GAMIT 10.71版本已于2020年3月9日在官网中发布，更新内容如下：

- The radiation pressure model is expanded from 9 to 13 parameters, adding two

  twice-per-revolution (2/rev) and two 4/rev terms. GAMIT will carry all 13

  parameters, designated "ECOMC" (for Empirical CODE Models 1 and 2 combined) in

  tables/sestbl. In generating fits to the IGS orbits, we recommend using ECOMC

  (the default). Note that if you estimate orbits in GAMIT ("RELAX." in

  tables/sestbl.) you cannot mix in GLOBK the 10.71 processing with pre-10.71

  processing that uses the 9-parameter (BERNE or ECOM1) models. When combining

  regional processing with MIT or SIO global h-files, you should always run

  GAMIT without orbit estimation ("BASELINE" in tables/sestbl.), as we have long

  recommended. Even with the same version, different choices of orbit modeling

  parameters are likely to make the MIT combined binary-files incompatible with

  recently processed. If BASELINE model is used in the GAMIT processing, the

  incompatibilities will be minor but in RELAX mode they can be severe (high

  chi^2 increments). Removing all "apr_svs", "mar_svs", "apr_rad" and "mar_rad"

  options in the GLOBK command file should minimize the effects of

  incompatibilities.

- Beidou processing now uses L6/C6 (B3 at 1268.53 MHz) rather than L7/C7 (B2b at

  1207.140 MHz) as the lower-frequency observable to accommodate the tracking

  configuration of most of the current GNSS receivers providing public data.

  Based on a sampling of 230 RINEX files from the archives, about 50% include

  only L6/C6 compared with about 5% that include only L7/C7. The higher-

  frequency observable will remain L2/C2 (B1-2 at 1561.098 MHz) since very few

  of the public RINEX files contain L1/C1 from the B1 at 1575.42 MHz transmitted

  by BDS 3 satellites. If L7/C7 is the only observak present (i.e, no L6/C6),

  GAMIT will try to process the data along with L7/C7 receivers but there may be

  ambiguity resoluion issues. User should data files and process only those

  sites with the same frequency data.  There are still some issues with clock

  estimates for Beidou data and pre-fit edting in autlcn.

- The default tables/sestbl. now has the 2nd-order ionosphere model turned on.

  The IGSG IONEX files will be used by default. If processing near-real time,

  the "-ion igrg" option should be used with sh_gamit. We also recommend always

  including the "Inertial Reference System" option (current default "IAU0A")

  explicitly.

- tables/svnav.dat is now linked to the IGS satellite metadata SINEX file

  (igs_metadata.snx). Release 10.70 and earlier versions of GAMIT cannot read

  this file format and svnav.dat needs to be linked to svanv.dat.allgnss, which

  will be maintained for the foreseeable future. Several changes to files in the

  tables/ directory may be incompatible with early versions of GAMIT.

- The tables/station.info file now accommodates another optional column

  ("AntDAZ" in the header line) to specify the azimuth (clockwise from true

  north) of the antenna. Conventionally antennas are aligned with true north but

  some (and likely many others that we don't know about yet) are recorded as set

  to another azimuth. The "AntDAZ" azimuth is read to rotate the phase center

  offsets (PCOs) and phase center variations (PCVs) from the ANTEX file

  (tables/antmod.dat) to correct for the azimuth of the antenna. sh_upd_stnfo

  can extract this information from IGS log files if the AntDAZ header is

  included (users should ensure that there are no non-numeric values in the

  columns below AntDAZ; white space in OK). The IGS will not implement this

  feature until ITRF2020 is released (that is, it will be part of repro3 but not

  the operational processing).

- We have changed many symbolic links in tables/ to be relative, rather than

  absolute, which assume that users install a local GRIDS/ directory at the same

  level as the source code (e.g. gamit/, libraries/, kf/, maps/, tables/, etc.),

  where grids downloaded from ftp://everest.mit.edu/pub/GRIDS/ should be stored.

  Creation of specific symbolic links, e.g. atml.grid, map.grid, met.grid, by

  the user to the corresponding grid files is then no longer necessary.

- sh_gamit now will remake g-files from SP3 files each time it is run to ensure

  that the orbit models in tables/sestbl. are consistent with the sh_sp3fit

  models (these models are now read from sestbl. provided a copy can be found in

  the standard processing directories). For sub-network processing, g-files

  should be made once before proceeding to process each sub-network (assumed to

  be in parallel) using the "-remakeg N" option used with sh_gamit.

- We remind users that when processing GLONASS data the ambiguity free (.glr) 

  binary h-files should be used in GLOBK. Also remember that a multi-GNSS orbit

  file should be used as well.

- The format for the "apr_svs" and "mar_svs" radiation parameters specification

  in the GLOBK command file has changed, with the unused "zrad" and "xrad"

  entries removed (see Pre 5.32 and Post 5.32 discussion in help/globk.hlp). The

  options using the "<nn.nn>R" format remains unchanged. Older globk commands

  with explicit radiation parameter constraints and process noise may need to be

  updated.

- GLOBK has moved to using "<GNSS><SVN>_<PRN>" syntax for satellite identifiers

  in output files (e.g. the .org-file), where <GNSS> is G, R, E or C, and SVN

  and PRN are Satellite Vehicle Number and Pseudo-Random Noise code,

  respectively. For GPS, the default is still PRN<PRN>_<SVN>. The new format for

  GPS can be invoked with the "use_prn n" command near the top of the command

  file. (See help/globk.hlp.)

- New wild card features in file names now allow dates and times to be used

  based on the date and time of the h-file being processed. (See 5.32 features

  in help/globk.hlp.)

- GLOBK can now do reference frame realization in back solutions. This will

  happen automatically if GLORG is invoked in a GLOBK command file with the

  "bak_file" option included.

- We will no longer provide GMT .grd-files in the maps/ directory to reduce the

  size of the archive (.tar) files. Instead we now provide a new script,

  sh_dem, which will download and create a local copy of a chosen digital

  elevation model (DEM) over a geographic region, both selected using the script

  options. The script is now called by sh_plotvel if the "-topo", "-topo_file"

  and/or "-illu_file" options are used; if the latter is given without an

  argument, sh_plotvel will create a .grd-file of the gradient for plotting

  shaded-relief (illumination) from the topographic .grd-file named or created

  with the "-topo_file" option. Both sh_dem and sh_plotvel require GMT to run.

- GMT version 6.0.0 was released in November 2019. Scripts in com/ that use GMT

  to produce plots were updated for GAMIT/GLOBK 10.6 to accommodate major

  changes in the syntax of GMT version 5 commands (see relnote.10.6); the old

  scripts, using GMT 4 syntax, are still available in com_preGMT5/ but are no

  longer maintained. Although we have not done extensive testing yet, we

  understand that GMT 6 is fully backwards compatible with GMT 5 (e.g.

  https://docs.generic-mapping-tools.org/6.0/migrating.html) and should work

  seamlessly with our scripts currently in com/, which explicitly call "gmt"

  (now the sole GMT executable) throughout.

- We have become aware that the GMT installation available via the software

  repository for Ubuntu 16.04 LTS does not include the supplemental programs,

  most significantly psvelo for GAMIT/GLOBK. We recommend upgrading your

  Ubuntu operating system or building GMT from source. See

  https://gmt.soest.hawaii.edu/projects/gmt/wiki/Installing#Linux and our "Known

  Issues" web page at http://geoweb.mit.edu/gg/issues.php for more information.

- We have also become aware that there seems to be an issue with the

  implementation of gfortran version 7 on at least Ubuntu 18.04 LTS and openSUSE

  Leap 15.1 operating systems, resulting in failed compilation with segmentation

  fault error messages, including "See <file:///usr/share/doc/gcc-7/README.Bugs>

  for instructions." We recommend upgrading to another version of gcc/gfortan,

  or downgrading to gcc/gfortran version 6. See our "Known Issues" web page at

  http://geoweb.mit.edu/gg/issues.php for more information.

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Summary of specific changes for 10.71 (by directory):

- com/

links.arc, links.com, links.day: Updated to link otides.dat and to avoid linking

                                 the old ephemeris files (soltab., luntab.,

                                 nutabl.) if ~/gg/tables/nbody exists. Fixed

                                 typos.

sh_cleanup: Added missing closing curly bracket in test to remove n-files on

            lines 386 and 387. Floyd/Pickle 190507

sh_gamit: Revert to using GPS-only RINEX 2 instead of MGEX RINEX 3 nav files

          when processing GPS data since sh_rx2apr (svpos/svdiff) doesn't yet

          recognize RINEX 3.

          Fix bug in naming files for -jclock sp3 option.

          Fixed a typo in call to sh_setup causing the lfile not to be updated

          from the .apr-file.

          Correct version number - now 10.70 2019/8/14.

sh_get_orbits: Placed $noclean variable in quotes in if-test at end to ensure a

               string match rather than interpretation as a test, which causes

               an error.

sh_glred: Removed debug statement that forced archiving of the binary h-files.

sh_hector: Minor edits to some awk commands.

sh_makex: Initialize the sp3file variable to avoid a problem when running stand-

          alone.

sh_otlcmc: New script to create tables/otlcmc.dat file from .cmc-files at

           http://holt.oso.chalmers.se/loading/CMC/.

sh_plot_elmean: Updated color scheme to work with GMT 5. Small changes to line

                widths.

sh_rx2apr: Updated grep commands to select only records that begin with a space

           before the site ID, ignoring any "EXTENDED" records that may be in

           the .apr file.

sh_sp3fit: Fix bug in writing model names for the ARC input file.

sh_tshist: Updated script to fully implement pos_res type. Original only

           partially updated from com_pre5GMT version.

sh_upd_stnfo (and kf/htoglb/mstinf.[fh]): Added -debug option to help diagnose

                                          problems with bad year in IGS logfiles

                                          and fixed a bug associated with first

                                          antenna starting after the first

                                          receiver entry.

sh_update_dcb: Added explicit internal test for presence of tables/svnav.dat,

               needed for gamit/utils/dcbtab2.

sh_update_eop: Updated to circumvent the shutdown of maia.usno.navy.mil and

               toshi.nofs.navy.mil from 2019-10-24 to 2020-04-30.

- gamit/

orbits/kouba_gps.f, orbits/oversn.f; arc/ertorb.f, arc/earthradTUM.f,

  arc/aversn.f; lib/gpsblock.f, lib/lversn.f: Updated for Block IIIA SV.

                                              WARNING: Will recongize GPS Block

                                              IIIA but use IIF values for Earth

                                              radiation pressure and yaw.

arc/satprop.f, arc/earthradTUM.f: Updated for Block III SV. Temporarily use IIF

                                  Earth radiation model for Block IIIA for NCLE1

                                  (set for TUM1) and remove debug print from

                                  earthradTUM.f.

arc/sbfn: Fix bug in effect of General Relativity on satellite (~8 mm over 24

          hrs).

includes/makex.h, lib/rrinex.f: Increase maximum line length to 1024, and

                                associated maximum observables allowed in

                                rrinex.f and "MAXOBT" in makex.h to 63, to

                                accommodate long records in RINEX 3 files.

lib/clkera: Erroneous extra read of "clkoff", apparently a problem with Intel

            compiler but not gfortran.

lib/linear.f, model/get_antinfo.f, model/get_antpcv.f, model/get_svantpcv.f:

                          Fix problem with interpolation of elevation-only PCVs.

lib/rrxhed.f: Skipped reading of SV-dependent wavelength factors in a RINEX

              header since this feature is not yet supported.

lib/sel_obtyp.f: Fix problem with omitted Beidou observable.

                 Remove debug print statements.

makex/get_navclk.f: Fix bug in not recognizing GNSS code "I" on the nav file.

makex/getsp3.f: Added test for sp3d format.

makex/rbatch.f: Add trap for "numsit" > "maxsit" in new-format case.

                Correct fix of trap for "numsit".

makex/mversn.f, model/j_from_sp3.f, model/getnav.f: Allow reading sp3 "d" and

                                                    fix getting the program name

                                                    for warning/fatal messages.

makexp: Assign the sp3 file name when running manually.

        Revoked Zou/King 180912 update and reverted to version 9.86.

        Added correct handling of SP3 file name when running manually.

model/call_mag.f, model/iondel.f, model/mag13.f, model/setup.f; fixdrv/bmake.f;

  tables/sestbl.: Added IGRF13 magnetic field model and changed default from

                  IGRF12 to IGRF13

model/setup.f: Fix frequency check so that it works for L1-only.

model/update_coords: Add missing "debug" in call to get_antinfo.

utils/metutil: Change linear interpolation routine to be scalar rather than

               vector.

- help/

displace.hlp: Updated documentation.

- kf/

blsum/tscon.f: Added assumption that UNR/NGL .txyz2 files without a reference

               frame explicitly in the file name are the latest IGS14 version.

displace: Updated Makefile, grid calculations and added tensile component to

          calculations.

gen_util/name_to_block.f: Changes BLOCK III to BLOCK IIIA so that correct

                          satellite number is assigned to the new PRN03.

gen_util/real_stats.f: Updated dimensioning and bounds checking. Very long time

                       series could cause segmentation violations.

gen_util/sp3_lib.f, includes/sp3_def.h: Updated maximum number of nadir angles

                                        values and added a dimensioning test.

gen_util/sp3_lib.f: Fixed bug in report_stat call that is invoked in updated

                    sp3_def.h is not used. Increased max nadir values to 41 for

                    Galileo chamber calibrations.

globk/read_glb_mar.f: Critical update needed to make the SOURCE command work.

glout/write_iers.f: Updated formats to allow more than 99 reference frame sites.

htoglb/mstinf.[fh] (and com/sh_upd_stnfo): Added -debug option to help diagnose

                                           problems with bad year in IGS

                                           logfiles and fixed a bug associated

                                           with first antenna starting after the

                                           first receiver entry.

track, gen_util/sp3_lib.f: Updated for Beidou B7 phase and range measurements.

utils/corcom: Updated output formats to allow for fast ice velocities.

utils/glbtog.[fh]: Fixed bugs with writing G-files for non-GPS systems.

libraries/

comlib/proper_runst.f: Removed need for trailing "/" in HELP_DIR definition.

- tables/

luntab.2020.J2000, soltab.2020.J2000, nutabl.2020: Added luni-solar tables for

                                                   2020 from JPL DE200.

antmod.dat: Now linked to an IGS14 rather than IGS08 ANTEX file, which is no

            longer updated by the IGS for new launches. As noted in

            relnote.10.61, this will create a 2-3 mm discontinuity in height for

            all antennas and 5-10 mm discontinuities in horizontal and height

            for about 20 antennas.

            Updated regularly to the latest IGS14 ANTEX file (currently

            igs14_2091.atx, as of the date of this release). Linked from

            2019-10-10 (GPS week 2074) onwards to the IGS14 ANTEX file

            supplemented with calibrations provided by the National Geodetic

            Survey (NGS) (currently ngs14_2091.atx), plus some additional

            entries copied from similar records to accommodate antennas without

            any official calibrations. tables/antmod.dat is linked to

            tables/ngs14_2091_plus.atx, at the time of this release.

            Updated GLONASS SVs R801, R802, R855, R856, R858 and R859 to match

            extended IGS designations (K1A, K1B and M+) in

            tables/igs_metadata.snx.

igs14_comb_na17.apr: Added new North America plate reference frame ("NA17")

                     based on Kreemer et al. (2018).

ftp_info: Updated vmf1 address and directory according to change reported by

          Johannes Boehm in IGS-ACS email #1176.

          Added HartRAO IGS regional data center and JAXA data center.

globk.cmd: Added inclusion of apr_tran by default and option for apr_rot when

           using SINEX files.

           Corrected erroneous "COMB out_glb" output file name to ensure

           "------" string is parsed properly by prepending "H" to file name.

leap.sec: Extended limit of table to 31 December 2020 with no additional leap

          seconds, following to IERS Bulletin C 59.

hi.dat: Added TRM159800.00 antenna.

igs_metadata.snx: Added from http://mgex.igs.org/ (currently

                  igs_metadata_2091.snx, as of the date of this release) and

                  augmented with a bespoke block for the yaw of each satellite,

                  currently read from tables/svnav.dat with some assumptions for

                  some satellites and systems.

rcvant.dat: Fully updated to match IGS codes for all receivers and antennas,

            following ftp://igs.org/pub/station/general/rcvr_ant.tab. Records of

            other known antennas, from the old rcvant.dat and those in the NGS

            ANTEX file (see description of antmod.dat, above), are added. The

            14th character, indicating support for the receiver or antenna in

            GAMIT, is updated to identify the source of antenna calibration. See

            header for more information.

svnav.dat: Metadata for GLONASS (R), Galileo (E), Beidou (C), IRNSS (I) and QZSS

           (J) fully updated to match tables/igs_metadata.snx (from

           http://mgex.igs.org/), which will ultimately supercede

           tables/svnav.dat; metadata for GPS assumed to be good (will be

           verified ultimately).

otlcmc.dat: Replaced the provisional center-of-mass corrections for FES2012 with

            new official ones from H. G. Scherneck. The differences are less

            than 0.05 mm.