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Comment by mkchoi212 | Hacker News Reader

I thought this was an April fools joke once I clicked on the link. The bandwidth they are operation on (54 MHz) is ridiculous though! Truly sci-fi-ish stuff going on here. Also, did Amazon build this from scratch or did they acquire a company that had the basic infra for this kind of stuff?

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Lockheed is building out the ground infrastructure network [1]

[1] https://spacenews.com/amazon-lockheed-venture-casts-shadow-o...

Not really, that's the bandwidth of an average mid-end SDR like LimeSDR(300$) or BladeRF(500$)

I have never heard of a LimeSDR putting out a 54Mhz wide signal for broadcast. Can you describe how you are configuring things?

Haven't worked with LimeSDR myself, but here's the paper that suggests that it's possible https://upcommons.upc.edu/bitstream/handle/2117/119623/memor...

I was curious bout this as well. Do people get 500 Mhz allocations? Or are there no allocations because things are directional? I think they support a 500Mhz wide downlink?

What's so weird about 54mhz? It's very close to the somewhat commonly used 6 meter band by hams

Bandwidth and frequency are very different. They have a 54MHz wide uplink, at whichever of the supported bands you want.

I'm a person who knows nothing about these things, and my quick googling didn't help me - how "fast" is 54MHz wide uplink? Can it be measured in internet network speeds, or in what kind of way can I compare the speed of it?

It depends on the SNR. You can assume that almost all satellite connections use between 0.2 and 3 bit/s/Hz. It's likely closer to 1 bit/s/Hz though.

So operating with 54MHz of bandwidth would result in a transfer rate of somewhere on the order of 54 Mbps?

Many cable channels are using DVB-S2 8PSK at 5/6 rate. That would be 110 Mbps in 54 MHz (45 Msyms/s).

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