On Tue, 5 May 2015 22:01:29 +0000 Mark Sims <[email protected]> wrote:
> Should be fun when it becomes available... they claim they can get > accurate carrier phase info using a cheap antenna in the phone... > and in real time. It should also be able to get accurate time. > http://www.eurekalert.org/pub_releases/2015-05/uota-ncg050415.php >From what I know about carrier phase measurement, I am not so sure they can actually deliver this accuracy in urban environments. Yes, carrier phase measurement can give you cm level accuracy (after you solve the integer ambiguity), but the biggest contributor to dilution of precision is multipath and refraction (in urban environments). These can easily make up several meters. I have experienced my cell phone to be off by ~300m for several minutes in an environment where I "only" had a large tree and some smallish houses in a residential area. Yes, this was most likely just a fluke of the gps receiver, but still, the biggest problem in the environment, where most people would use gps for this kind of thing, is not the limit of precision due to code-only tracking. But anyways. Let's see what they will deliver. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
