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The Multi-functional Satellite Augmentation System (MSAS) is the Japanese [[SBAS General Introduction|SBAS]] System: a GPS Augmentation system with the goal of improving its accuracy, integrity, and availability, and that uses the Multifunctional Transport Satellites (MTSAT)  owned and operated by the [http://www.mlit.go.jp Japanese Ministry of Land, Infrastructure and Transport] and the [http://www.jma.go.jp Japan Meteorological Agency (JMA)]. MSAS for aviation use was declared operational on September 27, 2007.<ref>[http://en.wikipedia.org/wiki/Multi-functional_Satellite_Augmentation_System MSAS in Wikipedia]</ref>
The MTSAT Satellite Augmentation System ([[Work in Progress:MSAS General Introduction|MSAS]]) is the Japanese [[SBAS General Introduction|Satellite Based Augmentation System (SBAS)]] System:<ref name="MSAS_STATUS_2007">[http://www.oosa.unvienna.org/pdf/icg/2007/icg2/presentations/04_01.pdf MSAS Current Status, Japan Civil Aviation Bureau,] [http://www.oosa.unvienna.org/oosa/SAP/gnss/icg/icg02/presentations.html Second Meeting of the International Committee on Global Navigation Satellite Systems (ICG) organized by the International Space Research Organization,  Bangalore, India , 5 - 7 September 2007]</ref> a GPS Augmentation system with the goal of improving its accuracy, integrity, and availability, and that uses the Multifunctional Transport Satellites (MTSAT)  owned and operated by the [http://www.mlit.go.jp Japanese Ministry of Land, Infrastructure and Transport] and the [http://www.jma.go.jp Japan Meteorological Agency (JMA).]
First tests were accomplished successfully, and MSAS system for aviation use was declared operational in September 27, 2007,<ref name="MSAS_STATUS_2007_2">[http://www.navcen.uscg.gov/pdf/cgsicMeetings/47/%5B24%5Dqzzmsas.pdf QZSS / MSAS Status,] CGSIC –47th Meeting ,Fort Worth, Texas September25, 2007, Satoshi KOGURE, [http://www.jaxa.jp/index_e.html Japan Aerospace Exploration Agency,] QZSS Project Team</ref><ref name="MSAS_GPSW">[http://www.gpsworld.com/survey/perspectives-late-april-2008-7289 Eric Gakstatter, Perspectives - Late April 2008, GPSworld, April 15, 2008]</ref> providing a service of horizontal guidance for En-route through Non-Precision Approach.<ref name="MSAS_STATUS_2007"/><ref name="MSAS_STATUS_2007_2"/><ref name="MSAS_STATUS_2008">[http://www.oosa.unvienna.org/pdf/icg/2008/icg3/08-1.pdf Overview of MSAS, Presentation for ICG-3, 2008]</ref>


GPS signals are received at the MSAS Ground Monitor Stations (GMS) and MSAS Monitor & Ranging Stations. These stations check operational status of GPS, and transmit GPS data to Master Control Stations that analyze GPS error and ionospheric delay. Then, these Master stations compute Augmentation information and broadcast it to GEO MTSAT (Multi-functional Transport Satellite)<ref>[http://en.wikipedia.org/wiki/Multi-Functional_Transport_Satellite MTSAT in Wikipedia]</ref> satellites. Those satellites, MTSAT, rebroadcast the correction messages back to Earth, where MSAS-enabled GPS receivers use the MSAS corrections to compute a reliable and accurate position.


==MSAS Signal Structure==
==MSAS Signal Structure==


[[SBAS Fundamentals|Signal characteristics]] are compliant with ICAO SARPs:<ref name="ICAO_SARPS">[http://www.icao.org ICAO] Standards and Recommended Practices, Annex 10, Volume 1 Radio Navigation Aids, July 2006</ref>
[[SBAS Fundamentals|Signal characteristics]] are compliant with ICAO SARPs:<ref name="MSAS_STATUS_2008"/><ref name="ICAO_SARPS">[http://www.icao.org ICAO] Standards and Recommended Practices, Annex 10, Volume 1 Radio Navigation Aids, July 2006</ref>
*Frequency ; L1 = 1575.42MHz.
*Bandwidth ; L1 ±2.2 MHz band.
*Data Rate; 500 symbols per Second, 1/2 convolutional encoded with a Forward Error Correction (FEC) code (250 effective bits per second).
*Signal strength on the earth surface >-161dBw at 5 degrees elevation.


Frequency ; L1 = 1575.42MHz.
The future lines of improvement of MSAS signals are:<ref name="MSAS_STATUS_2008"/>
*Band width expansion for L1.
*L5 signal (preparation for Dual-Frequency operations).
*Compatibility & Interoperability achivement between the different SBAS and GNSS constellations.


– Bandwidth ; L1 ±2.2 MHz band.
For an introduction on the signal structure, please refer to the article [[The EGNOS SBAS Message Format Explained]].
 
– Data Rate; 500 symbols per Second, 1/2 convolutional encoded with a Forward Error Correction (FEC) code (250 effective bits per second).
 
– Signal strength on the earth surface >-161dBw at 5 degrees elevation.
 
• The future lines of improvement of MSAS signals are:<ref>[http://www.oosa.unvienna.org/pdf/icg/2008/icg3/08-1.pdf Overview of MSAS, Presentation for ICG-3, 2008]</ref>
 
– Band width expansion for L1.
 
– L5 signal (preparation for Dual-Frequency operations).
 
– Compatibility & Interoperability achivement between the different SBAS and GNSS constellations.


==Notes==
==Notes==

Revision as of 07:34, 2 August 2011


MSASMSAS
Title MSAS Signal Structure
Author(s) GMV.
Level Basic
Year of Publication 2011
Logo GMV.png


The MTSAT Satellite Augmentation System (MSAS) is the Japanese Satellite Based Augmentation System (SBAS) System:[1] a GPS Augmentation system with the goal of improving its accuracy, integrity, and availability, and that uses the Multifunctional Transport Satellites (MTSAT) owned and operated by the Japanese Ministry of Land, Infrastructure and Transport and the Japan Meteorological Agency (JMA).

First tests were accomplished successfully, and MSAS system for aviation use was declared operational in September 27, 2007,[2][3] providing a service of horizontal guidance for En-route through Non-Precision Approach.[1][2][4]


MSAS Signal Structure

Signal characteristics are compliant with ICAO SARPs:[4][5]

  • Frequency ; L1 = 1575.42MHz.
  • Bandwidth ; L1 ±2.2 MHz band.
  • Data Rate; 500 symbols per Second, 1/2 convolutional encoded with a Forward Error Correction (FEC) code (250 effective bits per second).
  • Signal strength on the earth surface >-161dBw at 5 degrees elevation.

The future lines of improvement of MSAS signals are:[4]

  • Band width expansion for L1.
  • L5 signal (preparation for Dual-Frequency operations).
  • Compatibility & Interoperability achivement between the different SBAS and GNSS constellations.

For an introduction on the signal structure, please refer to the article The EGNOS SBAS Message Format Explained.

Notes

References