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Every amplifier regardless its technology or topology contains noise sources. Some topologies are better than others. Once you have made the design, the amplifier has a minimum noise figure, most simulators are able to perform this measurement (ADS, MWO, Ansoft designer, ...). The minimum noise figure is obtained when the source impedance equals a certain value. Then you design you input matching network so that the actual source impedance is transformed into this optimum value. That's more or less the global story.
The electronic design is important but remember that the mechanical design in microwave or near frequencies is very important too.
One thing very important is that in semiconductors the working temperature is proportional to the noise generated.
I had hard to find problems in 10Gz band with noise and solved them only changing the mechanical design.Change the case , change the earth connections and put elements that heat as far away as I could.