ADRV9002 - RSSI with the RX used for DPD

Hi Nicolas_22,

If we inspect this diagram from the User Guide:

We see that the Rx DFE is mostly cut out from the system when DPD is used. This includes the RSSI block, meaning that when DPD is being executed on an ORx port, RSSI cannot be used via TES. In a manner of speaking the RSSI would be later in the Rx DFE than the DPD Coefficients Engine, meaning the Rx data is likely not even getting to that block.

We are not certain if the RSSI API will even be allowed to run by the Firmware on an ORx, we will discuss with the SW team and return here, but to the best of our knowledge using an ORx port disallows the RSSI block.

I hope this helps answer your questions! If you're comfortable with telling us more about your setup we can try find ways to better support your goals?

Best Regards,
Oisín.

Hi Nicolas_22,

If we inspect this diagram from the User Guide:

We see that the Rx DFE is mostly cut out from the system when DPD is used. This includes the RSSI block, meaning that when DPD is being executed on an ORx port, RSSI cannot be used via TES. In a manner of speaking the RSSI would be later in the Rx DFE than the DPD Coefficients Engine, meaning the Rx data is likely not even getting to that block.

We are not certain if the RSSI API will even be allowed to run by the Firmware on an ORx, we will discuss with the SW team and return here, but to the best of our knowledge using an ORx port disallows the RSSI block.

I hope this helps answer your questions! If you're comfortable with telling us more about your setup we can try find ways to better support your goals?

Best Regards,
Oisín.

Hi Oisin,

Thanks for your answer.

We would like to measure the transmitted power as a built in test. The RX2 is already used, so the option would be to desactivate the DPD for measuring the output power?

Regards,

Nicolas

Hi Nicolas,

If you wanted to measure output power using an External Loopback to Rx1 you would need to use the Rx1A port and use it just as a normal Rx, rather than an ORx, and deactivate DPD as you have described. You would also need to have adequate attenuation on that feedback path so as not to damage the Rx port.

Best Regards,
Oisín.