设计了一种用于天文台VLBI天文观测系统的超宽带低噪声放大器,并给出了仿真及测试数据。此低噪放采用了TRIQUINT公司的TGA2525型单片级联结构,为了能够调节增益的大小及平坦度,在单片级间加入了均衡和衰减电路。在2-14GHz频率范围内实现了噪声系数优于3.2d B,增益大于35d B,平坦度小于3.3d B,输入输出回波损耗小于-10d B,1d B功率压缩点输出功率大于17d Bm。 An ultra-wideband low noise amplifier designed for the Observatory’s VLBI astronomical observation system is designed and the simulation and test data are given. This low-noise amplifier uses TRIQUINT’s TGA2525 single-chip cascaded structure, in order to be able to adjust the size and flatness of the gain, the balance between the chip level and attenuation circuit. In the frequency range of 2-14GHz, the noise figure is better than 3.2d B, the gain is more than 35d B, the flatness is less than 3.3d B, the return loss of input and output is less than -10d B, and the output power of 1d B power compression point is more than 17d Bm.