British GPS system
Discussion
https://spacenews.com/bharti-enterprises-asks-isro...
Snippets from an interview with the head of Bharti Enterprises.
Service not until early 2022, so looks like a longer delay than the 4 months the Alaska article suggested, but not clear if he meant for limited service (12-18 month delay) or global service (6-8 month delay).
Reconfirm 648 satellites at 1200km, so no change to the previous phase 1 plan.
Request help from Indian space agency for user terminals, maybe this is to get costs down for that market rather than not having a viable terminal yet?
Clearly StarLink is going to be first to market now, at least in some regions, so sounds silly to say 'world's first LEO constellation'.
Snippets from an interview with the head of Bharti Enterprises.
Service not until early 2022, so looks like a longer delay than the 4 months the Alaska article suggested, but not clear if he meant for limited service (12-18 month delay) or global service (6-8 month delay).
Reconfirm 648 satellites at 1200km, so no change to the previous phase 1 plan.
Request help from Indian space agency for user terminals, maybe this is to get costs down for that market rather than not having a viable terminal yet?
Clearly StarLink is going to be first to market now, at least in some regions, so sounds silly to say 'world's first LEO constellation'.
Oh joy :/
“Having licensed OneWeb, under international treaties the UK is now legally liable for the OneWeb satellites
“If OneWeb goes bust and abandons its hardware in space, the UK is responsible for the debris.”
https://www.theneweuropean.co.uk/top-stories/uk-go...
“Having licensed OneWeb, under international treaties the UK is now legally liable for the OneWeb satellites
“If OneWeb goes bust and abandons its hardware in space, the UK is responsible for the debris.”
https://www.theneweuropean.co.uk/top-stories/uk-go...
ash73 said:
What precisely does OneWeb do?
Is this for gps / road charging, or rural internet?
I'm confused the two are being conflated.
It's for internet services, but the politicians seem to have got it into their heads that it can provide GPS, despite the satellites not being designed for that purpose and being in the wrong orbit Is this for gps / road charging, or rural internet?
I'm confused the two are being conflated.
https://spaceflightnow.com/2020/09/22/oneweb-to-re...
Flights resume in December on Soyuz rockets via Arianespace. Then finish the initial constellation on 15 or 16 more Soyuz.
Not planning to be the launch customer for Ariane 6 any more.
Commercial service for Northern Europe, Canada & Alaska by end 2021.
Flights resume in December on Soyuz rockets via Arianespace. Then finish the initial constellation on 15 or 16 more Soyuz.
Not planning to be the launch customer for Ariane 6 any more.
Commercial service for Northern Europe, Canada & Alaska by end 2021.
ash73 said:
What precisely does OneWeb do?
Is this for gps / road charging, or rural internet?
I'm confused the two are being conflated.
OneWeb phase 1 looks almost certainly to be internet only which was the original intention.Is this for gps / road charging, or rural internet?
I'm confused the two are being conflated.
Given launches start again in December, there has been no time for a redesign.
Future phases or maybe a handful of phase 1 satellites could be a test bed for low earth orbit location services to see if they are viable.
It has unfortunately become a proxy for ongoing Brexit / political skirmishes.
https://spacenews.com/oneweb-secures-additional-fi...
OneWeb gets approval for financing to restart full operations targeting a launch in December.
https://www.ispreview.co.uk/index.php/2020/10/cour...
Court approves bankruptcy sale to the UK gov, Bharti Airtel consortium.
https://insidegnss.com/oneweb-leo-pnt-progress-or-...
Good article laying out why this is unlikely to be a combined Comms and independent location services satellite constellation.
From a global usefulness view, another independent location services system doesn't add much. An LEO repeater for existing GPS, Galileo, GLONASS signals seems much more useful. I hope it goes in this direction.
OneWeb gets approval for financing to restart full operations targeting a launch in December.
https://www.ispreview.co.uk/index.php/2020/10/cour...
Court approves bankruptcy sale to the UK gov, Bharti Airtel consortium.
https://insidegnss.com/oneweb-leo-pnt-progress-or-...
Good article laying out why this is unlikely to be a combined Comms and independent location services satellite constellation.
From a global usefulness view, another independent location services system doesn't add much. An LEO repeater for existing GPS, Galileo, GLONASS signals seems much more useful. I hope it goes in this direction.
36 satellites go up tomorrow (18th Dec) on a Soyuz from Vostochny.
https://www.spacedaily.com/m/reports/Arianespace_t...
Sunil Mittal says positioning and navigation is still a goal, but for gen 2 satellites at least a couple of years away.
https://advanced-television.com/2020/12/14/oneweb-...
Also says to finish constellation will take US$2-2.5bn, Bloomberg says half to be covered by JV partners (UK gov & Airtel) unsure how much of the US$1bn put in already covers this, if any.
https://www.bloomberg.com/news/articles/2020-12-09...
South Korean firm Intellian is working on user terminals, no details given on size/cost.
https://www.capacitymedia.com/articles/3827232/one...
Hughes given contract to build more ground terminals (the ones that link the network to the internet) and parts of user terminals.
https://news.satnews.com/2020/12/16/hughes-to-driv...
https://www.spacedaily.com/m/reports/Arianespace_t...
Sunil Mittal says positioning and navigation is still a goal, but for gen 2 satellites at least a couple of years away.
https://advanced-television.com/2020/12/14/oneweb-...
Also says to finish constellation will take US$2-2.5bn, Bloomberg says half to be covered by JV partners (UK gov & Airtel) unsure how much of the US$1bn put in already covers this, if any.
https://www.bloomberg.com/news/articles/2020-12-09...
South Korean firm Intellian is working on user terminals, no details given on size/cost.
https://www.capacitymedia.com/articles/3827232/one...
Hughes given contract to build more ground terminals (the ones that link the network to the internet) and parts of user terminals.
https://news.satnews.com/2020/12/16/hughes-to-driv...
I don’t get the data aspects of this, let alone the GPS bits.
We have satellite data today - its slow, height latency and expensive. To counter this, systems like Starlink have 10s of thousands of satellites in low earth orbit - right now they have 800. Initial testing of Starlink suggest that it will be high capacity and low-ish latency. Anyone sticking small numbers of satellites into higher orbits will be hitting latency and capacity issues in short order.
IMO if SpaceX doesn’t go bust before it gets it over the line, Starlink will annihilate data revenues for every Telco on planet earth within a decade.
We have satellite data today - its slow, height latency and expensive. To counter this, systems like Starlink have 10s of thousands of satellites in low earth orbit - right now they have 800. Initial testing of Starlink suggest that it will be high capacity and low-ish latency. Anyone sticking small numbers of satellites into higher orbits will be hitting latency and capacity issues in short order.
IMO if SpaceX doesn’t go bust before it gets it over the line, Starlink will annihilate data revenues for every Telco on planet earth within a decade.
At that low altitude, dead satellites will degrade and reenter by themselves after a few months. Faulty or obsolete ones that are still responding will likely be steered downward to speed that up.
SpaceX already did that with some of their first gen Starlink sats. One of the reasons they're released at such a low level is to minimise the time dead satellites take to degrade. They're also designed to burn up and leave no sizeable parts surviving.
SpaceX already did that with some of their first gen Starlink sats. One of the reasons they're released at such a low level is to minimise the time dead satellites take to degrade. They're also designed to burn up and leave no sizeable parts surviving.
The Russians have been launching OneWeb satellites on Soyuz rockets (along with Arianespace operated Soyuz from French Guiana). 11 of the 13 launches to date have been by Russia.
Now the Russians are saying they want a guarantee that OneWeb is for civilian use only and that the British government has sold it share in the project by late Friday, Moscow time. If not, they'll remove the rocket (due from Baikonur on Saturday) from the pad and they won't launch any others either.
Neither of these conditions seems likely to happen. So OneWeb will probably have to wait for Ariane 6 to become operational later this year (maybe) before they can put up any satellites again.
Now the Russians are saying they want a guarantee that OneWeb is for civilian use only and that the British government has sold it share in the project by late Friday, Moscow time. If not, they'll remove the rocket (due from Baikonur on Saturday) from the pad and they won't launch any others either.
Neither of these conditions seems likely to happen. So OneWeb will probably have to wait for Ariane 6 to become operational later this year (maybe) before they can put up any satellites again.
OneWeb is a satellite Internet system with the global navigation system bodged on isn't it?
As for SpaceX launching them, thier mounting/dispersal system and other bits will have been designed specifically for the planned launch system so would probably need a fair bit of work to launch on something else.
As for SpaceX launching them, thier mounting/dispersal system and other bits will have been designed specifically for the planned launch system so would probably need a fair bit of work to launch on something else.
Tempest_5 said:
The Oneweb satellites are quite small. The Galileo navigational payloads are relatively big, about twice the size of a Oneweb satellite. Ok, the Galileo design is getting on a bit now but I can't see it having been miniturised.
This isn't simply a case of slapping a few extra boxes of electronic gizmos on the existing satellite designs. This will require a complete new satellite design.
Space inside satellites tends to be at a premium. You need to mount the equipment on the body panels to keep the effects of the vibration environment during launch to a minimum. Mounting things on tall brackets is a bit of a no no, it amplifies the random vibration levels. Units that dissipate lots of heat need mounting on the panels. There are ways around the heat issue for units that dissipate less heat but it involves more mass. So we have an accommodation issue.
More mass from the extra payload. You need to see if the structure is up to it. The panels may need beefing up, thicker skins, denser honeycomb core. More mass. I will explain my mass fixation later.
Even if there were space, you need to get the power from somewhere. The solar panels would have been optimised in their size selection, excess capacity means having panels that are too big panel and is excess mass.
You will need to get rid of the extra power dissipated from the extra nav payload as well. For this you need extra panel area to radiate the heat away. You might get away with less powerful amplifiers for the inter satellite links & satellite/ground links as being LEO with more satellites the distances are smaller. You will also probably want doublers and heatpipes to move the heat around. More Mass!
The On Board Data Handling System will need a redesign to take the extra telecommands/telemetry. New TT&C units and a new wiring loom design. The ground segment will need a bit of a rework in this respect too.
Having now created a satellite, say, 25% heavier we need to look at how it is mounted on the launch vehicle. Can the satellite launch racking structure support the extra mass on launch? Again it will have been optimised, (I've reviewed enough stress analysis to know the margins involved), so probably a new one of those as well. Also, now less satellites on one launch, more launches = more cost.
This is not an "off the shelf solution". No Satellite project I worked on in 18 years as a spacecraft systems engineer was ever over endowed with excess power, and on occasion getting rid of the waste heat was a bit tight. Mass was always an issue (always my fault as well, although I simply compiled the mass budget from data given to me). Oneweb isn't the simple solution its being sold as as far as I can see.
I have seen too many projects try to go for the cheap option and end up being well over budget and schedule. I don't see this being different. Maybe I'm wrong, the only details I have on Oneweb are based on a quick trawl of the internet.
We have the ability to do such a project in the UK, we build the Galileo payloads, but it won't be cheap. There has been damage to the UK space industry due to Brexit and this will continue. Doing the project in the UK could be the uplift this part of UK industry needs.
Too much technical content. Just make it work, ok?This isn't simply a case of slapping a few extra boxes of electronic gizmos on the existing satellite designs. This will require a complete new satellite design.
Space inside satellites tends to be at a premium. You need to mount the equipment on the body panels to keep the effects of the vibration environment during launch to a minimum. Mounting things on tall brackets is a bit of a no no, it amplifies the random vibration levels. Units that dissipate lots of heat need mounting on the panels. There are ways around the heat issue for units that dissipate less heat but it involves more mass. So we have an accommodation issue.
More mass from the extra payload. You need to see if the structure is up to it. The panels may need beefing up, thicker skins, denser honeycomb core. More mass. I will explain my mass fixation later.
Even if there were space, you need to get the power from somewhere. The solar panels would have been optimised in their size selection, excess capacity means having panels that are too big panel and is excess mass.
You will need to get rid of the extra power dissipated from the extra nav payload as well. For this you need extra panel area to radiate the heat away. You might get away with less powerful amplifiers for the inter satellite links & satellite/ground links as being LEO with more satellites the distances are smaller. You will also probably want doublers and heatpipes to move the heat around. More Mass!
The On Board Data Handling System will need a redesign to take the extra telecommands/telemetry. New TT&C units and a new wiring loom design. The ground segment will need a bit of a rework in this respect too.
Having now created a satellite, say, 25% heavier we need to look at how it is mounted on the launch vehicle. Can the satellite launch racking structure support the extra mass on launch? Again it will have been optimised, (I've reviewed enough stress analysis to know the margins involved), so probably a new one of those as well. Also, now less satellites on one launch, more launches = more cost.
This is not an "off the shelf solution". No Satellite project I worked on in 18 years as a spacecraft systems engineer was ever over endowed with excess power, and on occasion getting rid of the waste heat was a bit tight. Mass was always an issue (always my fault as well, although I simply compiled the mass budget from data given to me). Oneweb isn't the simple solution its being sold as as far as I can see.
I have seen too many projects try to go for the cheap option and end up being well over budget and schedule. I don't see this being different. Maybe I'm wrong, the only details I have on Oneweb are based on a quick trawl of the internet.
We have the ability to do such a project in the UK, we build the Galileo payloads, but it won't be cheap. There has been damage to the UK space industry due to Brexit and this will continue. Doing the project in the UK could be the uplift this part of UK industry needs.
Gassing Station | Science! | Top of Page | What's New | My Stuff