4 ms·

X-band transmitters on the global marketplace

39 points by kartikkumar 7y ago

nimbius 7y ago
https://www.endurosat.com/cubesat-store/cubesat-communication-modules/x-band-transmitter/ https://www.endurosat.com/cubesat-store/cubesat-communicatio... Am i reading this correctly?? the x-band cubesat transmitter is the cost of a Telsa???
- kartikkumar 7y ago
  Everyone is focused on the precipitous drop in launch costs, but the supply chain is really where the biggest opportunities now lie. Many suppliers are struggling with finding the right balance between economies of scale, lead time, modularity/standardization, reliability, and (backwards) compatibility. As industry volume increases, this should start straightening itself out. The challenge is that there's a bit of a chicken-and-egg problem at the moment: there's a severe lack of transparency, meaning that commercial market forces are largely missing. So greater transparency = greater competitiveness = better price/value ratio = faster, better, cheaper satellites
- dfox 7y ago
  I would not be too surprised if components used in this device come out to total price range of 5k€-10k€ in one-off quantities, which paints the price in different light.
  - ohazi 7y ago
    The individual transistors that are used for the LNA and power amplifier stages of these transceivers usually sell for tens to low hundreds of dollars a piece in single unit quantities. A good design will probably use 4-10 of them, depending mostly on output power requirements. Throw in a few mixers for up/downconversion, some expensive ADCs, an FPGA, a CNCed aluminum enclosure, and you quickly end up at around $1000-$5000 in parts. There's definitely demand for these radios, but it's no consumer product, so the markup is going to be painful. There's definitely opportunity here, but it will be difficult to get the prices down significantly when there are like five semiconductor companies that are doing most of the gouging. They're very happy with their current "sell you a specialty part for $45 that costs them $2 to produce" business.
    - Reelin 7y ago
      > They're very happy with their current "sell you a specialty part for $45 that costs them $2 to produce" business. How difficult is it to design these parts and successfully fabricate them? Are they expensive simply because they're uncommon, or is the R&D process for them nontrivial?
      - extrapickles 7y ago
        The main problem is the lack of scale to spread the R&D costs over. If a part takes $1m to develop, and you only sell a few thousand of them, the part will be in the hundreds of dollars regardless of how "cheap" it is to make. QA processes also add a fair amount to the final price as each part might have several hours of individual attention by a technician to make sure it operates perfectly. Even for something as simple as a strut, they might saw every other one they make in two to inspect it for defects as doing so is vastly cheaper than having something fail in launch or orbit.
      - madengr 7y ago
        The space qualified transistors are: Hermetic ceramic and copper tungsten packages. Eutectic die attach. Hand wired bonded. X-rayed for voiding under die. Gettered to absorb hydrogen. High temperature lid soldering in helium atmosphere. Leak tested. RF-DC burned in and thermal cycled. Note the threshold voltage changes as the parts are burned in, so all these parts are aged. The PCBs are aluminum backed. Gold selectively removed from PCB traces to prevent solder embrittlement. Parts sometimes vacuum soldered to PCB (to prevent voiding). X-Rayed to look for voids. Cleaned and vacuum baked. RF-DC burn in. My stuff had the lids welded on. Vibration tested. More electrical testing and thermal cycling. Ping tested to hear for loose parts and solder balls. All this adds up the cost. Rework is a nightmare, especially after the lids are welded. All the other SMT parts are also S-level. A single tube of low-outgassing RTV (Dow 340) is $600.
    - madengr 7y ago
      I have built several X-band transmitters, both ground and space qualified. The space qualified GaAs FETs in the latter were $7k each.
- Rebelgecko 7y ago
  I don't think you can get a Tesla for $22,000 (USD). But these low volume (both in terms of # of units sold and SW&P) things get really expensive as high R&D costs are mostly amortized by people who are willing to ride the cutting edge. If you don't have high bandwidth requirements you can get away with some $20 transmitters using LORA or some cheapo ~900mhz transmitters that use amateur frequencies
  - someguydave 7y ago
    Your low-cost LORA/whatever plan would be foiled by lack of regulatory approval for using those frequencies and those waveforms.
    - mNovak 7y ago
      If they're already ISM do they need special approval to use in space?
      - someguydave 7y ago
        Yes. https://www.space.com/40001-four-cubesats-unauthorized-launch-fcc.html https://www.space.com/40001-four-cubesats-unauthorized-launc...
      - marsokod 7y ago
        The last time so checked, I could not find anything preventing the use of Lora in space (if you are operating in the UK). However, the frequencies you can use are different over different territories so it is up to your satellite to use the correct ones depending on where it is and what it is pointing at.
    - Rebelgecko 7y ago
      I'm not a radio guy so I may be missing some nuances, but in my experience that's not a problem. If you're broadcasting over the whole world, you may have trouble using 915mhz. But if your ground stations are in places where 915mhz is lightly regulated it is no big deal. I think that is the case for the entire western hemisphere. The FCC lets you do pretty much whatever you want in the neighborhood of 915mhz as long as you're not pumping out more than a couple watts. We've mentioned frequencies and transmitter power in ODAR paperwork but it hasn't been an issue (ODAR is a form that the FCC gets which is mostly there to make sure you don't litter while you're in space). Edit: Actually I looked into this and we had to a bit more paperwork than just the ODAR. The FCC also wanted to know about signal modulation and ground station locations.
- someguydave 7y ago
  How much are you willing to spend to make sure that your bespoke satellite actually has working comms?
- LatteLazy 7y ago
  If you're spending 1m usd to launch the thing, is it wise to quibble over 50k? If you buy a 25k discount model and it breaks in orbit, will your boss thank you?
- bsder 7y ago
  You are talking 100Mpbs+ data rates with error correction and decoding. ADC's are probably coming in hot at 300-400MHz. That's Virtex-class land, and for a one-off FPGA at that class it's probably $5K or so. Everything in aerospace is expensive because it has zero volume. The US DoD is always bitching about this, but it isn't willing to pony up the money to put volume behind their procurement to cause the costs to drop.
- madengr 7y ago
  Yes, and I guarantee no one is getting rich. Been there, done that.

39 points by kartikkumar 7y ago

https://www.endurosat.com/cubesat-store/cubesat-communication-modules/x-band-transmitter/ https://www.endurosat.com/cubesat-store/cubesat-communicatio... Am i reading this correctly?? the x-band cubesat transmitter is the cost of a Telsa???

kartikkumar 7y ago
Everyone is focused on the precipitous drop in launch costs, but the supply chain is really where the biggest opportunities now lie. Many suppliers are struggling with finding the right balance between economies of scale, lead time, modularity/standardization, reliability, and (backwards) compatibility. As industry volume increases, this should start straightening itself out. The challenge is that there's a bit of a chicken-and-egg problem at the moment: there's a severe lack of transparency, meaning that commercial market forces are largely missing. So greater transparency = greater competitiveness = better price/value ratio = faster, better, cheaper satellites
dfox 7y ago
I would not be too surprised if components used in this device come out to total price range of 5k€-10k€ in one-off quantities, which paints the price in different light.
- ohazi 7y ago
  The individual transistors that are used for the LNA and power amplifier stages of these transceivers usually sell for tens to low hundreds of dollars a piece in single unit quantities. A good design will probably use 4-10 of them, depending mostly on output power requirements. Throw in a few mixers for up/downconversion, some expensive ADCs, an FPGA, a CNCed aluminum enclosure, and you quickly end up at around $1000-$5000 in parts. There's definitely demand for these radios, but it's no consumer product, so the markup is going to be painful. There's definitely opportunity here, but it will be difficult to get the prices down significantly when there are like five semiconductor companies that are doing most of the gouging. They're very happy with their current "sell you a specialty part for $45 that costs them $2 to produce" business.
  - Reelin 7y ago
    > They're very happy with their current "sell you a specialty part for $45 that costs them $2 to produce" business. How difficult is it to design these parts and successfully fabricate them? Are they expensive simply because they're uncommon, or is the R&D process for them nontrivial?
    - extrapickles 7y ago
      The main problem is the lack of scale to spread the R&D costs over. If a part takes $1m to develop, and you only sell a few thousand of them, the part will be in the hundreds of dollars regardless of how "cheap" it is to make. QA processes also add a fair amount to the final price as each part might have several hours of individual attention by a technician to make sure it operates perfectly. Even for something as simple as a strut, they might saw every other one they make in two to inspect it for defects as doing so is vastly cheaper than having something fail in launch or orbit.
    - madengr 7y ago
      The space qualified transistors are: Hermetic ceramic and copper tungsten packages. Eutectic die attach. Hand wired bonded. X-rayed for voiding under die. Gettered to absorb hydrogen. High temperature lid soldering in helium atmosphere. Leak tested. RF-DC burned in and thermal cycled. Note the threshold voltage changes as the parts are burned in, so all these parts are aged. The PCBs are aluminum backed. Gold selectively removed from PCB traces to prevent solder embrittlement. Parts sometimes vacuum soldered to PCB (to prevent voiding). X-Rayed to look for voids. Cleaned and vacuum baked. RF-DC burn in. My stuff had the lids welded on. Vibration tested. More electrical testing and thermal cycling. Ping tested to hear for loose parts and solder balls. All this adds up the cost. Rework is a nightmare, especially after the lids are welded. All the other SMT parts are also S-level. A single tube of low-outgassing RTV (Dow 340) is $600.
  - madengr 7y ago
    I have built several X-band transmitters, both ground and space qualified. The space qualified GaAs FETs in the latter were $7k each.
Rebelgecko 7y ago
I don't think you can get a Tesla for $22,000 (USD). But these low volume (both in terms of # of units sold and SW&P) things get really expensive as high R&D costs are mostly amortized by people who are willing to ride the cutting edge. If you don't have high bandwidth requirements you can get away with some $20 transmitters using LORA or some cheapo ~900mhz transmitters that use amateur frequencies
- someguydave 7y ago
  Your low-cost LORA/whatever plan would be foiled by lack of regulatory approval for using those frequencies and those waveforms.
  - mNovak 7y ago
    If they're already ISM do they need special approval to use in space?
    - someguydave 7y ago
      Yes. https://www.space.com/40001-four-cubesats-unauthorized-launch-fcc.html https://www.space.com/40001-four-cubesats-unauthorized-launc...
    - marsokod 7y ago
      The last time so checked, I could not find anything preventing the use of Lora in space (if you are operating in the UK). However, the frequencies you can use are different over different territories so it is up to your satellite to use the correct ones depending on where it is and what it is pointing at.
  - Rebelgecko 7y ago
    I'm not a radio guy so I may be missing some nuances, but in my experience that's not a problem. If you're broadcasting over the whole world, you may have trouble using 915mhz. But if your ground stations are in places where 915mhz is lightly regulated it is no big deal. I think that is the case for the entire western hemisphere. The FCC lets you do pretty much whatever you want in the neighborhood of 915mhz as long as you're not pumping out more than a couple watts. We've mentioned frequencies and transmitter power in ODAR paperwork but it hasn't been an issue (ODAR is a form that the FCC gets which is mostly there to make sure you don't litter while you're in space). Edit: Actually I looked into this and we had to a bit more paperwork than just the ODAR. The FCC also wanted to know about signal modulation and ground station locations.
someguydave 7y ago
How much are you willing to spend to make sure that your bespoke satellite actually has working comms?
LatteLazy 7y ago
If you're spending 1m usd to launch the thing, is it wise to quibble over 50k? If you buy a 25k discount model and it breaks in orbit, will your boss thank you?
bsder 7y ago
You are talking 100Mpbs+ data rates with error correction and decoding. ADC's are probably coming in hot at 300-400MHz. That's Virtex-class land, and for a one-off FPGA at that class it's probably $5K or so. Everything in aerospace is expensive because it has zero volume. The US DoD is always bitching about this, but it isn't willing to pony up the money to put volume behind their procurement to cause the costs to drop.
madengr 7y ago
Yes, and I guarantee no one is getting rich. Been there, done that.