
53
Power amPlifiers in wireless CommuniCations
e MRF1806 power amplifier has quite a wide linear region,
which is shown in the AM-AM characteristic curve in Figure3.21a.
It is obvious that the gain of the power amplifier has changed
in the saturation area and the power amplifier behaves nonlinearly.
eAM-PM characteristic of a simulated power amplifier is shown
in Figure3.21b, and the nonlinear behavior is presented by a variation
of the output phase and by increasing the input power.
14
DB(|S[1,1]) (R)
Test Bed
DB(|S[2,2]) (R)
Test Bed
DB(|S[2,1]) (L)
Test Bed
13.5
20
11.9
3.75
–4.38
–12.5
–20.6
–28.8
–36.9
–45
12.5
12
11.5
11
10.5
1.93 1.95 1.97
1.99 ...