CSRS-PPP Updates

2024-11-21

National velocity grid for NAD83(CSRS) coordinates epoch transformation updated from NAD83v7VG model to NAD83v80VG model.

2024-11-04

CSRS-PPP updated from v3.54.2 to v4.14.10

• Implemented improved yaw modelling for eclipsing subroutine
• Added the ability to use satellite attitude files
• Improved processing of single-frequency data sets
• Code improvements, cleanup, bug fixes

2024-10-22

• NRCan Final and Rapid GLONASS products (orbits and clocks) have been updated using improved GLONASS products as of 27 November 2022 (GPS week 2238). The filenames of these products have been changed from EMR0DC[A|B]* to EMR0DU[A|B]*.

2024-07-03

• Correction to MTM coordinates reporting in sum and pos files

2024-06-14

• Correction to orthometric height reporting and calculation in pos file
• Correction to orthometric height reporting in CSV file
• Correction to MTM coordinates reporting in sum and pos files

2023-01-09

2022-11-27

CSRS-PPP updated from v3.50.3 to v3.54.2

• CSRS-PPP ITRF solutions for GNSS observations collected beginning on 27 November 2022 (GPS week 2238) will be in the IGS20 reference frame

2022-05-24

CSRS-PPP updated from v3.50.2 to v3.50.3

• Correction in the use of GPS III satellite bias

2022-05-20

Fixed bug in CSV file when reporting lat/lon coordinates starting with +/-0

2021-12-21

CSRS-PPP updated from v3.50.0 to v3.50.2

• Fixed uncertainty scaling bug in static mode for datasets with a non-integer sampling interval slightly shorter than 30 seconds (e.g., 29.9 seconds)
• Fixed RINEX 3 reading bug where constellations with more than 35 signals are discarded

2021-12-15

Correction to epoch added to CGVD2013 orthometric heights

2021-11-04

Correction to calculation of geoid height in ITRF

2021-10-12

Epoch added to CGVD2013 orthometric heights

2021-03-26

Began automatic decimation of high-rate static submissions

CSRS-PPP updated from v3.49.0 to v3.50.0

• Fixed singularities in eclipsing subroutine

2021-02-02

CSRS-PPP updated from v3.46.0 to v3.49.0

• Bug fixes

2020-12-10

CSRS-PPP updated from v3.45.0 to v3.46.0

• Bug fixes

2020-10-27

Correction to calculation of orientation of error ellipse

2020-10-20

CSRS-PPP updated from SPARK v2.32.0 to SPARK v3.45.0

2020-04-07

CSRS-PPP updated from v2.31.0 to v2.32.0

• Fixed bug affecting only single-frequency users tracking multiple signal modulations on the same frequency (e.g., tracking both C1C and C1W)

2020-03-30

Correction to calculation of combined scale factor

2020-01-10

CSRS-PPP updated from v2.26.1 to v2.31.0

• Accepts the following RINEX 3 code modulations for GPS: C2W, C2C, C2L, C2S and C2X
• On-the-fly selection of observables at every epoch as opposed to using constant observables throughout the dataset. Observable-specific biases are handled appropriately.
• Bug fixes in RINEX reader

2019-10-17

Update to CSRS-PPP outputs

• Addition of uncertainties related to epoch transformation
• Correction to calculation of orientation of error ellipse
• Addition of geoid height to sum file
• Decimal year used for epoch in report
• Bug fixes

2019-02-27

CSRS-PPP updated from v2.21.0 to v2.26.0

• Bug fixes

2019-02-14

National velocity grid for NAD83(CSRS) coordinates epoch transformation updated from NAD83v6VG model to NAD83v70VG model.

2018-12-17

CSRS-PPP updated from v2.18.0 to v2.21.0

• Using VMF1 gridded values to compute a priori tropospheric zenith delay (with Final products only)
• Improved stochastic modeling for single-frequency data sets
• Reduced position jumps at day boundaries
• Minor bug fixes

2018-10-11

CSRS-PPP updated from v2.11.0 to v2.18.0

• Added tropospheric gradient estimation
• Removed velocity estimation in kinematic mode
• Modified a posteriori variance factor computation
• Minor bug fixes

2018-08-16

CSRS-PPP updated from GPSPACE v1.05_11216 to SPARK v2.11.0 (2018-07-26)

2017-01-26

CSRS-PPP ITRF solutions for RINEX data obtained after January 28, 2017 (start of GPS Week 1934) will be in IGS14 reference frame.

2016-07-12

CSRS-PPP processing now includes ocean loading corrections for every submission.
Computed with OSO Chalmers grid model (M.S. Bos and H.-G. Scherneck).

CGG2013a (Canadian Gravimetric Geoid 2013 - Version A) is now the default model for the realization of CGVD2013 orthometric heights for NAD83(CSRS) solutions.

2014-09-04

Delay for GLONASS PPP processing reduced from 24 hours to 4.5 hours. NRCan GLONASS orbits and clocks needed for CSRS-PPP processing of RINEX files containing GLONASS observations are now available every 3 hours resulting in a processing delay ranging between 1.5 to 4.5 hours.

2014-03-07

CSRS-PPP updated from v1.05_03812 to v1.05_34613

• Realistic GDOP now reported for all processing and observation selections
• Added high order ionospheric corrections for GLONASS satellites
• Adaptive limits for cycle slip detection and correction now satellite specific
• Introduced ground antenna specific GLONASS linear inter-frequency differential code biases
• Implemented improved yaw modelling for GPS blocks IIA and IIF

2013-11-29

CSRS-PPP updated to report in sum file both CGVD28 and CGVD2013 orthometric heights if estimated position is in Canada. Currently CGVD28 remains the default but can be changed to CGVD2013 on the CSRS-PPP web page.

2013-11-01

CSRS-PPP updated to report in chronological order estimated positions of the pos and csv files for single frequency (L1) processing.

2013-01-07

Updated GNSS processing software from version 05211 to version 03812.

• Use of P2C2 biases for C2 observations processing
• Minor bug fixing and updates of some models

2012-10-19

National velocity grid for NAD83(CSRS) coordinates epoch transformation updated from velgsb_v1.0 model to NAD83v6VG model.

2012-02-14

CSRS-PPP now accepts user provided ocean loading correction files(OTL). This complements the CSRS-PPP database of ocean loading corrections currently available for some regions.

NOTE: A global grid of OTL corrections will soon be added to CSRS-PPP. These default corrections, once implemented, will be sufficient for most PPP applications. For applications very near to the coasts, the optional OTL file will offer a means to use more accurate ocean loading corrections if needed.

2011-10-04

CSRS-PPP can now process GLONASS data. NRCan GLONASS products (orbits and clocks) are available starting on day 0 of GNSS week 1649.

GLONASS precise orbits and clock corrections used for PPP processing are available in 24 hour files (0 to 24 hour) 15 hours after the end of the GNSS day. User submitting RINEX observation files prior to that time will first receive a GNSS only solution. The combined GNSS and GLONASS PPP solution will be performed and sent once the required GLONASS products are available.

2011-08-31

Corrected problem with reported MTM coordinates for a small region of zone 12 (Ontario).

Combined scale now output to mtm file and additional digits added to reported point and combined scales (UTM and MTM). Note that mtm file is now only available for kinematic mode processing.

2011-06-01

CSRS-PPP updated from v1.04_1087 to v1.05_05211

Reporting Updates

• Added plot of 95% horizontal error ellipse
• Added mapping combined scaling factor
• Added plot of tracked number of satellites and epoch carrier-phase ambiguity resets
• Now reporting 95% (2 sigma) error estimates (use to report 1 sigma 67%))
• Changed order of records in .pos and .csv files, now in increasing chronological order for kinematic mode
• Additional decimal added to HH:MM:SS field of .pos and .res (now reads HH:MM:SSS which shifted columns and could affect user's software using fix formats for the pos and res files)
• Cartesian coordinates now output to CSRS-PPP result response e-mail
• Marker name, as defined in RINEX observation file ("MARKER NAME" header record), is now output to PDF report first page just below version number. Name of submitted RINEX file previously found in that location is still available on PDF page footer along with processing time stamp and source of precise orbits and clocks

PPP Computation Products Update

• All clock products (IGS and NRCan) are now 30 seconds resulting in reduced clock interpolation error

Processing Updates

• Tolerance thresholds used for cycle slip detection are now computed based on actual noise of processed data using an adaptive algorithm which reduces likelihood of undetected cycle slips
• Previous cycle slip detection always reset the carrier phase ambiguities for detected cycle slip, now ambiguities are no longer reset if cycle slip detected with enough confidence
• Antenna phase wind-up corrections now applied to moving receiver antenna (kinematic processing mode)
• Tropospheric correction now disabled beyond 40Km above the earth's surface and antenna elevation changed accounted with an exponential model for wet ZPD height decay as proposed by Jan Kouba (Journal of Geodesy, Volume 82, Numbers 4-5, 193-205)
• Since April 17, 2011 estimated ITRF coordinates are provided in the IGS08 reference frame (IGS08 is the IGS realization of ITRF2008)

2009-11-25

CSRS-PPP NAD83(CSRS) coordinates now available at user defined epochs. In addition to the 1997, 2002 and GNSS observation epochs, coordinates can be obtained for any user defined epochs between 1994 and the current date.

2009-09-09

CSRS-PPP coordinates now available at the epochs of the adopted NAD83 realisations

A method to transform coordinates between NAD83 realisations has been developed and implemented. Testing using PPP coordinates for 12 Canadian stations computed from 1-day sessions at quarterly intervals over a 7-year period indicate that the transformation, based on a national velocity grid, has centimetre-level accuracy or better.

The CSRS-PPP on-line application has been modified to allow users to select a particular NAD83 realisation and transform epoch coordinates accordingly. The output reports remain largely unchanged except for the clarification of the output epoch and, if it differs from the epoch of the GNSS data, the addition of Table 3.4a in the "sum" report. This new table lists the differences in PPP coordinates between the epochs of the GNSS data and the selected one.

2009-05-18

UTM and MTM (3 degree zones) coordinates -- along with the associated hemisphere, zone and scale -- are now output in the .sum, .pos (for UTM) and .mtm (for MTM) CSRS-PPP output files. UTM are always output and MTM only if the NAD83(CSRS) reference frame is selected.

A CSRS-PPP queue was implemented to automatically process and e-mail results of RINEX files for which GNSS orbits and clocks are not available at the time of submission. In the case of multiple RINEX zipped submissions, RINEX files for which the orbits and clocks are available will be processed and results e-mailed without delay as usual. Only those RINEX files for which the orbits and clocks are not yet available will be queued.

2008-05-12

The user-wait period for CSRS-PPP processing has been reduced by a factor of 10, from 17 to 1.5 hours, counted from the hour of the last observation in the submitted dataset. This improved timeliness is a result of NRCan`s precise orbit and clock products being updated within 90 minutes of the time the most recent hourly GNSS tracking data files become available from the global IGS network.

Using absolute antenna phase centre calibration for receiver and satellite antenna for RINEX observation data on and after November 5, 2006. For data prior to that date relative phase centre calibration of receiver antenna and nominal offsets for satellite antenna are used. If receiver antenna is missing from calibration file, nominal offsets for satellite antenna are used instead of absolute calibration.

Replaced Niell tropospheric mapping function (NMF) by the Global mapping function (GMF) based on the European Centre for Medium-Range Weather Forecasts (ECMWF) numerical weather model.

2008-05-12

Bug Fix

Corrected problem affecting RINEX observation files with more than 9 observation types and requiring 2 "# / TYPES OF OBSERV" RINEX file header lines.

2006-12-05

Added a multi RINEX file submission option. All RINEX observation files will be processed independently and must be included in a zipped(.zip) archive. All observation files will be processed with the same CSRS-PPP selected reference frame (NAD83-CSRS or ITRFnn) and mode(static or kinematic). The zipped archive is submitted to CSRS-PPP as a regular RINEX observation file and can contain a mix of uncompressed or Hatanaka, zip, gz and Z compressed files. A single e-mail is returned. It contains a URL link to the zipped archive of individual CSRS-PPP results as well as individual processing summary tables.

The postscript (ps) graphical report is no longer included in the returned CSRS-PPP solution zipped archive.

2006-10-13

Added CGVD28 (HTv2.0) orthometric heights to the CSRS-PPP csv output file for kinematic mode processing.

2006-10-06

Added the CGVD28 (HTv2.0) orthometric height to the CSRS-PPP output. The orthometric height is obtained from the GNSS derived ellipsoidal height using geoid undulation and correction computed with GSD's GPS-H.

2006-06-01

Corrected application of phase terms in ocean tide loading model.

Corrected Neill tropospheric mapping function sign error affecting southern latitudes computations (9mm in height).

Corrected incorrect sign reporting for latitudes between 0 and 1 degree south.

2004-09-01

Addition of a comma separated position file to facilitate GIS input.

2004-03-24

Improved robustness of processing for RINEX files containing comments inside data blocks and for cases when generation of plots to be included in the ppp_solution.ps report failed.

Improved robustness of RINEX files decompression.

Implemented proper exit on empty observation files.

Implemented a new release of GNSS processing engine with following features: increased size of estimated elevation field in ".pos" output file; corrected problems with ionospheric model interpolation needed for single-frequency (L1) processing and improved robustness for RINEX GNSS observation files containing 1 millisecond (ms) jumps in either the time tags or GNSS observations.

2003-12-17

Bug Fix

Corrected a problem resulting in some valid RINEX Observation data being mis-identified as RINEX Navigation data and consequently rejected.

Corrected a problem causing some older datasets (pre 2000) not to process successfully. Note that although pre October 28, 2000 datasets should now process properly, only data at an interval of 15 minutes, measured from 0hour UT, will be processed since IGS 5 minute clock products are not available prior to that time.

2003-12-08

Improved ionospheric model for single frequency data processing

Increased apriori standard deviation of pseudo-range observations from 1.0m to 2.0m and from 1.0cm to 1.5cm for carrier-phase observations to mitigate problems with noisier datasets

2003-11-12

Corrected problems of incorrectly estimated coordinates when "Select Reference System" option set to "NAD83" (GPS Processing Engine Version 1.1)

2003-10-14

Public Release (GPS Processing Engine Version 1.0)