Dpd Actuator Bypass - Analog Devices ADRV9029 User Manual

Preliminary Technical
Data

DPD ACTUATOR BYPASS

The ADRV9029 DPD provides a mechanism to bypass pre-distortion through GPIO control. The GPIO input is level sensitive and
activates the unity gain model for the duration of time where the GPIO level is high. The GPIO based DPD actuator bypass is
typically used for antenna calibrations in M-MIMO applications, where the pre-distortion must be disabled for the duration of
antenna calibration to prevent pre-distortion from affecting antenna calibration accuracy. Figure 32 describes how this process is
implemented.
Data from DPD
Half Band Filters
The GPIO control for DPD actuator bypass is managed by the stream processor in the transceiver. This feature can be enabled
through the following steps:
1. Configure the stream to associate a GPIO with DPD actuator bypass control and generate a stream binary. The transceiver
evaluation software can be used to configure the GPIO for DPD actuator bypass and generate the stream binary. The "Tx Ant
Cal GPIO Pin" option under Stream Settings in the initialization page can be used to configure the GPIO and the stream
binary can be generated using the "Create Script" option shown in Figure 33.
2. Convey this stream configuration to ADRV9025 software by assigning the stream GP input pins in the post MCS init
Figure 33. DPD Actuator Bypass GPIO Pin Stream Configuration Using Transceiver Evaluation Software
structure. In Figure 34 an example configuration is shown where GPIO_06 is assigned to Stream GP Input 6 in the post MCS
init structure.
DPD Actuator
Unity Gain
Model
Pre-
Distortion
Model
Figure 32. DPD Actuator Bypass through GPIO
Rev. PrA | Page 31 of 82
GPIO
ADRV9025 Stream
Processor Ctrl
1
0
DPD Actuator
Output