MSAS (multifunctional satellite augmentation system)
The Multifunctional Satellite Augmentation System (MSAS) is a regional satellite-based augmentation system (SBAS) developed by the Japanese government to augment the existing Global Navigation Satellite Systems (GNSS) such as the Global Positioning System (GPS) and the Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS) in the Asia-Oceania region. MSAS provides high-precision positioning, navigation, and timing (PNT) services for aviation, maritime, and land-based applications.
MSAS uses a network of ground-based reference stations to measure and monitor the errors and biases in the GNSS signals caused by atmospheric and other environmental effects. The reference station data is then transmitted to a master control center (MCC) where it is processed to generate correction data, which is then broadcasted to users via a geostationary satellite.
MSAS works by transmitting correction signals that enable GNSS receivers to compensate for atmospheric and other environmental effects that can cause errors in positioning and timing measurements. The correction signals are transmitted via a dedicated MSAS signal on L-band frequency and are received by MSAS-capable GNSS receivers.
MSAS provides four types of services, namely:
- Precision Approach Service (PAS) – provides enhanced accuracy and integrity for approach and landing operations in aviation, enabling pilots to make precision approaches to airports in low-visibility conditions.
- Non-Precision Approach Service (NPAS) – provides basic accuracy and integrity for approach and landing operations in aviation, enabling pilots to make non-precision approaches to airports.
- Marine Service (MS) – provides enhanced accuracy and integrity for maritime navigation and positioning, enabling ships to navigate through narrow channels and congested waterways.
- Land Service (LS) – provides enhanced accuracy and integrity for land-based applications such as surveying, mapping, and geodesy, enabling precise measurements and positioning.
MSAS was developed by the Japanese government in collaboration with the private sector and was officially launched in 2007. The system is operated by the Japan Civil Aviation Bureau (JCAB) and the Japan Coast Guard (JCG). MSAS was designed to support various applications such as aviation, maritime, and land-based activities, including disaster management, search and rescue, and environmental monitoring.
MSAS covers the Asia-Oceania region and has a service area that extends from the Indian Ocean to the western Pacific Ocean, including Japan, South Korea, Taiwan, and parts of Southeast Asia. MSAS provides coverage to more than 200 airports in the region, including 56 airports in Japan. MSAS is interoperable with other SBAS systems such as the Wide Area Augmentation System (WAAS) in the United States and the European Geostationary Navigation Overlay Service (EGNOS) in Europe, enabling seamless navigation and positioning services for users operating across different regions.
MSAS uses advanced technologies such as real-time kinematic (RTK) positioning, which provides centimeter-level accuracy for land-based applications. MSAS also incorporates a safety net feature that provides an alert to users in the event of a system failure or anomaly. The safety net feature ensures that users are aware of any potential issues and can take appropriate action to maintain safety and reliability.
MSAS has been successfully implemented in various applications, including aviation, maritime, and land-based activities. In aviation, MSAS has been used to support precision approaches to airports in low-visibility conditions, improving safety and reliability for air traffic operations. In maritime, MSAS has been used to enable ships to navigate through narrow channels and congested waterways, improving safety and efficiency for maritime operations. In land-based applications, MSAS has been used to support surveying, mapping, and geodesy activities, enabling precise measurements and positioning for various engineering and construction projects.
MSAS has also been used in disaster management and search and rescue operations, providing accurate and reliable positioning information to emergency responders and aid workers during natural disasters and other emergencies. For example, MSAS was used during the 2011 Tohoku earthquake and tsunami in Japan to support search and rescue operations and provide vital positioning information to emergency responders.
MSAS is a robust and reliable system that has undergone extensive testing and evaluation to ensure its safety and reliability. The system is subject to stringent performance requirements and is continuously monitored and maintained to ensure that it meets these requirements. MSAS has also been certified by various aviation authorities, including the Federal Aviation Administration (FAA) in the United States and the Civil Aviation Administration of China (CAAC), further demonstrating its safety and reliability.
In addition to MSAS, there are other regional SBAS systems operating in different parts of the world, such as the Indian GPS Aided Geo Augmented Navigation (GAGAN) system, the Russian System for Differential Corrections and Monitoring (SDCM), and the South Korean GPS-Aided GEO Augmented Navigation (KASS) system. These systems provide similar services to MSAS and are designed to augment the existing GNSS systems in their respective regions.
In conclusion, the Multifunctional Satellite Augmentation System (MSAS) is a regional satellite-based augmentation system (SBAS) developed by the Japanese government to augment the existing Global Navigation Satellite Systems (GNSS) in the Asia-Oceania region. MSAS provides high-precision positioning, navigation, and timing (PNT) services for aviation, maritime, and land-based applications, including disaster management, search and rescue, and environmental monitoring. MSAS has been successfully implemented in various applications and is a robust and reliable system that has undergone extensive testing and evaluation to ensure its safety and reliability.