Radio Technical Commission for Maritime Services The State

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Radio Technical Commission for Maritime Services The State and Status Special Committee – 104

Radio Technical Commission for Maritime Services The State and Status Special Committee – 104 20 March, 2014 NOAA March 2014 NOAA / NGS RTN Webinar Kendall Ferguson Hemisphere GNSS, Senior Principal Design Engineer RTCM, SC-104 Chair & Board of Directors Stafford, VA USA

Presentation Outline • Question Often Asked – Why is RTCM, an apparent maritime-based organization,

Presentation Outline • Question Often Asked – Why is RTCM, an apparent maritime-based organization, involved in carrier-based real-time GNSS provider networks? • Existing Standards: State and Work In Progress – The current standards – Work in progress – New work on the horizon • Summary

Two Main Message Standards • RTCM 2. 3 (RTCM 10402. 3) – Codephase Differential

Two Main Message Standards • RTCM 2. 3 (RTCM 10402. 3) – Codephase Differential Corrections • Primarily L 1 -Only, GPS-Only (though there is some support for GLONASS) – For SOLAS applications • Message format developed with primary communication link layer in mind – MF/LF Band at 25 -300 bps • Typical Accuracies < 1 m • Yes, RTCM 18 -21 support carrier applications but these are not SOLAS • RTCM 3. 2 (RTCM 10403. 2) – Carrier and Code Differential Corrections for High-Precision • For RTK, Network RTK, and PPP-type applications • Recently modernized with, so called Multiple Signals Messages (MSM), for generic inclusion of new constellations and signals • MSM Currently supports GPS, GLONASS, Galileo, QZSS, Bei. Dou, SBAS – Though some work still in progress for newer constellations and signals • Message structure designed with OSI 7 -layer architecture in mind

Standards Work In Progress • RTCM 10402. 3 (i. e. , Version 2. 3)

Standards Work In Progress • RTCM 10402. 3 (i. e. , Version 2. 3) Version 2. 4 – Multi-GNSS/Multi-Frequency (i. e. , DGNSS). • Via new generic messaging approaches (e. g. , Type 41 and 42). – Potential for 2 dm 2 σ (at max broadcast range). – Supports Legacy Message Interleave (e. g. , Type 1 and 9). – Recommending Retirement of Types 18 -21 • RTCM 10401. 2 (i. e. , RSIM 1. 2) RSIM 1. 3 – Defining Reference Station (RS), Integrity Monitor (IM), Control Station (CS) and Transmitter (TR) Performance, Functions, and Messaging for SOLAS DGNSS Applications. – Modernizing from L 1 GPS only to Multi-GNSS/Multi-Frequency – Adding further Alarm Attributes to Aid in Monitoring and Reporting of Alarm Conditions • Reduce Load on Control Station Operators • Speed System/Component Failure Detection and Recovery

Standards Work In Progress (continued) • RTCM 3. 2 – Version 3. 2 Published

Standards Work In Progress (continued) • RTCM 3. 2 – Version 3. 2 Published February 1, 2013 • Mostly to collect the numerous revisions to Version 3. 1 • These 3. 1 updates include: – First Multiple Signals Messages (MSM) – First State Space Representation (SSR) Messages – MAC and FKP Messages – Amendment 1 (Published July 12, 2013) • Added Bei. Dou Multiple Signals Messages (MSM) • Added Galileo F/Nav Ephemeris Message – Amendment 2 (Published Nov 7, 2013) • Added QZSS Multiple Signals Messages (MSM) • Added QZSS Ephemeris Message

Standards Work In Progress (continued) • RTCM 3. 2 (Work In Progress) – State

Standards Work In Progress (continued) • RTCM 3. 2 (Work In Progress) – State Space Representation (SSR), a message for PPP-type uses • Phase I: already in published 3. 2 • Phase II: adding additional models such as TEC (in progress) • Phase III: carrier based clocks (in early development states) – Coordinate Transformation Messages improvements underway – Network RTK Approaches (i. e. , Non-Physical Reference, MAC, and FKP) • Currently GPS and GLONASS only • Committee currently deliberating adding other constellations and signals – Navigation Data Frame (NDF) messages under deliberation • Carries raw navigation data frames from various satellites: – GPS, GLONASS, Bei. Dou, QZSS, and SBAS.

Standards Work In Progress (continued) • Network Transport of RTCM via Internet Protocol (Ntrip)

Standards Work In Progress (continued) • Network Transport of RTCM via Internet Protocol (Ntrip) – Ntrip Version 2. 0, with Amendment 1 • Published on June 28, 2011 – Widely used in industry carrying not only RTCM data but numerous other data (even beyond proprietary GNSS receiver data) • Supporting TCP/IP, UDP, and SSL – Work In Progress • Sourcing the Station Log Files • Offering suggested source table meta-names to aid in more automation of stream selections.

RINEX Working Group • RINEX and SC-104 Tighter Relationship (~2 yrs ago) – RINEX

RINEX Working Group • RINEX and SC-104 Tighter Relationship (~2 yrs ago) – RINEX and RTCM essentially deal with same ‘observables’ – The independent committees now jointly develop solutions • Example: Phase alignment – Ensure RINEX can be created from RTCM 3. x – Joint decision to only further development of 3. x • Example: RINEX 3. 02 supports Bei. Dou; version 2. x does not. • BKG developing open source for RTCM 3 and RINEX converters – http: //software. rtcm-ntrip. org/ – teqc equivalent in the plans – RINEX 3. 03 current being considered • Several issues with 3. 02 raised by community that may require 3. 03 • Any version beyond 3. 02 will likely undergo RTCM-type interoperability testing

NMEA Working Group • NMEA and SC-104 Tighter Relationship – RTCM SC-104 Standards messages

NMEA Working Group • NMEA and SC-104 Tighter Relationship – RTCM SC-104 Standards messages traditionally from Reference Receiver / Network sent to User – Community requesting standardized messages for high precision work carrying end solutions reaching a wider range of other applications, systems and devices – Formed an NMEA Working Group (WG) within SC-104 • Will be developing messages that essentially carry solution results to other applications, systems and devices • Will likely be developing messages targeted at Network management side – Receiver Controls: e. g. , reset commands, elevation masks, etc. • These will be developed under NMEA-0183, 2000, and the new One. Net • WG Formed Sept 2013, thus no progress yet to report

Thank You • Thank You • RTCM SC-104 Participation • Questions

Thank You • Thank You • RTCM SC-104 Participation • Questions