Zigbee RSSI is lower when PA/LNA is activated

RE: Zigbee RSSI is lower when PA/LNA is activated

Marjeris Romero — Thu, 02 Apr 2020 12:06:41 GMT

Hi,

If you enable PA/LNA in Softdevice it will only take effect when the radio is running BLE. The nRF 802.15.4 driver has it's own API to manage frontend modules, see: https://infocenter.nordicsemi.com/topic/sdk_tz_v4.0.0/group__nrf__802154__frontend.html

But I am not sure anyone has tested using both at the same time. I recommend you try out and use an oscilloscope of logic analyzator to trace the PA/LNA pins to make sure they are enabled for both protocols.

Best regards,

Marjeris

RE: Zigbee RSSI is lower when PA/LNA is activated

sjf — Fri, 27 Mar 2020 21:47:13 GMT

Hi msromero,

But what else needs to be configured for Zigbee?

I thought that Softdevice was the only one that needs this extra configuration. Is that true?

Thanks

RE: Zigbee RSSI is lower when PA/LNA is activated

Marjeris Romero — Mon, 23 Mar 2020 12:53:39 GMT

Hi,

Can you try using an oscilloscope or a logic analyzator to trace the PA/LNA pins in evaluation board? Are you able to see if the LNA is actually enabled or not when you set its state in the code?

Looking at the source code in the datasheet it looks like pa_lna_init() doesn't seem to configure the LNA/PA pins for Zigbee, only for the Softdevice.