Comment by shaklee3 | Hacker News Reader

Comment by shaklee3 | Hacker News Reader

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This article seems to be trying to get to a conclusion without a lot of support.

>This works out to be around $100k per satellite, more than 1000 times cheaper than a conventional comsat launch

A standard comsat satellite can potentially cover 1/3 of the globe with hundreds of Gbps of bandwidth. Starlink covers a tiny area with much lower bandwidth. Strength in numbers.

> 100MB per second using advanced coding such as 4096QAM

QAM isn't used in satcom, and certainly nowhere near 4096. Why the assumption?

> Each Starlink satellite includes all the complicated electronic switching gear found linking optical fibers together

Nope. The first batch likely had a problem and won't have inter-satellite links (per the hint from shotwell)

> All up, 2500 channels each supporting 58 Gbps is a staggering quantity of data, roughly 145 Tbps

The MIT study showed simulations that was about 20x less than that, so I'm not sure where these numbers are coming from without doing a proper simulation.

The piece that was left out, and possibly the most important, is user terminal cost. It will certainly be more expensive than a GEO antenna, and you need to recover that cost from the user. So far, there have been no practical, cheap, high-performing phased array that I know of.

The first batch didn’t have inter-satellite comms onboard due to the mirrors being too robust and presenting a risk of surviving reentry.

> will certainly be more expensive than a GEO antenna

I don't think this is necessarily true. Iridium antenna and RF circuitry is much cheaper than GEO because it doesn't have to receive a weak signal from far away.

That's not really what drives cost in this case. That's a very small part of it, but the phased array aspect alone is expensive based on frequency, which they're using the same ones as GEO.

The antenna cost has been confirmed to be targeting a price of 300$ per unit.

Right, so targeting is one thing, and $300 will certainly be a good price point. But we'll have to see if they hit it. Many, many others have tried and failed.

What are physical limitations? With phased aperture array we have 1) individual antennas 2) individual electronics for each antenna. Which of them is expensive?

To the best of my knowledge, they can make cheap phased array antennas that have poor performance. Poor performance can cut substantially into the overall satellite capacity, so the only way to make up for that is to charge more money. Then your service is less attractive, and people won't sign up. So you really need really well performing, and inexpensive.

>The antenna cost has been confirmed to be targeting a price of 300$ per unit.

Like the Model 3 was "targeting" $35,000 before incentives.

> So far, there have been no practical, cheap, high-performing phased array that I know of.

Do you thing that is more due to technical limitations or more due to relatively small markets for such antenna that perhaps has not led to economies of scale?

I think technology limitations. Directtv/dish would have used it already if it was cheap enough since it's easier to install.

They would only have done it if an off-the-shelf solution was already available.

StarLink is going global and the target price for their terminals is $USD200 or so.

That's pure speculation. There's nothing special about starlink for buying power. Anyone would have done it if a cheap solution/off the shelf was available.

The point is not about buying power, it’s about potential income versus up front development cost.

That's the exact same thing every company in every business has to solve. What makes starlink unique in this case?

The up front development cost is slightly lower than a few years ago, and the potential income is astronomical.

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