Department News
Integrated Global Positioning System (GPS)/Inertial Reference System (IRS)
Seminar Date
2000-06-15
Author
관리자
Date
2000-06-15
Views
878
1. 제목 : Integrated Global Positioning System (GPS)/Inertial Reference System (IRS)
- Potential Benefits and Current State of Technology
2. 연사 : Dr. Young Chang Lee (MITRE/CAASD, Virginia)
3. 일시 : 1999년 12월 1일 (수요일) 15:00
4. 장소 : 301동 1409-1호
5. 내용 :
Since the early 1990s, the Federal Aviation Administration (FAA) has been applying a great deal of funding and effort to transition from the current ground-based navigation and landing system to satellite-based navigation using the Global Positioning System (GPS) and its augmentations in the National Airspace System (NAS). Recently, however, there are growing concerns regarding the robustness of the satellite-based navigation system. Of particular concern is that GPS and its augmentation (e.g., Wide Area Augmentation System (WAAS) and Local Area Augmentation System (LAAS)) signals are vulnerable to intentional and unintentional interference such that safety may be compromised. Augmenting GPS with an inertial system can be a very effective risk mitigation method.
Inertial systems have been used for decades by commercial airliners. In particular, they have been used as a sole means of navigation in transoceanic flights. An inertial system has almost no high frequency noise, but it can have large low frequency errors (bias errors) that grow with time. GPS, on the other hand, has high frequency noise but good long-term accuracy (i.e., small bias errors). A GPS/inertial system properly integrated exploiting their complementary characteristics could improve the navigation performance significantly. In particular, it could improve continuity of service by coasting through periods of complete loss of GPS signals caused by intentional and unintentional GPS interference or by ionospheric scintillation.
First, this paper reviews the current trends of inertial navigation technology. Second, it investigates potential benefits and roles that an integrated GPS/inertial system could play and the cost and equipage issues. Finally, it analyzes coasting capability, that is, the capability to continue navigation while maintaining desired accuracy, upon loss of GPS signals caused by interference. Specifically, it derives analytically the amount of time that the system can coast upon complete loss of GPS signals as a function of inertial sensor accuracy and the type of aircraft turning maneuver after loss of GPS signals. This coasting capability is one of the major benefits of a GPS/inertial system because continuing navigation upon occurrence of an otherwise hazardous situation greatly improves safety of flight.
6. 연사 약력 :
1965-1969 B.S. in Electrical Engineering at Seoul National
University, Seoul, Korea
1971-1977 Ph.D. in Electrical Engineering (Control Systems)
at the University of Virginia, Charlottesville,
Virginia
1977-1980 Bendix Corporation, Test Systems Division,
Teterboro, New Jersey,
Senior Systems Analyst
1980-present Lead Engineer at MITRE/CAASD
7. 연락처 : 기계항공공학부 기창돈 교수 (전화 : 880-1912)
- Potential Benefits and Current State of Technology
2. 연사 : Dr. Young Chang Lee (MITRE/CAASD, Virginia)
3. 일시 : 1999년 12월 1일 (수요일) 15:00
4. 장소 : 301동 1409-1호
5. 내용 :
Since the early 1990s, the Federal Aviation Administration (FAA) has been applying a great deal of funding and effort to transition from the current ground-based navigation and landing system to satellite-based navigation using the Global Positioning System (GPS) and its augmentations in the National Airspace System (NAS). Recently, however, there are growing concerns regarding the robustness of the satellite-based navigation system. Of particular concern is that GPS and its augmentation (e.g., Wide Area Augmentation System (WAAS) and Local Area Augmentation System (LAAS)) signals are vulnerable to intentional and unintentional interference such that safety may be compromised. Augmenting GPS with an inertial system can be a very effective risk mitigation method.
Inertial systems have been used for decades by commercial airliners. In particular, they have been used as a sole means of navigation in transoceanic flights. An inertial system has almost no high frequency noise, but it can have large low frequency errors (bias errors) that grow with time. GPS, on the other hand, has high frequency noise but good long-term accuracy (i.e., small bias errors). A GPS/inertial system properly integrated exploiting their complementary characteristics could improve the navigation performance significantly. In particular, it could improve continuity of service by coasting through periods of complete loss of GPS signals caused by intentional and unintentional GPS interference or by ionospheric scintillation.
First, this paper reviews the current trends of inertial navigation technology. Second, it investigates potential benefits and roles that an integrated GPS/inertial system could play and the cost and equipage issues. Finally, it analyzes coasting capability, that is, the capability to continue navigation while maintaining desired accuracy, upon loss of GPS signals caused by interference. Specifically, it derives analytically the amount of time that the system can coast upon complete loss of GPS signals as a function of inertial sensor accuracy and the type of aircraft turning maneuver after loss of GPS signals. This coasting capability is one of the major benefits of a GPS/inertial system because continuing navigation upon occurrence of an otherwise hazardous situation greatly improves safety of flight.
6. 연사 약력 :
1965-1969 B.S. in Electrical Engineering at Seoul National
University, Seoul, Korea
1971-1977 Ph.D. in Electrical Engineering (Control Systems)
at the University of Virginia, Charlottesville,
Virginia
1977-1980 Bendix Corporation, Test Systems Division,
Teterboro, New Jersey,
Senior Systems Analyst
1980-present Lead Engineer at MITRE/CAASD
7. 연락처 : 기계항공공학부 기창돈 교수 (전화 : 880-1912)
