Quality factor of switching diodes for digital modulation

A quality factor of switching diodes for digital modulation is proposed. It is defined by Q
^{^}
= √(r
1
- r
2
)
²
+ (x
1
- x
2
)
²
/√r
1
r
2
where r
1
+ jx
1
and r
2
+ jx
2
represent the diode impedances in the two switching states. It is invariant to lossless transformations and permits direct computation of the loss produced by the diode in a given switching circuit.