We have been working on communicating two RAK3172 modules in P2P mode for a while.
At first we worked with 868 MHz and after 300-400 meters communication between modules was lost.
Then we decided to set the frequency to 433 MHz. We connected 433 MHz antennas with 5 dBi power to our RAK3172 modules. And then in the final test we did today, we were able to reach 400 meters in the city (the RSSI was around -115 and -120 at that moment). We couldn’t get any data after 400 meters.
The transmitter (TX) RAK3172 from the modules was located on the terrace on the top floor of the building where I was located. The receiver (RX) module was located in a car 400 meters away. This was the maximum range we were able to reach during testing.
The parameters we applied in the communication test:
double myFreq = 433000000; uint16_t sf = 12, bw = 0, cr = 0, preamble = 8, txPower = 22;
I can’t understand why the distance is so low. Are we doing something wrong, or can we communicate with the RAK3172 5 dBi antenna and the above parameters for a maximum of 400 meters?