Regarding conversion between reference systems

Checkout:

GP

for a worked example on IGS08 current epoch to NAD83 2011 2010.0

M

1

thats great! but what if I want to convert the lat lon and height for every sampling interval in a RINEX file?

I don't understand the question - there are no lat/long/heights in a RINEX file.

The transformation between two well defined reference frames like NAD83(2001) and various versions of ITRF can be done with the NGS tool HTDP. It supports batch mode operation. File formats are described on its page at the NGS site. After choosing the reference frames for the input and output coordinates you will also need to see if the epochs for the input and output coordinates. You also must choose a velocity model.

The Canadian transformation tool, TRX, is found here: http://webapp.geod.nrcan.gc.ca/geod/tools-outils/trx.php?locale=en

This is to transform between either XYZ or Latitude, Longitude and ellipsoid height. You cannot use these transformation tools to simultaneously derive an orthometric height.

The orthometric height system in your posting is the new Canadian Vertical datum. There is an excellent web site describing the Canadian vertical system here:

http://webapp.geod.nrcan.gc.ca/geod/hmod/hmod.php#orthometric_height

BTW I recommend reviewing the definitions of various types of heights on this page. Orthometric height as I use it in this reply is not strictly speaking accurate as you will see. Things are rather more complicated.

Like the U.S. NGS the Canadian Geodetic Survey has developed a tool to calculate the geoid height at a specified location. It is here:

http://webapp.geod.nrcan.gc.ca/geod/tools-outils/gpsh.php?locale=en

Finally you mention a desire to perform an epoch-by-epoch transformation of the coordinates in your file. You can create the input file for the tools and do the LLh transformations. As the resolution of most geoid models is one the order of minutes of grid, one geoid-ellipsoid separation value should work for all epochs in your file.

HTH,

DMM

( original post edited to add link to TRX )

Can you explain a little about an epoch-by-epoch transformation? I'm not familiar with that.

Howdy,

In his follow up to his original post he stated: "thats great! but what if I want to convert the lat lon and height for every sampling interval in a RINEX file?"

I interpreted his "every sampling interval" to mean each epoch in his solution file. I then called it epoch-by-epoch perhaps remembering an interesting approach to processing developed by Dr Yehuda Bock of Scripps. See: http://www.geodetics.com/WebSite/papers/GeodeticsPreprint_ION2000.pdf

Sorry for confusing things,

DMM

Not a problem, I'm always interested in learning new things. Thanks for the link.