9
Calibration
Calibration procedure is shown in Figure 11. Two
calibration tables, high mode and low mode respectively,
are required for CoolPAM, which is due to gain dierence
in each mode.
For continuous output power at the mode change points,
the input power should be adjusted according to gain
step during the mode change.
Oset Value
(dierence between rising point and falling point)
Oset value, which is the dierence between the rising
point (output power where PA mode changes from low
mode to high mode) and falling point (output power
where PA mode changes from high mode to low mode),
should be adopted to prevent system oscillation. 3 to 5
dB is recommended for Hysteresis.
Average Current and Talk Time
Probability Distribution Function implies that what is
important for longer talk time is the eciency of low
or medium power range rather than the eciency at
full power. WS1102 idle current is 14 mA and operating
current at 16 dBm is 60 mA at nominal condition.
Average current calculated with CDMA PDF is 33 mA in
urban area and 54 mA in suburban area. This PA with low
current consumption prolongs talk time by no less than
30 minutes compared to other PAs.
Average current = ∫(PDF x Current)dp
Pout
Min PWR Max PWR
High mode
TX AGC
Low mode
Rising
Falling
RisingFalling
High Mode
Low Mode
Pout
Gain
Figure 11. Calibration procedure.
Figure 12. Setting of oset between rising and falling power.
Figure 13. CDMA Power Distribution Function.
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
4.50
5.00
-50 -40 -30 -20 -10 0 10 20 30
PA Out (dBm)
CDG Urban
CDG Suburban
Conv PAM
Digitally Controlled PAM Cool PAM
0
100
200
300
500
400
600
700
PDF
CURRENT (mA)
