Testing from up in the sky is complicated (especially if you don’t live in the middle of nowhere), so this is a ground propagation test, from a small hill:
Conditions:
- Tx antenna: 2 dBi vee
- Rx antenna: 3 dBi dipole
- Frequency with the lowest noise floor selected (there in an on board spectrum analyser to help you with that!)
- Tx power: 15 dBm (32 mW)
- Line of sight with the transmitter: most likely not the case. Most of the received signal was likely reflections from nearby objects.
Results:
A solid 5 Mbps stream, as long as the 3 dBi receiving antenna was kept in the same position, a few cm from the receiver. That’s one of the reasons why we are saying we didn’t have line of sight. Unfortunately the green field to the right of our mark on the map was cultivated and difficult to access.
As theory suggests, lowering bandwidth to 2 MHz let us lower transmitting power to 10 dBm (10 mW) without losing signal.
Changing frequency to ones with a higher noise floor didn’t give us those nice results, so make sure you select a good frequency before flying!