Displaying present location in the site.


Michibiki-Satellite-based Augmentation System

Satellite Navigation brings forth Much Safer and More Efficient Aircraft Operation


  • Hitachiohta/Tokorozawa
    • Master Control Stations (2)
      • System Monitoring/Control
      • Satellite Error Calculation
      • Michibiki Orbit Determination
      • Ionospheric Delay Correction Calculation
      • Integrity Augmentation Processing

  • QZSS (Quasi-Zenith Satellite System) 
    • Ground Monitor Stations (13)
      • GPS/Michibiki (QZSS Satellite) Signal Reception/Collection

What is MSAS?

MSAS provides augmentation information, which improves the accuracy, reliability and safety of GPS, for aircraft using GPS navigation.
MSAS receives GPS signal at the Ground Monitor Stations and the Monitor & Ranging Stations, checks operational status of GPS, analyze GPS error and ionospheric delay, and then broadcasts augmentation information through Michibiki from the Master Control Stations.
NEC manufactured and delivered MSAS under contract with the Civil Aviation Bureau, Ministry of Land, Infrastructure, Transport and Tourism.

MSAS increases oceanic air traffic control capacity where there is no ground-based navigation system.

Merits of introducing MSAS

New CNS/ATM systems including MSAS not only improved coverage and accuracy increase air traf f ic control capacity but also produce the following merits.

  • Increased Safety
    • Direct flight path means less workload for both pilots and controllers resulting in more attention paid to the traffic situation.
    • Increased coverage results in increased use of instrument flight rules.
    • Flexible flight path makes weather deviation easy.

  • Protection of environment
    • Selection of the shortest flight path means fuel savings resulting in reduction of green house gas emissions.
    • Use of flexible flight path enables noise reduction in noise sensitive areas.

Flexible flight path can be chosen within the MSAS coverage bringing in shorter flight path leading to time and fuel savings.
Air Traffic Control
Airport operations