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That headline is quite misleading, as there are several re-configurable "software-defined" satellites active in orbit, each one presenting different degrees of

That headline is quite misleading, as there are several re-configurable "software-defined" satellites active in orbit, each one presenting different degrees of flexibility. Dynamic power and frequency allocation have been used since the first HTS (Viasat-1, Echostar 23...), while dynamic bandwidth allocation is also a standard design in new satellites (Viasat-2, for example). Furthermore, other satellites such as Hispasat 36W-1 already have direct radiating arrays / phase-arrays (which I am pretty sure is the core technology of EUTELSAT's Quantum). Sure, Quantum might be (one of) the first satellite that makes full use of this technology, but this is the current trend and all the big satellite comms. companies are going to launch a similar satellite in the next 1-2 years (SES-17, SpaceX Starlink, mPower...). In any case, I believe that the dynamic resource management (DRM) software (which EUTELSAT claims to have developed) will play a crucial role in all these new satellites. Given the payload flexibility, optimally configuring all these degrees of freedom will become a very very challenging task.

sova 8y ago
Configuration sounds like a nightmare but I know little about controlling satellites. Do you think this is Sophistication at the cost of Simplicity? For example, a well-known band satellite system will float in orbit reliably(?) for a long while, but if you have hardware that is trying to sync up to a satellite signal that has since been altered/shifted/changed into a totally different domain/scope, may it not risk us rendering certain hardware useless? Just a wondering.
- okl 8y ago
  Commanding/(Re-)configuration is usually done through a separate S-Band transceiver that is part of the platform/bus, not the payload.
  - shaklee3 8y ago
    Right. The configurability is entirely in the "data path", but control of that configurability is not. The control of the satellite is a separate band, bandwidth, rate, etc, called TT&C (Telemetry, Tracking, and Commanding)
  - taneq 8y ago
    So basically there's a "bootloader" which can be used to upload new "ROMs" into the payload? Sounds like a sensible way to do it.
    - marsokod 8y ago
      It is even simpler than that: you've got a computer for the platform, and another one for the payload. You send commands to the platform computer over the TT&C frequency at a few kbps. You can also update the platform OBC as well, with its bootloader then selecting which SW image to use.
sctb 8y ago
We've updated the submitted title (“UK engineers have finished building Quantum, the first software-defined satelite”) to the sub-heading from the article. It's too easy to get things wrong when editorializing! This is one reason the guidelines ask submitters not to do it. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
- deleted 8y ago
  [deleted]
- shaklee3 8y ago
  I appreciate the update. It's probably especially difficult when the title requires you to research a bunch to know if it's true or not.
- foobar1962 8y ago
  I found the title confusing too. May I suggest leaving the word "Quantum" out of the title completely. IMHO it's rather cheeky (and misleading) for the satellite manufacturers to use that name at all for something that doesn't involve quantum-mechanics-based technology.
  - davegardner 8y ago
    The word quantum has been used as a synonym for quantity since the mid-16th century. Its use as a physics term is a much more recent development, which has definitely not fully replaced the original definition yet.
    - varjag 8y ago
      Noone thinks about Renaissance use of Latin when seeing a headline about quantum satellites.
      - wyattpeak 8y ago
        Renaissance use of Latin? It's a moderately common modern English word. Did people think Quantum of Solace was about physics? As it happens I agree the title is very confusing, but I think you're overstating the point.
shaklee3 8y ago
And nowhere will you see the capacity of this satellite actually advertised. My guess is it's about 1/4 of viasat-2 or Jupiter 2, which the former is flexible. There is a trade-off between how much flexibility you really need compared to on-board processing. On one extreme you have no idea where your customers are, so you do all processing on-board. This is the quantum model, I think. This comes at a huge hit to capacity.
- portillo 8y ago
  Initially, in 2015, they were talking about ~6-7 Gbps [1] but my guess is that the current design allows for a little bit more of throughput (8 beams @ 1 GHz/beam (max. BW) x 2 bps/Hz (?) -> 16 Gbps (?)). In any case, I would say this is a technology demonstrator satellite. I think that their main innovation might be the software to optimally allocate power, bandwidth, spectrum, and pointing and shape of each beam so that throughput/revenue /"quality of service" is maximized, which might be run on the ground and then the "instructions" sent over the TT&C link to the satellite. I doubt that the spacecraft has the autonomy level required to conduct all these tasks onboard. [1] https://spacenews.com/eutelsat-esa-taking-a-quantum-leap-toward-fully-software-defined-satellite/ https://spacenews.com/eutelsat-esa-taking-a-quantum-leap-tow...
  - shaklee3 8y ago
    I would find it really hard to argue that a satellite is to demonstrate technology. Nobody in this business thought this was impossible to do, but when the satellite + ground costs ~$300M, you need a way to recoup those costs. Infinite flexibility will never make up for a lack of bandwidth, and bandwidth demand is increasing faster than satellites can keep up. I agree with you that there's no way the optimization on those things can be done on board, which means that it's likely purely the signal processing/phased array that's consuming so much power/resources that they couldn't fit more transponders to increase capacity.
    - portillo 8y ago
      I agree with you. I should have said that I think they were not looking to maximize the system throughput when designing the system, instead wanted to test this new technology. Seems the 450 kg Quantum payload has a 5.5 kW power consumption, so yeah, that phased array seems to be drawing quite a lot of power. I am curious about your thoughts on future satellite architectures since it looks like some players are betting in full flexibility by means of DRA / phased-arrays technology (SES, SpaceX, Telesat), whereas others (Viasat) seems to be betting on fixed-spot beams + flexibility in spectrum, bandwidth, and power allocations.

sova 8y ago

Configuration sounds like a nightmare but I know little about controlling satellites. Do you think this is Sophistication at the cost of Simplicity? For example, a well-known band satellite system will float in orbit reliably(?) for a long while, but if you have hardware that is trying to sync up to a satellite signal that has since been altered/shifted/changed into a totally different domain/scope, may it not risk us rendering certain hardware useless? Just a wondering.

okl 8y ago
Commanding/(Re-)configuration is usually done through a separate S-Band transceiver that is part of the platform/bus, not the payload.
- shaklee3 8y ago
  Right. The configurability is entirely in the "data path", but control of that configurability is not. The control of the satellite is a separate band, bandwidth, rate, etc, called TT&C (Telemetry, Tracking, and Commanding)
- taneq 8y ago
  So basically there's a "bootloader" which can be used to upload new "ROMs" into the payload? Sounds like a sensible way to do it.
  - marsokod 8y ago
    It is even simpler than that: you've got a computer for the platform, and another one for the payload. You send commands to the platform computer over the TT&C frequency at a few kbps. You can also update the platform OBC as well, with its bootloader then selecting which SW image to use.

sctb 8y ago

We've updated the submitted title (“UK engineers have finished building Quantum, the first software-defined satelite”) to the sub-heading from the article. It's too easy to get things wrong when editorializing! This is one reason the guidelines ask submitters not to do it. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html

deleted 8y ago
[deleted]
shaklee3 8y ago
I appreciate the update. It's probably especially difficult when the title requires you to research a bunch to know if it's true or not.
foobar1962 8y ago
I found the title confusing too. May I suggest leaving the word "Quantum" out of the title completely. IMHO it's rather cheeky (and misleading) for the satellite manufacturers to use that name at all for something that doesn't involve quantum-mechanics-based technology.
- davegardner 8y ago
  The word quantum has been used as a synonym for quantity since the mid-16th century. Its use as a physics term is a much more recent development, which has definitely not fully replaced the original definition yet.
  - varjag 8y ago
    Noone thinks about Renaissance use of Latin when seeing a headline about quantum satellites.
    - wyattpeak 8y ago
      Renaissance use of Latin? It's a moderately common modern English word. Did people think Quantum of Solace was about physics? As it happens I agree the title is very confusing, but I think you're overstating the point.

shaklee3 8y ago

And nowhere will you see the capacity of this satellite actually advertised. My guess is it's about 1/4 of viasat-2 or Jupiter 2, which the former is flexible. There is a trade-off between how much flexibility you really need compared to on-board processing. On one extreme you have no idea where your customers are, so you do all processing on-board. This is the quantum model, I think. This comes at a huge hit to capacity.

portillo 8y ago
Initially, in 2015, they were talking about ~6-7 Gbps [1] but my guess is that the current design allows for a little bit more of throughput (8 beams @ 1 GHz/beam (max. BW) x 2 bps/Hz (?) -> 16 Gbps (?)). In any case, I would say this is a technology demonstrator satellite. I think that their main innovation might be the software to optimally allocate power, bandwidth, spectrum, and pointing and shape of each beam so that throughput/revenue /"quality of service" is maximized, which might be run on the ground and then the "instructions" sent over the TT&C link to the satellite. I doubt that the spacecraft has the autonomy level required to conduct all these tasks onboard. [1] https://spacenews.com/eutelsat-esa-taking-a-quantum-leap-toward-fully-software-defined-satellite/ https://spacenews.com/eutelsat-esa-taking-a-quantum-leap-tow...
- shaklee3 8y ago
  I would find it really hard to argue that a satellite is to demonstrate technology. Nobody in this business thought this was impossible to do, but when the satellite + ground costs ~$300M, you need a way to recoup those costs. Infinite flexibility will never make up for a lack of bandwidth, and bandwidth demand is increasing faster than satellites can keep up. I agree with you that there's no way the optimization on those things can be done on board, which means that it's likely purely the signal processing/phased array that's consuming so much power/resources that they couldn't fit more transponders to increase capacity.
  - portillo 8y ago
    I agree with you. I should have said that I think they were not looking to maximize the system throughput when designing the system, instead wanted to test this new technology. Seems the 450 kg Quantum payload has a 5.5 kW power consumption, so yeah, that phased array seems to be drawing quite a lot of power. I am curious about your thoughts on future satellite architectures since it looks like some players are betting in full flexibility by means of DRA / phased-arrays technology (SES, SpaceX, Telesat), whereas others (Viasat) seems to be betting on fixed-spot beams + flexibility in spectrum, bandwidth, and power allocations.