求助:关于小信号参数和大信号参数的区别
请教下大家小信号和大信号的定义?
ADS中,小信号参数和大信号参数的区别?
区分大小信号的关键是看功率,通常以0dBm为分水岭,小于它的信号称之为小信号,大于它的信号称之为大信号,小信号参数一般是是做LNA用,而大信号参数一般是在做PA时用,这是个人愚见,希望大家讨论。
谢谢fenghong小编
但是我想了解它们的具体含义或比较准确的定义
微波器件在小信号时,被认为工作在线性状态,是一个线性网络; 在大信号工作时,被认为工作在非线性状态,是一个非线性网络。通常采用S 参数分析线性网络,谐波平衡法分析非线性网络。
the so called small-signal analysis is a linear analysis, that means it assumes that (around a fixed dc bias point) the circuit can be regarded as sufficient linear. Therefore, all the mentioned parameters - gain, transconductance, Rin, Rout,... - also are linear small signal parameters. As soon as the signals are so large that the assumption of linearity is not true anymore, you cannot speak about voltage gain, output impedance,.....
In this case, it is important what you are interested in: waveforms, distortion, amplitudes, power consumption,....
大约明白点了
哦,原理如此!