Why do we need GSM?
There are several ways to communicate with a flying copter, like a radio telemetry, Wi-Fi, or GSM. Actually, all of them are different kinds of a radio, but with it’s own characteristics, like frequency, range and bandwidth. In our UAV project we need to transfer a huge amount of data on a long distance. And, yes, the Wi-Fi is a very good choice, because it can work on the long distance, but I don’t think it will work beyond visual line of sight. GSM could, but I wasn’t sure, that it will work on a height about 60-70 meters as well as on the ground, so I’ve checked it.
Experiment
We are using iRZ RL01w router, because it has 4G and Wi-Fi in a one case and without this case it’s lightweight. I’ve tested this router with the two famous Russian mobile operators MTS and MegaFon. The experiment occurs in a small town. There was iperf client of copter and server, exposed on our office machine.
Here is the plots of result:
Conclusion
It’s ain’t much but it’s honest work
Yes, you’re absolutely right. It’s not representative example, because the small altitude, the network coverage and the another things, which could affect the bandwidth, but I hope I’ll provide more interesting data soon. Till this moment, I can definitely say, that under 70 meters, bandwidth doesn’t severely decreases.