Dpd Configuration - Analog Devices ADRV9001 User Manual

Preliminary Technical Data
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Figure 144 shows an example ACPR performance before and after DPD. The blue curve represents the ACPR performance before DPD,
from which, spectral regrowth could be observed. The black curve represents the ACPR performance after DPD. It is obvious that the
ACPR performance is significantly improved.
Satisfactory DPD performance also depends on successful completion some operations inside the device such as ADC and DAC
calibrations. Most of those operations are guaranteed internally in the device but the following operations are user configurable. It is
important to perform all those optional operations to achieve the optimal DPD performance.
Time alignment between transmit x(t) and loopback y(t) for data capture (as shown in Figure 55)
•
• Tx closed loop gain control (CLGC) tracking calibration (not available in the current release)
• Tx LOL calibration
Tx and Rx QEC calibration
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Note that DPD could only support slow frequency hopping mode.

DPD CONFIGURATION

To use the integrated DPD properly and ensure optimal performance, user needs to configure DPD parameters properly. This could be
done through ADRV9001 Transceiver Evaluation Software (TES) or Software Development Kit (SDK). The configuration consists of 2
sets of DPD parameters. The first set of DPD parameters is "pre initial calibration" parameters since they should be configured before
performing initial calibration when the device is at the "STANDBY" state. The second set of DPD parameters is "post initial calibration"
parameters since they should be configured after performing initial calibration when the device is at the "CALIBRATED" state. These
DPD parameters will be explained in details in the next two subsections.
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Figure 143. Raw Transmit Signal Input vs. Linearized Power Amplifier Output
Figure 144. ACPR Performance Before and After DPD
Rev. PrA | Page 165 of 253
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