[teqc] Obtaining only position information from RINEX data using teqc qc-full

[Lou Estey]

Dr. Pierre Cilliers (Hermanus Magnetic Observatory, Hermanus, South Africa)
asked me to post this to the teqc list.

cheers,
--lou

-------- Original Message --------
Subject: Re: Obtaining only position information from RINEX data using teqc qc-full
Date: Wed, 05 Mar 2008 07:21:33 -0700
From: Lou Estey <lou at unavco.org>
To: Pierre Cilliers <pjcilliers at hmo.ac.za>
CC: Lou Estey <lou at unavco.org>
References: <268574D05043B442BD5113C32AC4FEFF050A7F at her-dc01.her.hmo.ac.za>

Pierre,

> I would like to estimate the position of a mobile GPS dual frequency 
> receiver.
>  
> Is it possible to obtain only the receiver position estimate from RINEX 
> Observation and Navigation data using teqc in qc-full mode, that is 
> without all the other information normally provided in the systems 
> output file?
>  
> What are the minimum number of observables and epochs to obtain a 
> position estimate with teqc?

You could run the qc with the extra +eepx or +eepg options.  These
do an epoch-by-epoch position based on the available pseudoranges.
(Values are returned either in WGS-84 xyz cartesian coordinates or
geographic coordinates.)  Minimum observables are pseudoranges from
5 SVs, plus the navigation messages for those SVs.

However, any position from teqc, including these, should only be
treated as very approximate, and good only to +/-100 meters or so.

--lou

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Louis H. Estey, Ph.D.              office:  [+001] 303-381-7456
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"If the universe is the answer, what is the question?"
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