Ryan McLinko answers questions about satellite communications and space systems, covering mesh networks in low-Earth orbit, radiation shielding for commercial processors, and cost trade-offs between many small satellites versus one large satellite.
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My question is around communication. So right now we are in Wi-Fi, and I've been reading quite a bit about mesh networks. So communication in space, are there alternate researches going on for creating a mesh for communication inside the space?
So mesh networks are sometimes used in space. So for example, I showed those satellites where you had lots of potential internet connectivity. Service, putting lots of satellites in lower orbit. So the issue with lower orbit is that it's very low, meaning that if you have a satellite that's here— we'll do the 2D version— satellite that's here or satellite that's here, there's no way for you to talk to you because there's the Earth in the way. So what we'll oftentimes— and similarly, let's say that you've got a user here and you've got a ground station terminalized internet here. Say you do have a satellite that's here, great. But that satellite can't see the ground station, so it cannot provide real-time internet connectivity. So the way that a lot of these companies will solve this is that they have more satellites here and here, and they create a mesh. And so it's basically just going through a loop of different satellites. Does that answer your question?
Yes. So my interest in space, for more than space reasons, is it's pushing the boundaries of technology. And the same technology can be translated into consumer goods right now. So yeah, my passion is designing things for consumers. So are there any good resources where you can look at the latest research going on in this area for space?
That's a good question. I think— so from a— I guess it depends on what areas you're looking at. If you're looking at it from electronics areas, probably not a huge amount. But I think your best bet to try to figure out what's being used and what's the new and latest and greatest is to look at— either do the sort of things that I mentioned when you're looking for a company to join or a company to start, which is to go and look at what's out there currently, find out what companies are doing what, which areas of those you're interested in, looking at news articles, conferences, anything like that, and then using that to create kind of this link deep link search, getting you to— that will get you to articles, will get you to descriptions, will get you to people that you can talk to about a particular topic that is specifically what you're interested in.
Most of the research is not public.
That's true.
And being a small fry, being someone who's starting out with a startup, yes, I feel extremely under-resourced as an engineer.
Yeah, it is certainly especially true for Space-related stuff. A lot of that is because of these regulations, the ITAR and EAR-type regulations that make it so that things can't be made public that would— might otherwise be made public in other industries. So that certainly makes it tough. But there is some that was put out there. Oh, one thing that might be helpful is to look specifically at university research. A lot of universities have aerosol labs.
Okay.
And by necessity, by definition, that stuff is all clear in regulation. It's also public because it's people that write theses. There's actually a lot of useful information in people that are writing theses and projects that labs are doing, things like that. That might be your best actual resource. Thank you.
So earlier you were talking about using non-traditional components in satellites to reduce cost. Is it possible to use processors with, like, say, the power of, like, a computer or a phone if you use correct shielding, or does that not exist or is it crackable?
That is another one of the possibilities, yes. In fact, there are— there's kind of a few things at play. One of them is actually that as your process size, the distance, the size of your transistors goes down, that actually gives you advantages with radiation because the charges are smaller. Basically, you have smaller little capacitors. Which means that it's harder to cause destructive events, and they will be what are called single-event upsets, which means that they are transitory errors. Transitory errors are fine as long as you have the software to go through and correct them, and certainly if you have a powerful computer, you have the ability to run those sorts of checks and fixes. Similarly, putting something in a big box is also a viable strategy, especially at geostationary orbit. You're mostly looking at electron forces. Which means that you can shield that out because electrons are smaller, less momentum, with shielding much more easily. So those are all strategies that— and certainly, and also how you build the circuit around your component, things like that are all viable strategies that putting in a more powerful computer or FPGAs are also a technology that is very good for radiation. They're all things that you can do.
Okay. And I had a second question. Do you know— do you have an approximation of the amount of money saved when using a data center array approach compared to a big satellite?
It's going to depend. But it depends very widely on the specific application. But just to try to put it in some sort of perspective or put some sort of numbers to it, electronics are going to be your biggest enemies when you're dealing with Making something absolutely work or whatever, although you see this with other things, with mechanisms and anything else as well. But you have the potential for the highest savings to be these $200,000 chips down to $20 chips, or boards like an avionics board or something that costs $4 million that would otherwise cost $1,000 or less. So you have things like this that it depends on what fraction of your system or what different types of components, whereas if you have, say, If you're buying machine components, there's not going to be nearly as much of a cost savings. So depending on what sort of breakdown of your bill of materials will determine what that cost savings can be by taking a more component— each component being riskier approach. OK.
So you can build a bunch of cheaper satellites instead of one very expensive satellite.
Right. And then the other side of it is, if you're familiar with electronics, but you're buying these components, but you're buying boards. It's like when you're doing board fabrication and assembly, buying one board costs literally the same as buying buying 6 boards. And then the price per board from there will go down and you could be paying— if you're buying— if Apple's buying boards for their phones, they're paying, I don't know, like $1 for each board. But if you were to steal Apple's design and then get a board fabbed, get that board fabbed, it would cost you probably $5,000 to get the board fabbed.
