recently i bought some HTCC-AB02 CubeCell boards, to test the indoor range of the LoRa transceiver. Before i tested the indoor range with some other RF transceiver with a receiver sensitivity of around -113 dBm, the SX126x LoRa transceiver should have about -130…-140 dBm. So the range should be much greater than before, but it isn’t.
With a range of some meters between two HTCC-AB02 boards the RSSI is -50 and the SNR is 3 or 4. With some obstacles and around 70 meters between these boards (pingpong example from git) the RSSI shows -110 and SNR -14 or less. Then 2 meters more in range the communication isn’t possible anymore.
Why is the RSSI so bad in short distance with no obstacles and why doesn’t the RSSI goes down to -130…-140?
- 868 MHz
- 14 dBm
- SF 12
- 125 kHz
- coding rate 4/5
- preamble length 8
This article shows LoRa communications over a 12-floor building https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=8273458