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Comment by emiliobumachar | Hacker News Reader

Export control has huge downsides and I agree with the general sentiment that the US overdoes it. However, logistics and navigation have obvious military applications. A state-of-the-art GPS receiver can slot straight into a missile.

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So? A state-of-the-art CPU can also slot straight into a missile. As can nuts and bolts, batteries, radios, and all sorts of other equipment.

Speaking of state of the art CPUs, I own a couple years old "KiwiSDR" web-ui receiver which devotes some CPU cycles to implementing a GPS rx and it uses the GPS lock to discipline the internal oscillators such that the radio is driftless and perfect frequency accuracy. It works pretty well. My receiver is somewhat more frequency stable than some local AM broadcasters, which is weird to see in the waterfall display; many local broadcasters do GPS discipline, of course.

Pretty sure the code is at

https://github.com/jks-prv/Beagle_SDR_GPS

Note that the hardware Skyworks SE4150L chip is an RF front-end, all the math is done in software, the chip merely attaches to the GPS antenna and squirts out a very raw digital bit-stream of data, its hardly a full GPS squirting out NMEA RS232 serial data. I am aware of SDR hardware that does the RF work in software, which is a slight step beyond the KiwiSDR.

Technology is not distributed smoothly and software defined GPS is cheap enough that everyone except cheap consumer gear can implement it. Someday, presumably, computing power will be cheap enough that your microwave oven and clothes washer will not bother with expensive hardware to have a semi-accurate timer, they'll just use cheap SDR code in a FPGA to listen to GPS to time your microwave popcorn and clothes spin cycle. That's the fundamental problem with regulations like this, they don't slow down "state actors" they just stand in the way of (taxable, profitable) commercial exploitation.

Post 2000, post 2010 at worst, no serious missile program will ever lack an unlimited GPS, but post regulation, the technology will be crippled from entering consumer goods.

Now what is interesting to speculate is it would be destabilizing if we know that they know how to crack the military P(Y) code or the newer M code for higher resolution positioning. I'm not sure that would help with missiles but if our secret squirrels are freaking out about the generic topic of software GPS, that would imply some state level actor (or lower?) has a crack or exploit for the math behind P(Y) code or M code streams, which has interesting implications for other crypto systems.

I think if they have the rocket scientests to design and manufacture missiles in the first place then export control of GPS chips is security theater - they have advanced mathematics and supercomputers by missle tech standards with just a desktop computer.

Food has military applications as well - because soldiers need to eat.

> A state-of-the-art GPS receiver can slot straight into a missile.

I thought civilian grade GPS didn’t work at high speed or high altitude (meaning missile rather than aircraft) for exactly that reason?

What about the plethora of cheap chinese ones?

Does the USA actually manufacture any of the things on the list any more?

Chinese hardware designs are generally third rate. Everyone just prefers to focus their ire on butterfly keyboards.

> Chinese hardware designs are generally third rate.

Depends on the price bracket, but this is generally an outdated view.

It's worth noting that the EU, Russia and China all either have developed, or are developing, state of the art navigation systems of their own and thus there's no dependence on GPS as there once was and thus the utility of any export controls on it is limited at best.

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