[Talk-de] HighPrecision GPS receiver home build?

[Frank Sautter]

marcus.wolschon at googlemail.com schrieb:
> On Wed, 18 Nov 2009 12:14:20 +0100, Frank Sautter
>> und wikipedia zu RTK
>> http://en.wikipedia.org/wiki/Real_Time_Kinematic
> 
> Das Projekt und die Webseite gingen auch schon auf der Mailing-Liste
> des Paparazzi Autopiloten rum.
> Das Teil braucht einen zweiten Empfänger an einer EXAKT bekannten Positon
> in der Nähe.
ich darf mal den wikipedia artikel zitieren:
The difficulty in making an RTK system is properly aligning the signals. 
The navigation signals are deliberately encoded in order to allow them 
to be aligned easily, whereas every cycle of the carrier is similar to 
every other. This makes it extremely difficult to know if you have 
properly aligned the signals or if they are "off by one" and are thus 
introducing an error of 20 cm, or a larger multiple of 20 cm. This 
integer ambiguity problem can be addressed to some degree with 
sophisticated statistical methods that compare the measurements from the 
C/A signals and by comparing the resulting ranges between multiple 
satellites. However, none of these methods can reduce this error to zero.

 > Bringt uns also nicht.
doch, auch ohne referenzempfänger wird die genauigkeit deutlich höher 
(~40cm radius), aber die "integer ambiguity" kann nur mit 
referenzempfänger eliminiert werden (~1cm radius).

grüße
  frank