一个8GHz高功率AlGaN/GaN HEMT VCO

基于中科院微电子所的AlGaN/GaN HEMT工艺研制了一个X波段高功率混合集成压控振荡器（VCO）。电路采用源端调谐的负阻型结构，主谐振腔由开路微带和短路微带并联构成，实现高Q值设计。在偏置条件为VD=20V, VG=-1.9V, ID=150mA时，VCO在中心频率8.15 GHz处输出功率达到28 dBm，效率21%，相位噪声-85 dBc/Hz@100 KHz，-128 dBc/Hz@1 MHz。调谐电压0~5V时，调谐范围50 MHz。分析了器件闪烁噪声对GaN HEMT基振荡器相位噪声性能的主导作用。测试结果显示了AlGaN/GaN HEMT工艺在高功率低噪声微波频率源中的应用前景。

An 8 GHz high power AlGaN/GaN HEMT VCO

A high power X-band hybrid microwave integrated voltage controlled oscillator (VCO) based on AlGaN/GaN HEMT is presented. The oscillator design utilizes a common-gate negative resistance structure with open and short-circuit stub microstrip lines as the main resonator for a high Q factor. The VCO operating at 20 V drain bias and -1.9 V gate bias exhibits an output power of 28 dBm at the center frequency of 8.15 GHz with an efficiency of 21%. Phase noise is estimated to be -85 dBc/Hz at 100 kHz offset and -128 dBc/Hz at 1 MHz offset. The tuning range is more than 50 MHz. The dominating effect of GaN HEMT's flicker noise on oscillator phase noise performance has also been discussed. The measured results show great promise for AlGaN/GaN HEMT technology to be used in high power and low phase noise microwave source applications.