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In general a balanced system will lead to higher dynamic range as defined by system noise figure minus system input IP3. In a balanced system, the individual device noise figures and input IP3 values are distributed as equally as possible. For instance, using the Dynamic Range plot, the following is an example of a well balanced system:
The first item on the x-axis which is labelled "System" is the system noise figure (red) and system IIP3 (blue). This example shows relatively low noise figure and high IIP3. A bisector line between the system NF and system IIP3 (red dashed line) is drawn. The y-axis value of this bisector line is the average of system NF and system IIP3. Distributing the individual device excess noise referred to the input and device IIP3 referred to the input such that the bisector line goes through the midpoint of these two values leads to a balanced system.
The same system, but with the attenuator settings at different values is shown here:
This system configuration shows higher system noise figure and lower system IIP3, that is worse dynamic range. See how the individual noise and IP3 referred to the input do not evenly straddle the bisector line. This is an indication of a system that is not very well balanced.
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