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You are provided with the original raw file (15762380.t00) and log sheet
(04LF_2014-242.pdf) from the occupation of a survey mark, during which the
tripod was disturbed. This experiment demonstrates how to use track to find the
epoch of disturbance and truncate the RINEX file to prevent propagation of bad
data during data exchange and other processing.

All executable commands have a dollar symbol ($) as the first character.


1. Translate Trimble raw file to RINEX

 a. Run runpkr00

$ runpkr00 -g -adeimv 15762380.t00 04lf2380
$ ls 04lf2380*

 b. Run teqc

$ teqc +nav 04lf2380.14n +obs 04lf2380.14o -tr d 04lf2380.dat
$ ls 04lf2380*

   Note that this raw file covers several days, due to the way the receiver
   was set up, but the log sheet only covers the period


2. Find the approximate position and a nearby continuous site

$ teqc +qc -nav 04lf2380.14n 04lf2380.14o

   Read 04lf2380.14S and view in Google Earth. You will find that the site is
   located on the northern edge of Maxwell Farms Regional Park just off Verano
   Avenue in Sonoma, California. This area has many continuous GNSS sites in the
   Plate Boundary Observatory (PBO) network, so look for nearby sites at
   http://pbo.unavco.org/. You will find that P199 is the nearest site, about
   5 km to the south-west. We will therefore use P199 as our reference site.


3. Download RINEX files for the reference site and IGS final orbits

$ sh_get_rinex -archive unavco -yr 2014 -doy 238 -ndays 2 -sites p199
$ sh_get_orbits -orbit igsf -yr 2014 -doy 238 -ndays 2 -nofit

   Concatenate the files into one for input to track

$ teqc -phc p2612360.14o p2612370.14o +obs p261236-70.14o
$ cat igs18070.sp3 igs18071.sp3 > igs18070-1.sp3


4. Create a basic track command file

 a. Define input RINEX files

$ cat << END > track.cmd
 obs_file
  p261 p261236-70.14o F
  6908 69082360.14o   K

END

 b. Define input orbit files

$ cat << END >> track.cmd
 nav_file igs18070-1.sp3 SP3

END

 c. Define the type of experiment ("long" for baseline length > 1 km)

$ cat << END >> track.cmd
 mode long

END

 d. Define a priori coordinates (from .apr-file or sh_rx2apr) and constraints

$ cat << END >> track.cmd
 site_pos
  p261 -2677432.92612 -4248806.23641  3918882.09941   -0.01961    0.01519    0.00248 2011.4110
  6908 -2669573.2959  -4253294.9698   3919133.7752

 site_stats
  6908  0.01 0.01 0.01  1 1 1

END

 e. View log sheet to calculate equipment configuration and antenna height

Receiver: Trimble 5700 ("C"-type from ~/gg/tables/rcvant.dat)
Antenna:  Trimble Zephyr Geodetic (IGS code TRM41249.00; see
          ftp://igs.org/pub/station/general/antenna.gra or
          https://www.ngs.noaa.gov/ANTCAL/ for dimensions)

Information for P199 may be obtained from the master station.info file for the
dates to be processed:

$ grep '^ *P199' ~/gg/tables/station.info

Antenna height is:

$ echo '110.25 110.20 110.30' | awk '{slbgp=($1+$2+$3)/3; dhbgp=sqrt(slbgp^2-16.981^2); dharp=dhbgp+0.891-5.326; printf "%.4f\n",dharp/100}'
$ cat << END >> track.cmd
 ante_off
  p199  0.0000 0.0000 0.0083  TRM29659.00     SCIT  C
  04lf  0.0000 0.0000 1.0450  TRM41249.00     NONE  C

 antmod_file ~/gg/tables/antmod.dat

END

 f. Add some explicit controls on input data and output files

$ cat << END >> track.cmd
 interval 30

 use_gptgmf 0.5

 back_type smooth

 pos_root 04lf
 res_root 04lf
 sum_file 04lf.sum

 out_type DHU

END


5. Run track and plot results

$ track -f track.cmd >& track.log
$ sh_plot_track -f 


  Michael Floyd (2018-06-21, MIT)

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