Communication with a weather balloon

Fuck that xbee cheap crap. It's only good really for a couple hundred meters. Do your self a favor and have it communicate through on off keying on a cheap handheld radio. Those a re rebuilt for long range and will give you a decent data rate of few kilobaud

And from my understanding the XBee can't be used alongside arduino sensors, otherwise I'd just so that.

Would I be able to connect an arduino to a raspberry pi so it can use that to communicate, and then have all the sensors attached to the rpi?

>>1167213
Even if it had long range antennas? Or is that not possible?

I was thinking of doing something like that but wasn't sure if possible. Do you have anything off the top of your head that I should look up to do that? If not I'll look it up tomorrow

>>1167215
Long range antenna = directional antenna.
Is it ok that you need to know where the balloon is?

I would look into ubiquiti airmax equipment. Built for wireless isps, good pricepoint. Easy to deploy for point-to-point IP links.

>>1167211
Sounds like there are a couple of people with good ideas here. For my own $0.02, I would suggest checking in to LiFi. That is, data sent over a laser beam.

I built a simple LiFi setup once and was able to transmit/receive stereo CD quality audio. I'm thinking set the laser transmitter up on the baloon and have the photodetector receiver on the ground. It shouldn't take too much optical power, maybe 5mW. Protip though, if you can use a telescope lens setup to expand the laser beam it will be a little easier to detect, but will require a little more optical power. Probably an 808nm IR led laser would be cheap and good. You can put a filter in front of the receiver to block noise from visible light, but any lens system on the laser output will require lenses designed for ir.

I have done a bunch of these balloon flights, so the following is experience.

I have not tried XBee, but do not rule it out. Whilst some take the datasheet as gospel, you have to consider the context they are written for. I have designed and flown modules using <10mW ERP and have not missed a single gga sentence on flights (albeit with a low baud rate). Why? You have a superb line of sight between balloon and ground station. The datasheets for modules like Xbee and NTX2 (which I used on my first few flights) have a range on the datasheet of a couple of hundred meters only because the manufacturer think your gonna be using them through a bunch of walls, streets, etc etc. No such issue with balloons.

As for antennas, don't overthink it. I started out by making a 1/4 wavelength monopole with some radials and picked it up no problem. During one flight the module actually flipped upside down (so antenna pointing up) and I didn't miss a single sentence again. In fact, I only realised something happened after watching some video. So take fancy antennas with a pinch of salt.

I would suggest checking out HabHub - it's a big community of people who are doing this nearly every day. In fact, they have a very nice to use tracker, which allows other hams to receive position telemetry and upload it for you - that way if you lose tracking when you're chasing it for whatever reason, you'll still get updated. They also have an irc which is good for extra help.

I would say having a yagi for when you are recovering the balloon would be useful though, as you are fighting the terrain you are on.

What rasp pi sensor board are you looking at using? Chances are it is compatible with the arduino, might just not have a perfect form factor.

Furthermore... You might want to look into LoRa, which is a long range low power platform for iot stuff. I know of at least one guy who has had a "chain" of nodes flying at the same time, acting as a network.

Lifi would be mega hard to do because the balloon shakes a lot. Even with some crazy good gimble, I just son't see how it is worthwhile (not saying impossible) trying to spend much time trying to get the precision and accuracy of such a setup. Try hitting a photodetector 40km away with a laser pen. Then imagine you're in 200mph winds.

>>1167279
>>1167282

Wow thanks dude, this is a lot of info. I'll do some research as to what's best for us tomorrow, and get everyone else's opinion. I really appreciate it anon

No worries. Keep us updated, sounds like a pretty cool project.

APRS

>>1167721
This. Also UHF

I've tested 900 MHz XBee stuff, standard quarter wave dipole. Gets out to about a kilometer line-of-sight.