Inquiry Regarding DPD Usage with Tx Data Rate Below 122.88MSPS

PaulJung said:

Is it not possible to use DPD with a data rate lower than this?

Not possible with TX IQ rate <122.88MSPS

PaulJung said:

If it is not possible to use DPD with a Tx data rate lower than 122.88MSPS, could you explain the reason to me?

DPD actuator operates at a min. rate of 491.52MSPS, and with 122.88MSPS IQ rate, enabling both DPD HB1 and DPD HB2, the actuator gets the input at 491.52MSPS.

With 61.44MSPS, enabling both HB1 and HB2 will get the signal at 245.76MSPS.

PaulJung said:

For your reference, I would like to use 61.44MSPS for a bandwidth of 50MHz.

Not possible.

Thank you for your response.

Could you advise me on what can be done with ADRV9029 to achieve DPD performance and RF performance for a signal with below 50MHz bandwidth at a TX data rate of 122.88MHz?

For example, changing the CFR pulse file to 50MHz (+/-25MHz) or modifying specific parameters of ADRV9029, etc., any of these options would be appreciated.

You need to generate the CFR pulse with 50MHz BW signal with 4x Interpolation (preferred), You can start with default DPD tracking configuration. Do a model sweep at the target power and then optimise the DPD tracking parameters with the optimised model.

Let us know if you face any issue.