> When you start getting to less than a meter.. For absolute, you need to > start worrying about stuff like solid earth tides, plate movement, a whole > host of things are all contributors in that 10-100 cm range.
Absolute and relative... can be a word game. It depends what DATUM (coordinate system) you want to have your answer in. > For precision attitude, e.g gun laying, differential carrier phase works > pretty well, but consider what sort of phase measurement performance is > needed over a say one meter baseline with 20cm wavelength. The below datasheet mentions 0.22deg/m baseline. You need decent antennas and limited multipath to get there. http://javad.com/downloads/javadgnss/sheets/DeltaD_Datasheet.pdf There are also some quotes on relative positioning performance. > On Dec 5, 2010, at 11:31 AM, Brooke Clarke <[email protected]> wrote: > >> Hi Brian: >> >> A friend has an Android cell phone with built in GPS. It has a >> resolution of 0.0001 arc seconds as does the GPS I just got for my >> camera: The lat/lon resolution is fairly unimportant as long as it resolves enough. Neither the antenna nor the receivers used in cell phones are good for better than a few meters in positioning accuracy. -- Björn _______________________________________________ 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.
