I was wondering if you could please confirm the definition of the column title 'DDER_m' within the RDD (raw double difference) output from DDBase.exe?

Is this is estimated "true" range?

Where therefore for L1 (and L2), the following could be said for "measured" and "true" ranges:

resL1_m = DDL1_m - DDER_m

If not, is there any other way to calculate ranges using GPSTk? (apart from lengthy Excel stages and formulae)

Many thanks,


-- MichaelRigby - 12 Sep 2007


ALERT! If you answer a question - or have a question you asked answered by someone - please remember to edit the page and set the status to answered. The status is in a drop-down list below the edit box.

Hello Michael, The program wheresat can calculate and output a range, if the antenna position is input.

If you are a Windows user -- Wheresat was omitted from the last Windows build but it will be part of the next build and is part of the 1.2 Windows binary build. We have an inhouse version we built we can send you if you want it.

Regards, Ben

-- BenHarris - 12 Sep 2007


Thanks for your quick reply Ben! That's great thank you very much.

At this stage I'm hoping to incorporating DDBase output into another program and I would love to use the DDER_m value if possible, do you know if this the range?

(I suppose I can check this query using Wheresat. I just need confirmation for justification smile )

Thank you again,


-- MichaelRigby - 12 Sep 2007

Thank you so very much smile

-- MichaelRigby - 12 Sep 2007

Michael, Yes DDER_m is the 'true' range based on the ephemeris with corrections applied, in meters. Brian

-- BrianTolman - 12 Sep 2007

No such template def TMPL:DEF{PROMPT:supportquery}
Topic revision: r6 - 27 Nov 2007, RickMach

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