Analog Devices ADRV9005 Reference Manual page 239

Reference Manual
DIGITAL PREDISTORTION (DPD)
Configure the changeModelTapOrders and modelOrdersForEachTap through TES, as shown in
the default model tap configuration and d n − l
t
= 0x7F, B[2] = 0x07 and B[3] = 0x06. Note: Tap 0 and 2 are recommended to be the same. For simplicity, the GUI uses X to represent
).
preLutScale
This value, given as a fixed point U2.2 number, sets the scaling factor before searching the LUT. Set the scaling factor as 1, 1.25, 1.5, 1.75, 2,
2.25, 2.5, 2.75, 3, 3.25, 3.5, and 3.75. Scale the input signal magnitude to cover close to the full range of the LUT for better DPD performance.
If the signal input to the compander is too small, then use only part of the LUT. When the input signal is small, try different scaling factors to
increase the signal level, which might improve the DPD performance. The scaling factor can be determined according to the dBFS of the input
data peak. As an example, if the signal peak power is less than −4 dBFS, apply the scaling factor 3.5.
default value of "pre-LUT Scale" as 2, which can be further changed.
DPD/CLGC Post Initial Calibration Parameters Configuration
Configure the second set of DPD/CLGC parameters after initial calibration. It is defined by the following data structure:
typedef struct adi_adrv9001_DpdCfg
{
uint32_t numberOfSamples;
uint32_t additionalPowerScale;
uint32_t rxTxNormalizationLowerThreshold;
uint32_t rxTxNormalizationUpperThreshold;
uint32_t detectionPowerThreshold;
uint32_t detectionPeakThreshold;
uint16_t countsLessThanPowerThreshold;
uint16_t countsGreaterThanPeakThreshold;
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Figure 220 shows a customized model tap configuration, which is equivalent to B[0] = 0x07, B[1]
Figure 219. Configuring Default Model Tap Order Through TES
Figure 220. Configuring Customized Model Tap Order Through TES
ADRV9001
Figure 219 and Figure 220. Figure 219
Figure 219 and Figure 220
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