RSSI units extracted from RAK7244C

LPWAN Developer Gateways / Concentrators RAK7244
1

I would like to know if someone could help me settle a doubt that I have about the displayed RSSI units extracted from Chirpstack running on a Rakwireless Wisgate 7244C (that uses the Semtech sx1301 chip). According to the sx1301 datasheet (top of table in page 17) we find that RSSI values are displayed in dB (link: Salesforce). On the other hand on the documentation for the packet forwarder of the sx1301 the RSSI is defined in dBm (line 144 in packet_forwarder/PROTOCOL.TXT at master · Lora-net/packet_forwarder · GitHub).

What are units displayed in Chirpstack (dB or dBm)?
Thanks in advance for your help…

2

Can’t speak about ChirpStack, however I am pretty sure that RSSI is measured in dBm.

For reference:

dB - a relative unit of measure which has no physical value (power, current, etc.). Simply put how many times something is larger or smaller in value.

dBm - this is a measurement unit for power, in this case it is the logarithmic scale unit for power related to one mW.

Thus RSSI can’t be in dB, it has to be in dBm.

In summary simply put if you measure something that has a phisical quantity, actual value it can’t be dB, it has to be dBm, dBW, dBi, dBd, etc.

Does this make sense, I hope I explained it simply enough?

Regards