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This all just makes it clear that a military version of Starlink is needed, and that's what the DoD and others are building.

I also think UWB radio is going to be big in the future for communicating with nearby devices in warzones.

And lasers, both in space and in free space.

What makes UWB better positioned than other modulation/transmission technologies?

most receivers see it as white noise, if they don't know the timing

Is that fundamentally different from e.g. CDMA using cryptographic spreading sequences, though?

In the end, any sufficiently efficient signal is indistinguishable from noise to anybody but the intended receiver(s), no?

Yes fundamentally different[1]. There are dozens of implementations under the Ultra Wide Band definition.

[1] https://en.wikipedia.org/wiki/Ultra-wideband

Can you say how, specifically with regards to "receivers seeing it as white noise without knowing the timing"?

As I understand it, the same is true for e.g. DSSS (for receivers not knowing the spreading code), and the primary advantage of UWB is its precise ranging capability (due to its ability to reject multipath propagation errors and the generally high bandwidth, yielding better spatial resolution).

UWB radio transmits below the noise floor, you're going to have a hard time finding any signal there or even know if a signal is being transmitted. You can go crazy misidentifying noise combinations as signals. In that sense you need to know almost everything about it to intercept it.

That's the same for (wide) spectrum spreading though, right? Some of these signals are also below the noise floor before correlation, and you need to know the spreading code to detect them.

I studied ultra wideband decades before they started to write papers refering to UWB standard definitions [1] so I might be out of tune (pun intended) with current definitions.

A transceiver could use attosecond 10^−18, femtosecond 10^−15 picosecond 10^−12 or nanosecond 10^−9 pulses at very irregularly intervals. That seems (almost) random to any observer but not to a receiver which has pre-agreed those irregularly intervals with the transmitter (for example with quantum key distribution, with entangled particles). The receiver measures if there was a signal or not. It does not use power level, frequency, or phase (or a combination of these) of a sinusoidal wave but by generating radio energy at specific time intervals and occupying a large bandwidth, thus enabling pulse-position or time modulation.

Not just spacial distribution can be used. You could use polarised photons, electron spin, etc.

In my wafer scale integration [2] I use very few free space photos to flip a 1 v transistor in an ultra wideband mode.

I refer you to [3] for [4] for a better explanation, even though ultra wideband is not mentioned specifically.

Contact me directly, I'll be happy to lecture for a few hours to answer your question.

[1] https://scholar.google.com/scholar?hl=en&as_sdt=0,5&q=ultra+...

[2] Smalltalk and Self Hardware https://vimeo.com/731037615

[3] Stanford Seminar - Saving energy and increasing density in information processing using photonics https://www.youtube.com/watch?v=7hWWyuesmhs&t=272s

[4] Attojoule Optoelectronics for Low-Energy Information Processing and Communications: a Tutorial Review https://arxiv.org/abs/1609.05510

The same is true for DSSS only within a relatively narrow frequency band, originally of at most a few tens of MHz, now up to a few hundred MHz.

For UWB, the energy of the signal is spread over a much wider frequency band, of at least a few GHz and up to tens of GHz. Therefore UWB behaves like a white noise with a much greater bandwidth than DSSS.

It is not difficult to jam the entire band that can be used by certain kinds of DSSS signals or to receive all of it and process it digitally to search for signals within it.

Such operations are much more difficult for the much greater bandwidth used by an UWB signal.

Ah, that makes sense, thank you! So if I understand it right, they'd be the same/very similar if we could do direct-sequence spreading over multiple GHz, but we can't, so we do UWB instead? Is the modulation just practically easier to achieve in hardware?

And regarding jamming resistance: Couldn't a jammer just transmit random pulses in the frequency band in question? Why is jamming harder than just transmitting a lot of useless data on the same channel using whatever modulation the targeted transmitter uses as well? Or is there just too much space (or rather, time) to cover with reasonable transmit power?

> You can now disable the Starlink Wifi router but only if you patch the encrypted firmware and spoof the account credentials.

Isn't it possible out of the box these days in "bypass mode"?

https://www.starlinkhardware.com/how-to-bypass-the-starlink-...

Depends on the version and revision and what you need to achieve, its is not only Wifi disabling.

regular version, recent revision. disabling wifi is a checkbox on the phone app not """extensive conversion is only for very capable hackers and has been done by only three people on our planet"""

English is not my native language, you might have taken me too literally. You have to be a very capable hacker to modify all the different Starlink firmware of all the chips involved. There are dozens of reasons to do that, unrelated from disabling WiFi.

And no, a GUI check box has little relation to what the hardware actually does.

> There are dozens of reasons to do that, unrelated from disabling WiFi.

You're moving goal posts now. If the stock firmware/software now allows disabling Wi-Fi, you don't need to hack the hardware.

And if you can't trust the stock firmware, i.e. you have reason to assume that it's actively malicious (e.g. by turning the Wi-Fi back on randomly), how can you trust the hardware? Who's to say that it doesn't, e.g., have an undocumented transponder feature that replies to a specific type of interrogation?

You measure and reverse engineer. That is what hackers should do.

>You're moving goal posts now.

I'd say you where interpreting my comments on hacking too narrowly.

I’m surprised that opening the router and physically disabling the wifi antenna is not a solution. I would understand that running the router in a faraday cage is not viable as the ethernet cable has to get from the router to the dish.

A faraday cage with a hole only big enough for an ethernet cable would almost certainly still block enough wifi that the signal would only be detectable for a few meters. Probably not very much would leak through the cable.

It would be dwarfed by the emanations from the, you know, space transmitter co-located with it. Locating the dish isn’t the issue, the proposal was using fiber to make the dish (detectable) and the operator (vulnerable) separated by distance.

They seemed to say that a special software hack was required to block the wifi, so i was wondering why the obvious physical hacks were not worth it.

There is more to it.

For example, do you trust SpaceX to not relay your location to your enemy? Do you want to broadcast your identity at all if there can be a man-in-the-middle-attack? A dozen other reasons....

If you don't, should you be using a highly directional (Starlink achieves the capacity it does through spatial reuse allowed by directional antennas on both ends, so the satellites do need to know where you are pretty precisely), proprietary-hardware-requiring, inherently authenticated (for billing purposes), and generally very civilian focused satellite service?

A military service would probably use wider beams coming from the satellite, as well as different encryption (making it impossible to distinguish which terminal is being transmitted to on which beam and not using correlatable identifiers on unencrypted protocol layers at all).

Using civilian communications technology like cell phones has been a bad idea, as evidenced in the same conflict.

If you don't trust the software or the server, you can reflash the firmware and deploy the hardware in your own way, similar like we do with OpenWRT.

Use Starlink dishes as phased array point to point links across 500 km without the v2 Satellites?

There are 200 Ukrainian drone startups alone, many more in other countries. They all hack firmware. Hacker News readers should not be surprised.

The problem isn't the firmware, it's the protocol.

If the protocol requires you to reveal your precise location to the network (so that satellite beams can correctly target you), how would you get around that using your own open firmware/hardware?

The same goes for authentication using (potentially) long-term stable or even public identifiers, as is the case for e.g. the IMSI with GSM (not sure if later 3GPP generations finally fixed that): A GSM network won't let you attach without revealing your IMSI over the radio interface at least once. You can spoof it, but then you won't get any service.

> Use Starlink dishes as phased array point to point links across 500 km without the v2 Satellites?

That's a completely different scenario than the one we're talking about here ("why can't military users relatively easily put some distance between the Starlink terminal and its users in a warzone?"), and one which I'd assume the military to have existing solutions for.

I was indeed referring to different scenario's at the same time

Indeed, the ethernet cable and connectors are antennes too.

The entire terminal is one big antenna, by definition!

Are Starlink terminals really directional enough for EMI from an Ethernet port to be a bigger omnidirectional concern than the many watts of power they transmit skywards as part of their normal operation?

Hundreds ro thousands of antennes, actually.

Different wavelengths, infrared its already a target in a warzone.

>10Ghz is another type receiver.

If I am following you correctly, disabling the wifi router is to avoid detection right? If so why not encase it an an RF pouch or RF shielding netting to block the signal?

Yes, why not? Its not so simple You have to science the shit out of this - Mark Watney (The Martian)

Doesn't the device need satellite connectivity?

Seems easy enough to work round. Just run a fibre optic cable to the operator

Not entirely easy. SFPs and FPGA's need to be in the mix, software patches, power supplies, etc.

Why? Worst case, couldn't you put the Starlink terminal, router, power supply and all in position A, together with a (worst case) Wi-Fi to fiberoptic Ethernet bridge running to position B?

The Starlink terminal is already a giant transmitter, after all.

You can loop the fiber to a far of location of the rest, no need to be point to point.

Use a Yaosheng injector