On 5/18/15 7:59 PM, Chris Albertson wrote:
Yes GPS can do better than 50M but we are talking about a single fix
from a cell phone in a moving car not a survey receiver. . The
displayed location is better because the phone applies a filter to the
location data. Some thing like a Kalman filter. I doubt the iPhone
can get within 10M from a moving car.
As for Iridium being an expensive for pay service. But that is
because most users SEND data. This new service is broadcast and costs
do not depend on the number of users. Apple has sold 130,000,000
phones already just in this half of 2015. A one time payment of about
$1 per phone might cover the costs.
Why iridium? Why not Sirius or XM or DBS. Unless you want something
world wide, as opposed to "populated areas served by broadcast radio and
TV"
Heck, you could probably buy transponder time on a C-band satellite and
radiate a GPS assist signal (that's what WAAS is, after all)
hmmmmm……I do believe the marketing boys have been playing with the
numbers. You would have to start
from a >50 M error to get them to make much sense based on what they are
doing.
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