China To Complete Beidou Competitor To GPS With New Launches (apnews.com) 23
China said Friday its Beidou Navigation Satellite System that emulates the U.S. Global Positioning System will be competed with the launch of its final two satellites in the first half of next year. From a report: Project director Ran Chengqi told reporters that the core of the positioning system was completed this month with the launch additional satellites bringing its total constellation to 24. That was up from 19 the year before, making it one of rising space power China's most complex projects. Ran described the system at a rare news conference as having "high performance indicators, new technology systems, high localization, mass production networking and a wide range of users." "Before June 2020, we plan to launch two more satellites into geostationary orbit and the Beidou-3 system will be fully completed," Ran said.
Confused (Score:1)
Re:Confused (Score:5, Informative)
Satellite navigation doesn't require the satellites to be in any particular orbit. Beidou is similar but not identical to GPS and includes geostationary, inclined geosynchronus, and MEO satellites for improved coverage over Asia.
Re: Confused (Score:1)
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Beidou geostationary satellites were originally launched before Beidou global. The initial geostationary constellation only provided location service over a relatively narrow range of longitudes, and accuracy drops off as you move away from the equator.
The Russian GLONASS doesn't use geostationary satellites. It's kind of quirky in that it requires one more satellite to be in view than GPS (e.g. you need to be able to see two satellites to get the time, three to get any kind of approximate position fix, a
One question (Score:1)
Who controls the off switch? Rhetorical, yes, but, what the hell... After all, do we want "Skynet"? We do need something that requires more than one person to disable it though.
You know it just glorified clocks, right? (Score:2)
What exactly are you talking about? Are you a bot?
Those satelites are just sending a time signal. Which, together with their positions and triangulation can be used to find one's position.
Re: (Score:1)
The master clock is on the ground. The signal can be degraded just like GPS. It's not a good idea to leave any single individual or government in charge if/when people become dependent on the service.
Re: You know it just glorified clocks, right? (Score:2)
If you become dependent on the govt, that is by design.
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The government is us. Whatever it does, we are responsible.
Re: You know it just glorified clocks, right? (Score:2)
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You mean, exactly like GPS, Glasnost and galileo?
It's UPS, Glasnost, and Galleon. Jeeze, some people can't even manage a cut&paste.
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I’m not understanding the concern you’re trying to express, unless you’re worried about getting stranded mid-trip should the constellation get disabled - but then the “Skynet” reference doesn’t make sense.
Assuming this functions like GPS, then its use is completely passive. The satellites and their network have no knowledge of who’s using them.
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Sadly, useless for improving GPS accuracy. (Score:1)
As positions are deliberately scrambled inside a 500m radius, for "reasons". At least for civilians.
Re:Sadly, useless for improving GPS accuracy. (Score:4, Informative)
Where did you read this? Everything I've read says accuracy is similar to GPS. https://gssc.esa.int/navipedia... [esa.int]
GPS is as accurate as it is (5m typically) because the US broadcasts ground-based WAAS obvservations through the GPS satellite network which your phone picks up and uses to "correct" with. Of course that only helps in North America. I think there are similar systems in operation to make GPS more accurate (and probably Galileo too) in Europe.
Also RTK solutions are possible with Beidou also. Certainly they can contribute to a multi-constellation RTK solution: https://www.septentrio.com/en/... [septentrio.com]
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EGNOS. Japan also has one.
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The Japanese satellite-based augmentation is called QZSS (Quasi-Zenith Satellite System). It's usable in Indonesia and Australia as well. There actually seem to be [wikipedia.org] in operation now.
The more the merrier; we can use all at same time (Score:5, Interesting)
With modern GPS chipsets, receivers can work with several constellations all at once. No one entity can shut things down and deliberate poisoning of position signals might be detectable. My phone works with GPS, Glonas, and Galileo (all at once)
Currently I'm working with some ZED-F9P receivers, which are multi band and RTK capable out of the box. They fix with GPS, Glonass, Galileo, Beidou, and QSZZ satellites, and can do RTK calculations with all of these. Pretty useful and amazing device. Typically it sees around 20 or more satellites at any one time in the sky. With good observation data about all these different satellites, it can resolve an RTK solution in seconds. Not bad for $200.
Censors (Score:2)
Some locations are censored though. Instead of telling you where you are, users get a message that reads, âoeStay right where you are, technical support will arrive in a moment.â