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Power effiCienCy in wireless CommuniCations
V
errP
is the phase difference between the input signal and the output
signal in radians.
V
errP
= R
output
− R
input
(7.8)
Alpha and beta is the parameter used to control the amplitude and
phase of the output.
PA
Digital
Predistortion
Block
Input Phase
Output Phase
Pre-
distorted
Pre-
distorted
Complex
Multiplier
Lookup Table
(LUT) for S
(Amplitude)
Lookup Table
(LUT) for R
(Phase)
Indexing
Adaptation
Block
Output Amplitude (S)
Output Phase (R)
Amplitude
(S)
Input
Phase (R)
Predistorted
Input Phase (R)
Predistorted Input
Amplitude (S)
Update
LUT for R
Update LUT
for S
Figure 7.13 Components ...