Musk says Starlink will work on boats

[Scorpius]

Originally Posted by Jon Hacking

Scorpius, before jumping in, don't you think it would be a good idea to read previous posts?

The Starlink User Terminal antenna looks vaguely like a dish, but in fact it's a phased array antenna that is steered electronically, in milliseconds, without needing to move physically. SpaceX has been using them on their drone recovery ships off the coast of Florida, so it works for some mobile units. It already has sensors to compensate for the motion of the vehicle it's mounted on, but it's unclear if the sensor system is fast enough to compensate for a small boat tossing in a seaway (although it seems to be fast enough for an RV driving). But the beam steering electronics are certainly fast enough.

Sorry about that. I know there was discussion earlier about phased array antennae but I didn't realize it was confirmed that that's what they were - and it sure looked like a dish to me.

[Davidhoy]

Originally Posted by Jon Hacking

The Starlink User Terminal antenna looks vaguely like a dish, but in fact it's a phased array antenna that is steered electronically, in milliseconds, without needing to move physically. SpaceX has been using them on their drone recovery ships off the coast of Florida, so it works for some mobile units. It already has sensors to compensate for the motion of the vehicle it's mounted on, but it's unclear if the sensor system is fast enough to compensate for a small boat tossing in a seaway (although it seems to be fast enough for an RV driving). But the beam steering electronics are certainly fast enough.

I had a unique opportunity to talk with a Starlink engineer not long ago. He could not give me details, but could answer basic yes/no questions. I posed some specific questions regarding the format of the marine/mobile version of the user terminal, and gleaning what I could I came up with the following. The antenna itself will be the essentially the same as the existing design, electrically at least. The base, motorized pointing mechanism, and mounting hardware will be beefed up and ruggedized. Not sure if the antenna will be in a dome or not - I should have asked, but somehow missed the chance. I also do not know if they are going to do anything about power consumption, though I sure hope so. At least, where most cruisers travel, melting snow off the antenna will no be a big need.

[dannc]

Originally Posted by rtoner

I have signed up for the beta. I am currently in Florida. From my understanding per the sign up is this is not mobile yet. You are limited to the location you signed up for. I figured I will in one place for the hurricane season and am hoping they open up this restriction post the beta rollout.

StarLink said the location limitation is temporary. I think they said after the Beta ends the limitation will be removed. They will not have tiered service either. They only need six more launches to get the coverage needed, and given how many rockets are launched each month, it should not take long for the constellation to be at the point that beta program ends.

Later,
Dan

[Davidhoy]

Originally Posted by dannc

StarLink said the location limitation is temporary. I think they said after the Beta ends the limitation will be removed. They will not have tiered service either. They only need six more launches to get the coverage needed, and given how many rockets are launched each month, it should not take long for the constellation to be at the point that beta program ends.

SpaceX are already loosening the location limitations, and beta testers are reporting that they can move much further from their service address and still have connectivity. Musk recently tweeted in support of this, and said that full mobility will be available by the end of 2021.

[jack4566]

Davidhoy There are no dedicated heaters in the modem. The electrical energy used to run all the RF chips puts out enough heat to melt snow. ~120W is just the normal use of the device. I believe they can also bump up the heat probably by increasing VCC supply voltage to the chips.

(There are over 800 little RF modulators! Here is a teardown)

[Davidhoy]

Originally Posted by jack4566

Davidhoy There are no dedicated heaters in the modem. The electrical energy used to run all the RF chips puts out enough heat to melt snow. ~120W is just the normal use of the device. I believe they can also bump up the heat probably by increasing VCC supply voltage to the chips.

(There are over 800 little RF modulators! Here is a teardown)

Yeah, I know they don't actually have heaters, but (as you suggest) they can control the heat generated by the circuitry to effectively do the same thing - there are a lot of ICs inside that antenna! Suffice it to say that the power control needed to melt snow, which is an actual feature of the device, will not be needed in warmer climates. I have zero interest in sailing somewhere that melting snow is necessary ;-)

[rtoner]

Originally Posted by dannc

StarLink said the location limitation is temporary. I think they said after the Beta ends the limitation will be removed. They will not have tiered service either. They only need six more launches to get the coverage needed, and given how many rockets are launched each month, it should not take long for the constellation to be at the point that beta program ends.

Later,
Dan

Nice to hear I am anxiously waiting to be fully mobile.

[Jon Hacking]

Originally Posted by rtoner

Nice to hear. I am anxiously waiting to be fully mobile.

I think many of us are.

I think the main issue for current mobility is that the initial rollout worked much like GlobalStar, where the satellite you're talking to has to be able to see (talk to) a ground station, & there aren't that many ground stations. Moving around within your "cell" (about 40 miles across?) would work fine. But if you moved from an area serviced by one ground station to an area serviced by a different ground station, the system should continue to work, although StarLink couldn't guarantee this, so they didn't say anything.

The initial birds didn't have the lasers necessary for sat-to-sat communications, so your signal couldn't hop from bird to bird before coming back down to a ground station, the way Iridium works. Iridium doesn't use lasers, but they have a full worldwide mesh with only 66 satellites & very few ground stations, because the signal can bounce between satellites, & the initial Starlink birds didn't have this capability, which is obviously necessary for the system to work mid-ocean.

I initially thought that only the first 700-ish birds didn't have the lasers, but now I think that number is higher, that they put up a few birds with laser capability after 700 so they could test them, but didn't start launching all-laser equipped birds until about 1100 (does anyone have better info here?) And the laser equipped birds are bigger & don't stack as well, so they can't get 60 of them in the nose of a Falcon9 the way they could with the originals.

They now have 1300-ish birds up, so 200-ish with laser capability. Iridium achieves a full mesh with a lot less, but I don't know the range of the lasers, & the laser equipped birds need to be spread throughout the constellation. Most launches put all of those birds into the same orbit, which saturates that orbit with laser equipped birds, but leaves other orbits without.

The birds can move to other orbits, but their engines are very weak. They're known internally as "mouse fart" engines, as that's about the amount of thrust those ion engines produce. Using the engine uses up a lot of the energy budget for the bird, so it takes a long time to reposition.

[Chotu]

Real life experience with Starlink:

https://www.theverge.com/platform/am...-spacex-review

[bcboomer]

Originally Posted by Chotu

Real life experience with Starlink:

https://www.theverge.com/platform/am...-spacex-review

He set it on the ground with his house and trees in the way and then whined about it not matching the performance of fibre optic cable.

[wingssail]

Originally Posted by bcboomer

He set it on the ground with his house and trees in the way and then whined about it not matching the performance of fibre optic cable.

I'm not sure where you think he should have put it? His trees and house are reality and that reality limits the usefulness of starlink for him.

What occurs to me about use on a boat are:

• At some point spars and rigging will be in the way of line of sight
• Apparently there are motors constantly aligning the dish to the satellite, meaning electricity usage and potential for wear.
• Number of "slots" available for ocean areas away from North America
• Ongoing cost

Not something I'll jump for in the near future.

[bcboomer]

Originally Posted by wingssail

I'm not sure where you think he should have put it? His trees and house are reality and that reality limits the usefulness of starlink for him.

What occurs to me about use on a boat are:

• At some point spars and rigging will be in the way of line of sight
• Apparently there are motors constantly aligning the dish to the satellite, meaning electricity usage and potential for wear.
• Number of "slots" available for ocean areas away from North America
• Ongoing cost

Not something I'll jump for in the near future.

Well to start with they recommend the roof.

My Starlink dish is surrounded by masts and in the past 24 hours has been obstructed for 13 seconds.

No the motor only engages during the initial setup, then it focuses electronically.

Availability will improve.

[Scorpius]

Originally Posted by wingssail

I'm not sure where you think he should have put it? His trees and house are reality and that reality limits the usefulness of starlink for him.

What occurs to me about use on a boat are:

• At some point spars and rigging will be in the way of line of sight
• Apparently there are motors constantly aligning the dish to the satellite, meaning electricity usage and potential for wear.
• Number of "slots" available for ocean areas away from North America
• Ongoing cost

Not something I'll jump for in the near future.

I expect it will get much, much better as there are more and more satellites put into the constellation so that there is a much, much better chance there will be a satellite nearly directly overhead and the system will not need to search for satellites closer to the horizon which may be obstructed.

I think a lot of the current geo restrictions are due to a lack of ground stations.

[Moontide]

Fred, when I can get one for the boat it will not be permanently installed so rigging will not be an issue (except when the boat swings) and then I will just move it over a few feet.



All the Youtube I've seen makes it look like the motors really on have to move when it is initially set up. The phased array antenna eliminates the need for constant movement as with current satellite systems.


The slot issue is only due to the limited number of satellites and being a beta system. In the future the capacity will be a non-issue, except maybe for people who "abuse" the system usage.


I can tell you that I can't wait. Bought a BTC sim card here in the Bahamas and out of the last 3 weeks the system was down in at least most of the Exumas and Raggeds. I will gladly live with a few interruptions during the day. Much better than a 2 week interperuption. Of course the Alive cell system didn't have that issue so I just happened to choose the wrong cell provider.


Love the 43's from Dreyfus/NOM

[bcboomer]

Mine has 3 masts of adjacent boats in the way and it was only down for 13 seconds in the last 24 hours.
When on the hook I would only expect to use it a couple of times a day for emails etc. The power draw is about 72 watts.