数据准备阶段利用Gamit下载数据
- 精密星历下载：（放在igs文件夹中）精密星历不同阶段产品开头为:igu ,igr,igs
sh_get_orbits 可获得帮助
超快速星历(IGU星历,每天4次[3-9-15-21]) -pre u <f/r/u>的意义即在于此
快速星历(IGR星历, 17小时) -pre r
精密星历(IGS星历, 13~20天) -pre f
精密星历sp3文件：sh_get_orbits（cddisa.gsfc.nasa.gov服务器好使）
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Get ORBIT files from CDDIS and other archives
Usage: sh_get_orbits -archive <archive> -yr <yr> -doy <doy> -ndays <num> -multiday
-type <type> -pre <f/r/p> -center <center> -gnss [gnss-code]
-makeg <yes/no> -maket -noacc -eop_ser <ser> -eop_pth <pth>
-orbt <orbt> -ftp_prog <ftp/ncftp/wget> -max_fit_tol <val>
Where: <archive> Either sopac, cddis, mit, or igscb [Defautl cddis]
<yr> 4 char year of nav data requested [Required]
<doy> 3 char day of year of nav data requested [Required]
<num> Number of consecutive days of data to retreive [Default 1]
<multiday> Form a multiday t-file from downloaded files
<type> Either sp3 or gfile (gfile from sopac only). [Default sp3]
<f/r/u> The precision of the orbit requested. [Default f]
where f=final, r=rapid, u=ultrarapid (includes prediction)
<center> Name of the IGS processing center sp3 files. [Default igs]
available centers igs/cod/emr/esa/gfz/jpl/ngs/sio/mit
<gnss-code> G R E C I J [Default G]
<makeg> Convert sp3 files in GAMIT format g-files files. [Default yes]
<noacc> Do not exclude satellites base on accuracy codes. [Default exclude]
<ser> This is the pole. and ut1. series to be use when converting
sp3 -> g-files. ONLY use when makeg = yes. [Default usno]
<pth> This is the path to the pole.ser and ut1.ser files [Default ~/gg/tables]
<orbt> 4 char ID used in g-file name [Default 3 char center + 1 char pre. Ie igsf]
<ftp/ncftp/wget> choose the ftp program to be used [default is ftp]
<val> maximum misfit given in meters before a satellite is removed from orbit fit
makeg make a gamit g-file from downloaded SP3 file [default yes]
maket make a gamit t-file from downloaded SP3 file [default not to make]
NOTE: IGS sp3 files are available in f/r/p precision from both sopac and cddis archives
SIO sp3 files are available in r/p precision ONLY from sopac archive
All other sp3 files are ONLY available in f precision form both cddis and sopac
NOTE: igsf orbits downloaded from cddis between weeks 730 and 1459 will get the repro1
orbits which are renamed from ig1 to igs. To get original igsf orbits use sopac
or igscb for archive
Examples: sh_get_orbits -archive sopac -yr 1998 -doy 235 -ndays 1 -type gfile -pre r
sh_get_orbits -archive cddis -yr 1998 -doy 235 -ndays 1 -pre r -center sio
sh_get_orbits -archive cddis -yr 1998 -doy 235 -ndays 7 -ftp_prog ncftp
sh_get_orbits -archive mit -yr 2000 -doy 235 -ndays 7 -center mit
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2.广播星历下载（放在brdc文件夹中）下载融合后的星历;一般是以brdc开头的
sh_get_nav
sh_get_nav (cddisa.gsfc.nasa.gov服务器好使)
[1] ftp://garner.ucsd.edu/pub/rinex/YYYY/DOY/ (以auto开头的文件，下载后改为brdc开头，也有说可以不用改)
[2] ftp://cddisa.gsfc.nasa.gov/pub/gps/data/daily/YYYY/brdc/ （以brdc开头）
[3] ftp://igs.ensg.ign.fr/pub/igs/data/YYYY/DOY/ （以brdc开头）
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Get RINEX navigation files from SOPAC or CDDIS archives
Usage: sh_get_nav -archive <cddis/sopac> -yr <yr> -doy <doy> -ndays <num> -rxobs -allnav -ftp_prog <ftp/ncftp>
<archive> Either sopac or cddis [Default sopac]
<yr> 4 char year of nav data requested [Required]
<doy> 3 char day of year of nav data requested [Required]
<num> Number of consecutive days of data to retreive [Default 1]
<rxobs> Retreive nav files from RINEX observation day directory
archives rather than RINEX navigation file archives. [Default no]
<allnav> Retreive all nav files, NOT only combined brdc or auto files. [Default no]
<ftp/ncftp/wget> select ftp program to use [default is ftp]
Examples: sh_get_nav -archive sopac -yr 1998 -doy 235 -ndays 1 -ftp_prog ncftp
sh_get_nav -archive cddis -yr 1998 -doy 235 -ndays 7
sh_get_nav -archive sopac -yr 1998 -doy 235 -ndays 7 -rxobs
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4.IGS观测站数据下载（放在rinex文件夹下），有些站在某些服务器上没有,需要从多个服务器下载数据;若下载得到的是压缩格式的d文件,需用gamit软件提供的 crx2rnx命令进行格式转换;
sh_get_rinex
[1]ftp://garner.ucsd.edu/pub/rinex/YYYY/DOY/ （d文件，下载后用crx2rnx 解压）
[2]ftp://cddisa.gsfc.nasa.gov/pub/gps/data/daily/YYYY/DOY/YYo/
[3]ftp://igs.ensg.ign.fr/pub/igs/data/YYYY/DOY/ （d文件，下载后用crx2rnx 解压）
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Get RINEX observation files from one or more open archives in tables/ftp_info
Currently supports at least:
CDDIS, SOPAC, IGN-IGS(igni), IGN-Europe (igne), BKG-IGS (bkgi), BKG-Europe(bkge), TIGA
EPNCB, IPGP, NOA, OLG Austria (olg/olgr), GEODAF, ICC Geofons (icc), KREIZ, GPSCOPE
UNAVCO, NGS CORS (cors), USNO, PANGA, WCDA
Geosceince Australia (geoaus), GeoNet New Zealand (geonz), KASI
Usage: sh_get_rinex -archive <archive> -yr <yr> -doy <doy> -ndays <num> -sites <sites>
-ftp_prog <ftp/ncftp/wget> -list -sd <sites.defaults dir> -expt <expt> -nouncompress
-subdir
<archive> One or more archives specified with a 'rinex directory' entry in ftp_info [Default sopac]
<yr> 4 char year of nav data requested [Required]
<doy> 3 char day of year of nav data requested [Required]
<num> Number of consecutive days of data to retrieve [Default 1]
<sites> List of sites to be retrieved from the ftp archive [Required]
<ftp/ncftp/wget> select the ftp program to be used [default ftp]
<list> get list of available files from selected archive
<xcheck> do not ftp rinex data if xfile exists already [defaul N]
<sites.defaults dir> directory where sites.defaults located
<expt> experinent name used to interogate the sites.default file
<nouncompress> do not uncompress the files
<subdir> creates a temporary subdirectory to speed up uncompress when there are many rinex files in directory
Examples: sh_get_rinex -archive sopac cddis -yr 1998 -doy 235 -ndays 1 -sites algo drao ankr
sh_get_rinex -archive cddis -yr 1998 -doy 235 -ndays 7 -ftp_prog ncftp
sh_get_rinex -archive cddis -yr 1998 -doy 235 -ndays 7 -ftp_prog ncftp -xcheck Y
sh_get_rinex -archive sopac -yr 1998 -doy 235 -list -subdir
sh_get_rinex -archive sopac -yr 2000 -doy 185 -sd ../tables/sites.defaults -expt medi
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