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Comment by ikiris | Hacker News Reader

Its an existential threat to some incumbent last mile providers.

I think it's less an existential threat than forcing them into specific geographic areas where they can still compete favorably. I doubt your Starlink speeds will be anything special in a heavily populated area where people are sharing the spectrum, and that heavy population means that fiber is feasible. Fiber means Starlink is competing against Gigabit plus speeds, delivered individually and not shared (to the degree that the ISP provides enough capacity where they aggregate the connections).

Rural areas and coverage across most/all the United States, even in areas where only satellite phones worked previously, are major draws IMO though.

Agree with this, there’s plenty of areas (Eg non central belt of Scotland from my own experience) outside of cities, where the current provider is the only choice even though the service is slow and unreliable. Starlink could really appeal and gain a solid user base, very quickly.

Starlink is not going to be for end users most likely. The terminal, by all accounts so far, will be far more expensive than a geo terminal due to the motor and the phased array. I guess if you're willing to pay for it, it will certainly solve that problem, but there aren't enough of those customers to be profitable.

There's no need for a motor; that's what the phased array antennas are for.

802.11ac packages already implement MIMO-based beamforming, and I think there are already speciality 802.11ac packages using phased array for backhaul radio links. Phased array beamforming is a matter of size and processing power, but nothing different from cutting edge WiFi and 5G products, and not much different from what's already deployed in many laptops and cellphones. The entire software and hardware stack, including at the consumer level, is already capable of real-time, electronic beamforming. The technology for the Starlink terminals is well established and it could be done cheaply, it's just a matter of whether Starlink has the manufacturing pipeline primed.

Just like with rockets and electric cars, all the pieces exist and are relatively mature. It's just a matter of assembling them cost effectively, and that happens to be Elon Musk's special gift.

I know that, but there IS a motor. Elon has said this himself. what you are describing is far more expensive than a phased array with the scan needed for no motor. It is not a solved, inexpensive problem. 5G and wifi use significantly lower frequencies, which is much easier and cheaper to implement the phased array. Starlink is Ku and Ka band. There are no examples of a consumer version of these that is cheap enough. The only thing that came close is the oneweb, but that's only Ku, and it only exists in a Wyler tweet.

Satellite will never beat local radio (ex: 5G, WiFi) and local radio will never beat fiber, for physical reasons.

The reason comes from the Shannon theorem: C=B*log2(1+S/N). C is capacity (what we want), B is bandwidth, S/N is the signal/noise ratio.

With modern technologies, we are very close to that limit. Both 5G and satellites are using among the highest radio frequencies the atmosphere can carry, the signal power is limited by electrical power requirements and emission power regulations and there is not much we can do about ambient noise. Fiber uses light which, in theory, can carry many orders of magnitude more information but the problematic is different.

But the thing is that this capacity is per channel, and the narrower the channel, the more we can pack in a given area, and that's where satellites are at a huge disadvantage. Satellites, even Starlink satellites, are really expensive, and they are 100s of km away at best. It means they can only project wide beams, even with they fancy beam forming antennas. Ground based antennas can cover a much smaller area and are much cheaper, as a result they have more channels and therefore more bandwidth. Satellites may prove effective in sparsely populated areas, but not in dense cities.

Fiber, and even copper wires are the extreme case. The channel is a single wire, you can pack hundreds in a cable you can hold in your hand. Compared to wireless transmission, bandwidth is essentially unlimited.

Fiber actually has limitations based on the length of the cable. Photons that travel perfectly straight arrive faster than photons that enter the cable at a steep angle and bounce off the walls a lot. Because of this, as you increase transmission rate, you start to get interference between signals, and instead of a clear On-Off, you start to get various degrees of brightness until the signal becomes too degraded.

Radio, whether local or via LEO satellites, absolutely can beat fiber. Routinely. That is much of the value proposition of SpaceX's product.

Microwave links from Chicago to New York claimed hundreds of millions in investment exactly on the prospect of selling reduced transit time at a premium. Similar gains on the New York - London channel, via Starlink, would be much more valuable.

The reason fiber is slow is that the signal does not propagate in a vacuum. It loses 30+% of the speed of signals propagated through air or vacuum.

Where fiber wins is on bulk bandwidth. A radio link has limited capacity, but it can get the first few packets through soonest. Starlink might start out with some pretty draconian tradffic caps.

I have heard of hollow-core fiber, where the beam travels in what amounts to a tube in the middle of the fiber, but I don't know of any deployed.

Fixed wireless is that too.

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