STM32WL33CC1 – Wakeup LPAWUL/MRSUBG Failing After 10m

[SergioSI]

Hello everyone,  

I’m experiencing an issue with communication between two STM32WL33CC1 devices. I’m using one for LPAWUL wakeup receiver and the other for MRSUBG transmitter, but I noticed that beyond 10 meters, the communication starts failing.  

Setup Details:

SB1 resistor: 0Ω  

-C3 resistor: 0Ω

-Configured for +20 dBm PA  

-Test environment: tested indoors in a hallway

The communication works fine up to 10 meters, but beyond that, wakeup packets are not received reliably. 

Can everone help me solve this problem and get +/-30 stable meters?

Code LPAWUR:

https://github.com/STMicroelectronics/STM32CubeWL3/tree/main/Projects/NUCLEO-WL33CC/Demonstrations/LPAWUR/LPAWUR_WakeupRadio_Rx

Code MRSUBG:

https://github.com/STMicroelectronics/STM32CubeWL3/tree/main/Projects/NUCLEO-WL33CC/Demonstrations/MRSUBG/MRSUBG_WakeupRadio_Tx

[STTwo-32 · Accepted solution]

Hello @SergioSI 

To improve the distance between the STM32WL3 nodes, I may suggest you fit the C3=100pF and try again. The distance may improve but the distance of 30 meters seems to be a real challenge for you. We can't guarantee such a distance. 

Best Regards.

STTwo-32

[SergioSI]

Thanks for the tip!

Is it possible to communicate with the LPAWUL using only the STM32CubeMX MRSUBG/LPAWUR settings, to sending a direct message through the data buffer?

I noticed on GitHub that the CRC calculation and the concatenation of the preamble and sync word are handled separately. I’d like to simplify this process and configure everything directly through the MRSUBG settings, if possible.

I’d be grateful if you could provide an example.

[STTwo-32]

Hello @SergioSI 

This is a new question. So, please close this thread by accepting a solution using the accept as solution button. And open a new one to your new question to give it more visibility.

Best Regards.

STTwo-32

[Gwo]

What should I check to improve  if the distance is only  10 to 20 centimeters?!

firmware is   https://www.st.com/en/embedded-software/stm32cubewl3.html

hardware is NUCLEO-WL33CC1

C3=100pF

[Gwo]

May I know what is maximum distance normally achieved?