与普通的没有凹栅(recessed gate)的场效应管相比,有凹栅的场效应管S参数相对功率电平的变化非常小。因此,具有凹栅的场效应管在大信号时的S参数特性能够容易地在小信号条件下通过简单的测量来决定。这些数据已被用来设计有28分贝增益和1千兆赫带宽的12千兆赫3.5瓦放大器。普通的大功率砷化镓场效应晶体管往往在大信号电平时S参数发生变化,三次交调曲线呈现有一局部下陷区,其频率响应曲线因附有寄生振荡而表现出不连续性。为了 Compared with the normal FET without a recessed gate, the S-parameter of the FET with a recessed gate changes very little with respect to the power level. Therefore, the S-parameter characteristics of a FET with a concave gate at a large signal can easily be determined by simple measurement under small signal conditions. These data have been used to design a 12 gigahertz 3.5 W amplifier with 28 dB gain and 1 gigahertz bandwidth. Common high-power gallium arsenide field-effect transistor often S parameters change at large signal level, the three intercalation curve presents a partial sag zone, the frequency response curve due to the presence of parasitic oscillations and showed discontinuities. in order to