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by bagels 1405 days ago
Direct communication with ground stations is usually impractical for continuous communication for a couple reasons: they're over subscribed, and there aren't any stations where your satellite spends a lot of time.

Best bet is if starlink, oneweb, etc. provide a service for satellites to relay your data back.

1 comments

Yeah that is also true. The CubeSats don't spend too much time over each ground station. You can technically get around this by swapping between ground stations and enable semi continuous communication, but it would require a ton of them to work well. Also, it wouldn't work over the ocean. There isn't really a way to partner with enough ground stations to get the needed coverage while over land. I don't think there are any ground station networks out there with enough coverage for this type of thing to be constantly swapping for near constant connectivity over land. We didn't actually need amazing connectivity. We were fine with just livestreaming occasionally, but the other issues I mentioned around data speed prevented it. I think if data speeds were better you could get live video temporarily (like 15 mins).

Also, for the satellite transmission via Starlink, I don't think Starlink / OneWeb offers that yet for CubeSats (might be wrong though). I do know Iridium allows for it though. However, as I mentioned earlier in the prev comment, the data speeds might suck still (could be wrong here too) and it costs a lot of money. I do think some ground stations would have wanted money too. We didn't actually need to livestream as it was just some fun PR trick. We ended up deciding it wasn't worth it in terms of cash / effort.

As far as over subscription, it depends. If you are using a public ground station network then its an issue. If you are partnered with no public ones then it's not as big of an issue. We were thinking of private ones only because public ones would not allow this kind of thing. So over subscription just didn't even matter for us really.