China's version of GPS now has more satellites than US original

Gustomaximus wrote: post #3

aritmo wrote: post #2

Is there any information about the accuracy of Beidu compared to Galileo?

In the article the say accuracy is coming down to 1m vs 3-5 for other GPS

> In the article the say accuracy is coming down to 1m vs 3-5 for other GPS

In which areas?

Re: China's version of GPS now has more satellites than US original

#5

Post by flywithdolp » Tue, Aug 20, 2019, 9:24 AM UTC

The space race

Seems like that's the next goal of the big nations.

How can they have more control over the space

Re: China's version of GPS now has more satellites than US original

#6

Post by stunt » Tue, Aug 20, 2019, 9:26 AM UTC

wolfgke wrote: post #4

Gustomaximus wrote: post #3

Earlier quoted context omitted.

In the article the say accuracy is coming down to 1m vs 3-5 for other GPS

> In the article the say accuracy is coming down to 1m vs 3-5 for other GPS In which areas?

> As of June 28, Chinese satellites were observed more frequently than GPS satellites in 130 of 195 countries (U.N. member states plus the Vatican and Palestine). More than 20 BeiDou satellites were observed over mainland China.

Re: China's version of GPS now has more satellites than US original

#7

Post by lolc » Tue, Aug 20, 2019, 9:33 AM UTC

> When using BeiDou for car navigation, the receiver could theoretically transmit the car's location to a satellite in orbit, said Dean Cheng, a senior research fellow at the Heritage Foundation in Washington.

Details on this? What does "theoretically" mean? Are there known protocols for this? Implementations? A lot of things could "theoretically" be done but aren't in practice.

Re: China's version of GPS now has more satellites than US original

#8

Post by nullc » Tue, Aug 20, 2019, 9:38 AM UTC

It doesn't help that the GPS modernization project was delayed by a decade re-prioritization after 9/11.

Though this result is also because BeiDou has intentionally uneven coverage via satellites with inclined orbits that result in much better coverage (and better signal angles, high off the horizon) in asia.

Re: China's version of GPS now has more satellites than US original

#9

Post by willis936 » Tue, Aug 20, 2019, 9:42 AM UTC

Gustomaximus wrote: post #3

aritmo wrote: post #2

Is there any information about the accuracy of Beidu compared to Galileo?

In the article the say accuracy is coming down to 1m vs 3-5 for other GPS

With military receivers (or codeless phase tracking) the current constellation is good down to centimeters.

Re: China's version of GPS now has more satellites than US original

#10

Post by willis936 » Tue, Aug 20, 2019, 9:43 AM UTC

lolc wrote: post #7

> When using BeiDou for car navigation, the receiver could theoretically transmit the car's location to a satellite in orbit, said Dean Cheng, a senior research fellow at the Heritage Foundation in Washington. Details on this? What does "theoretically" mean? Are there known protocols for this? Implementations? A lot of things could "theoretically" be done but aren't in practice.

This seems rather counter to what I know about GPS. It is a one way link.