Analog Devices ADRV9005 Reference Manual page 237

Reference Manual
DIGITAL PREDISTORTION (DPD)
amplifierType
Currently, set the PA type to ADI_ADRV9001_DPD_AMPLIFIER_DEFAULT if DPD is enabled. The default PA type refers to both the MOS and
GaN types of PA.
lutSize
Currently, the supported LUT sizes are 256 and 512. The size determines the number of entries in the DPD LUT. A more significant number of
entries provides better LUT granularity.
model
Currently, set the model to ADI_ADRV9001_DPD_MODEL_4 only. There are other models for backward compatibility with other transceivers.
Do not use them at this time. Model 4 consists of four taps (T=4), which can be described by the following equation:
3
x(n) = ψ ( d(n − l
t
t = 0
Table 97 describes the delays for each tap.
Table 97. Delays of DPD Model 4
Tap Delay of Data (k)
0 0
1 1
2 2
3 1
x(n) = ψ ( d(n) )d(n) + ψ
Based on this, rewrite the equation as:
0
− 1)
where:
ψ (|d(n)|), ψ (|d(n-1)|), ψ (|d(n-2)|) and ψ
0 1 2
Figure 218 shows the DPD model 4 tap configuration used to generate the final predistorted data x(t).
analog.com
Figure 217. TES Configuration for External Loopback with External Power Amplifier
) )d(n − k )
t t
( d(n − 1) )d(n − 1) + ψ
1
(|d(n-2)|) represent four taps, generated by the LUT.
3
Delay of Magnitude (l)
0
1
2
2
( d(n − 2) )d(n − 2) + ψ
2
ADRV9001
( d(n − 2) )d(n
3
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