Slashdot Mirror
New Air Force Satellites Launched To Improve GPS (techcrunch.com)
AmiMoJo writes: This morning, the United Launch Alliance (ULA) successfully launched a Boeing-built satellite into orbit as part of the U.S. Air Force's Global Positioning System (GPS). This $131 million satellite was the final addition to the Air Force's most recent 12-satellite GPS series, known as the Block IIF satellites. The GPS Block IIF satellites were launched to improve the accuracy of GPS. Before the Block IIF series, the accuracy of GPS could be off by 1 meter. With the new Block IIF satellites in place that error is down to 42 centimeters.
42cm until they scramble it in times of war
RTK GPS is accurate to within 1-2 cm lat/long and typically 2-3 cm alt. For now that is about the best accuracy a civilian can get.
phones already use cell towers and wifi networks which are a lot more accurate and faster than GPS
I am not sure about this, but I had thought that phones use cell towers and wifi to get general idea where they are at and then use GPS for more accuracy. Without the inital gross location, GPS takes a lot more time to sync up.
No they aren't. They use a lot less battery power, but they provide far less accurate results. But if you want to keep the location on for an extended period, you need to use network or you'll kill your battery.
Want proof? Look at your maps app- it still uses GPS. And it eats through battery- you can feel your phone heat up when using it, and you can see the battery drop like a rock when navigation is on.
I still have more fans than freaks. WTF is wrong with you people?
You do understand that GPS has non-military and even military purposes that don't involve dropping bombs right?
http://www.nationalgeographic.com/foodfeatures/feeding-9-billion/
GPS can help agriculture be more efficient, thus providing more output per acre, and thus more food for those very children you are so concerned about feeding.
And if you are so concerned about feeding children, may I suggest getting off your fat ass, and going to Africa to see how massively complicated the problem actually is, instead of being the arm-chair quarterback.
You don't need new gear to benefit from these IIF block birds.
The follow on ones, up next will also be backward compatible...though they will transmit an additional civ signal along with transmitting the old backward compatible one as well, to get the new (second) channel you'll likely need new gear, it's years away.
all that "post-processing" could probably be done on the fly if you really needed to, provided things like base stations still existed,
WAAS and DGPS ground stations are all over the place, and you can access the DGPS correction data using a wireless modem. It is used for maritime and aviation navigation at a minimum.
The concern that created SA was not for long-term stationary measurements, but on-the-move guidance for troops and weapons systems which would not have nearby fixed station correction data.