A direct method to design microwave amplifier

In this paper, we propose a method for designing a microwave amplifier that has multi-constraint, such as a given transducer power gain of GT,VSWRin⩽Sin0,VSWRout⩽Sout0 for input and output voltage standing wave ratios respectively, and F⩽F0 for noise figure. This method is straightforward and does not use trial and error like conventional methods. We show that there exists one optimal solution that can be obtained with this direct method, if our goal is the optimization of one of these parameters like the lowest noise figure. We introduce a new circle as Constant GT And VSWROut circle(CGAVO circle). Assuming constant GT, the relation of minimum and maximum VSWRout in terms of VSWRin, and vice versa are obtained. At the end, we discuss the choice of GT for an amplifier and its limits.