Is that ~650mts as tested by you, or by the manufacturer? Presumably your distance is at ground level but still line-of-sight. What sort of noise would you have had in that radio band? Are we talking country fields and no other wifi or Bluetooth in sight, or are we talking of invisible battles taking place during the signal's ~650 metre expedition?We're using modules from China (aliexpress) nRF52840
100% tested with standard ceramic antenna ~650mts
just can't be used to connect direct to the phone, you need something like
your sensors - BLE log range - serial - BLE standard - Smartphone
That nRF52840 does look pretty good, though. I read this post about Nordic Semiconductor themselves doing tests with with a drone and GPS, where they got "almost 800 meters" line-of-sight using the 125 kbps long range mode. My default reality-adjustment-factor for the Scandinavian marketplace is about 20 dB higher than for for the Chinese marketplace, so I'll take those results as being true, but... the post did leave me with a couple of background niggles.
One is that they say they didn't go further because the drone pilot couldn't (legally) go beyond visual range, but... the base station receiving the GPS coordinates doesn't have to be co-located with the drone pilot, so why didn't they just move the station (or the pilot) to increase the test distance??? Like, presumably these guys are keen to see how far it will go, so why stop just as they're coming 'round the home turn?
The other is that they're suggesting that it should be possible to get to 3200 metres. Really? Nothing is impossible, but that'd be mighty impressive they did get a usable and reasonably stable link over that distance. In the meantime, I think this guy in the comments is at the head of the Queue Here For Disappointment line:
I'd be wanting some good odds on that before placing any bets.So technically with a bitrate of 125Kbps, you are telling me we can use nRF52840 boards can advertise packets up to a range of 800x4 i.e 3200 meters?