I am using the NUCLEO-WL55JC1 board to transmit LoRa 868MHz using low-power mode (14dBm). However, when I measure the signal in a noise free radio lab, the received signal power is incredibly low - has anyone encountered something similar?

[Rvan .8]

Details:

TX Power on Board: 14dBm (LP)

Omnidirectional TX antenna (on board): 2dBi

Directional RX antenna (LPDA): 4dBi

Distance: 0.5m free space with minimal interference in lab

Frequency: 868MHz

FSPL (868MHz @ 0.5m) = -25dB

Expected P_ in RX: -5dBm

Measured P_ in RX: -74dBm

If anyone has encountered something similar or knows how to boost the TX power (without using RFO_HP), please let me know, as I'm not sure that the board is actually transmitting 14dBm.

[CHick.3]

Did you find the problem? I'm having a similar issue. The received power is lower than expected.

[Tesla DeLorean]

Perhaps put a power meter directly on the SMA?

Check and/or instrument the Semtech register writing code so you can confirm what power mode the chip is using, and also the power/current limiter.

[CHick.3]

Tesla DeLorean,

Thank you for your response. It was helpful. Because of it I switched from trying to test with a modulated signal to a steady signal. I also tested with an antenna I had a datasheet for. After that the calculations for what to expect were much better.