工作电压下,功耗为125 mW;工作频率为1~9 GHz,频带内噪声系数小于1 dB,增益大于25 dB,输入输出回波损耗小于-10 dB,输出1 dB压缩点大于10 dBm;在-55~125℃工作环境下,芯片增益波动小于1 dB.

Ultra-wideband low noise amplifier is essential for reconfigurable RF front-end and wideband phased array radar,and also is a dominating influence on sensitivity of the systems.This paper demonstrates an ultra-wideband low noise amplifier with integrated temperature compensation active bias circuit.The temperature compensation active bias applying in the LNA(Low Noise Amplifier)can effectively reduce the gain fluctuation caused by variation of ambient temperature.Meanwhile,the bandwidth expansion technology is utilized to improve the high frequency gain of transistor and realize the 9-octave operating bandwidth.The proposed LNA is fabricated by using 0.15μm GaAs pHEMT technology with a dimension of 2 mm×1.2 mm.The measurement results show that the LNA has low power consumption of 125 mW with 5 V operating voltage.The operating bandwidth is 1~9 GHz with noise figure of less than 1 dB and gain of above 25 dB.The input and output return loss is less than-10 dB,and the output 1 dB compression point is above 10 dBm.Significantly,the gain fluctuation of the LNA is less than 1 dB in ambient environment of-55~125℃.