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经过过去二到三年的发展,砷化镓微波场效应晶体管已从实验室阶段进入到实用化阶段。目前正在用作C波段和X波段低噪声放大器,振荡器方面的应用正在研究。由于砷化镓场效应晶体管是较为新型的器件,许多使用者对其性能和功用可能还不太熟悉。为了选择放大器或振荡器的工作点,有必要了解器件的特性;要确定偏置的变化对S参数和噪声系数的影响,则这种了解更为重要。例如。随着漏电流的变化,由S参数计算出来的增益在相当宽的范围内保持一峰值,这说明最佳增益并不需要临界偏
After the development of the past two to three years, GaAs microwave field effect transistors have entered the practical stage from the laboratory stage. Currently being used as C-band and X-band LNAs, oscillator applications are being studied. Since gallium arsenide field effect transistors are relatively new devices, many users may not be familiar with their performance and functionality. In order to choose the operating point of the amplifier or oscillator, it is necessary to know the characteristic of the device; This kind of understanding is more important to determine the influence of the variation of bias on S parameter and noise figure. E.g. As the leakage current changes, the gain calculated from the S-parameter maintains a peak over a fairly wide range, indicating that the optimum gain does not require a critical offset