China's GPS 'rival' Beidou • Hacker News Board

Re: China's GPS 'rival' Beidou

#41

Post by eiaoa » Mon, Oct 22, 2018, 9:02 PM UTC

snops wrote: post #23

Retric wrote: post #17

Earlier quoted context omitted.

COCOM is a non issue when building your own devices from scratch. GPS satellites are transmit only so they can’t impose such limits directly it’s device manufacturers that implement COCOM.

You are right that COCOM is not the issue, but there are other measures. The new military M code transmitted from the latest satellites is encrypted with a frequently changing key, so in the event of a war the DOD can disable the civilian signal as the M code will work standalone, hence a third party nation cannot rely on GPS. The previous P(Y) code was also encrypted, but is theorised to need the civilian C/A code a…

> so in the event of a war the DOD can disable the civilian signal as the M code will work standalone, hence a third party nation cannot rely on GPS.

They also had the option in older satellites of turning on selective availability, which would degrade the civilian location service from 5-meter to 100-meter accuracy without affecting the military service. Purportedly newer GPS satellites don't have the option anymore.

https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_...

Re: China's GPS 'rival' Beidou

#42

Post by liftbigweights » Mon, Oct 22, 2018, 9:03 PM UTC

majia wrote: post #21

"We are likely to see an increased bifurcation of the world into two camps - 'pro-China' and 'pro-US'", says Blaine Curcio, founder of Orbital Gateway Consulting Why do some people view it as a with-us-or-against-us problem? Combining beidou with GPS gives a better accuracy. Some competition and collaboration in the GPS field can benefit us as a whole.

> "We are likely to see an increased bifurcation of the world into two camps - 'pro-China' and 'pro-US'", says Blaine Curcio, founder of Orbital Gateway Consulting

Why just two? If our stranglehold on the world breaks, the EU and Russia are easily capable of carving out their sphere of influence.

People really underestimate how populous and wealthy and powerful the EU is.

It's strange how the narrative changes in such a short time period. Just 10 years ago, I remember people talking of "chimerica" as if the US and china were going to merge into a single world ruling entity.

Re: China's GPS 'rival' Beidou

#43

Post by JumpCrisscross » Mon, Oct 22, 2018, 9:03 PM UTC

slededit wrote: post #34

JumpCrisscross wrote: post #28

Earlier quoted context omitted.

> Any country that can launch a satellite has a technology to destroy one It's easier to put something in orbit than to knock something out of orbit.

You can destroy something without taking it out of orbit. The pieces will happily carry on along their orbital trajectories.

It's easier to put something in orbit than to hit something in orbit.

Re: China's GPS 'rival' Beidou

#44

Post by nutjob2 » Mon, Oct 22, 2018, 9:04 PM UTC

sbradford26 wrote: post #2

GPS has become so ubiquitous I honestly forgot that it was something that could be owned. It is cool to see some competition in the GPS world.

GPS systems are not so much 'owned' as 'paid for'.

Re: China's GPS 'rival' Beidou

#45

Post by walrus01 » Mon, Oct 22, 2018, 9:10 PM UTC

kejaed wrote: post #24

Note you can buy off-the-shelf GPS modules today that will work across all four GNSS: https://www.u-blox.com/en/product/neo-m8-series

One of the reasons for this, about seven years ago Russia put a 30%+ import tariff on any mobile phone that didn't work with GLONASS. Thereby motivating chipset makers like Qualcomm to integrate GLONASS receive features into their existing RF chipsets.

Re: China's GPS 'rival' Beidou

#46

Post by comboy » Mon, Oct 22, 2018, 9:14 PM UTC

nutjob2 wrote: post #40

comboy wrote: post #35

Why is 'rival' quoted?

Because GPS do not rival each other in any practical sense, instead they complement each other. More GPS systems means more satellites means greater accuracy for users. Let's hope even more countries get into GPS "rivalry."

Oh, I guess you're right. In my mind it was like "not really a competition" in a negative aspect but it turns out the negativity was in my mind.

Re: China's GPS 'rival' Beidou

#47

Post by romwell » Mon, Oct 22, 2018, 9:22 PM UTC

kec wrote: post #13

justfor1comment wrote: post #6

India did something similar a few months ago. Each country wants to build it's own GPS for military purposes. At some point we have to stop calling it 'Global' Positioning System.

The "global" refers to the fact that it works globally, not that it exists for the good of humanity. Navstar (owned by USDoD, what is commonly called "GPS"), GLONASS and soon Galileo all have global coverage.

Yup, GLONASS = GLObal NAvigational Satellite System.

Although one should note that name is the intention; it has not always had global coverage (it does now), and may not always have global coverage in the future (say, if they decide to increase the precision in a strategic area at the cost of loss of coverage in others).

Re: China's GPS 'rival' Beidou

#48

Post by fatjokes » Mon, Oct 22, 2018, 9:33 PM UTC

liftbigweights wrote: post #42

majia wrote: post #21

"We are likely to see an increased bifurcation of the world into two camps - 'pro-China' and 'pro-US'", says Blaine Curcio, founder of Orbital Gateway Consulting Why do some people view it as a with-us-or-against-us problem? Combining beidou with GPS gives a better accuracy. Some competition and collaboration in the GPS field can benefit us as a whole.

> "We are likely to see an increased bifurcation of the world into two camps - 'pro-China' and 'pro-US'", says Blaine Curcio, founder of Orbital Gateway Consulting Why just two? If our stranglehold on the world breaks, the EU and Russia are easily capable of carving out their sphere of influence. People really underestimate how populous and wealthy and powerful the EU is. It's strange how the narrative changes in suc…

No one doubts the EU's power, but they doubt its stability and unity. With the surge of right wing nationalist governments in Europe it's a fair concern.

Re: China's GPS 'rival' Beidou

#49

Post by slededit » Mon, Oct 22, 2018, 11:46 PM UTC

JumpCrisscross wrote: post #43

slededit wrote: post #34

Earlier quoted context omitted.

You can destroy something without taking it out of orbit. The pieces will happily carry on along their orbital trajectories.

It's easier to put something in orbit than to hit something in orbit.

Well I'll disagree with my own unsubstantiated claim. Consider that its easier to manufacture flak shells than make airplanes. The same applies to space.

Re: China's GPS 'rival' Beidou

#50

Post by baybal2 » Tue, Oct 23, 2018, 1:33 AM UTC

Analemma_ wrote: post #3

It’s interesting and odd to me that Beidou requires two-way communication, as opposed to other satellite tracking systems where the receivers are purely passive and satellites only transmit, not receive. Is there an explanation for why this was done?

Yes, first generation beidou were mandatory two way, to do crypto handshake. The Party wanted "more control," just as usual.

The idea was realisedly lunatical even back then, but party boffins really though that reality and laws of physics will yield to party's mandate.