NASA Scientific and Technical Aerospace Reports

20060002321 SENSIS Corp., Dewitt, NY, USA
Range Enhancement to Wide Area Multilateration Processing
Beyer, Jeffrey; Proceedings of the Fifth Integrated Communications, Navigation, and Surveillance (ICNS) Conference and
Workshop; November 2005; 28 pp.; In English; See also 20060002231; Original contains color illustrations; No Copyright;
Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Traditional multilateration systems use a constellation of sensors to receive a single aircraft transmission and calculate a
very accurate position estimate using Time Difference of Arrival (TDOA) techniques. Geometric Dilution of Precision
(GDOP) is a measure of the target localization precision that can be obtained from a constellation of sensors using TDOA
processing. The GDOP associated with target localization within the boundary of a constellation of sensors is relatively small
and constant. As a target moves outside the constellation of sensors, the GDOP increases rapidly as the ratio of target range
to system baseline (distance between sensors) becomes large, rendering target localization impractical a relatively short
distance outside a sensor constellation. Recent research has yielded enhancements in multilateration processing techniques to
reduce the GDOP outside a constellation of sensors significantly improving the quality of surveillance. This paper
demonstrates how the enhancements in multilateration processing techniques which reduce the distribution of sensors required
to provide multilateration surveillance over a wide area. In addition, the positional accuracy of a developmental wide area
multilateration system with the enhancement is compared to the positional accuracy of traditional TDOA processing
techniques.
Author
Computerized Simulation; Systems Engineering; Data Processing; Tracking (Position)
20060002323 Microflight, Inc., USA
Airborne Internet Consortium Forum
Meer, James; Yost, Ralph; Proceedings of the Fifth Integrated Communications, Navigation, and Surveillance (ICNS)
Conference and Workshop; November 2005; 3 pp.; In English; See also 20060002231; Original contains color illustrations;
No Copyright; Avail.: CASI: A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
The goals and objectives of this workshop are: 1) Review the ICNS Conference and AI Session; 2) Gain feedback from
participants; and 3) Seek participant observations about the AI Consortium and Public/Private Partnership.
Derived from text
Internets; Organizations; Air Traffıc Control
20060002327 Federal Aviation Administration, Washington, DC, USA
Departure Exclusion Zone (DEZ) - a Future Concept to Enhance Runway Operations Using Aircraft Derived Data
Primeggia, Carmine; Hodgkins, Philip D.; Proceedings of the Fifth Integrated Communications, Navigation, and Surveillance
(ICNS) Conference and Workshop; November 2005; 29 pp.; In English; See also 20060002231; Original contains color
illustrations; No Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire
parent document
This paper highlights a concept for a Departure Exclusion Zone tool (DEZ). Wake turbulence accidents and incidents have
been, and continue to be, a significant contributor to the worldwide safety statistics. The National Transportation Safety Board
(NTSB) has raised concern over ‘the adequacy of air traffic control procedures’ and ‘pilot knowledge related to the avoidance
of wake vortices.’ The safety concern of wake vortices, particularly when lighter aircraft are following heavy aircrafts, has
caused the Federal Aviation Administration (FAA) to enact minimum separation requirements during the arrival and departure
phases of flight. The wake-turbulence separation criteria, while necessary, are currently a limiting factor in several airport
capacities. Current air traffic control procedures on vortex has focused on aircraft separations 2.5 miles at some facilities on
arrival to airports, but in many cases, the departure queues for certain runways are more severely limiting to airport capacity
than are arrival constraints. This paper examines the technical requirements for a system that relieves the departure constraints
enhancing the efficiency of runway operations. The proposed system uses the Flight Management System (FMS)/autopilot to
establish tracks that avoid the wake of the preceding aircraft. The Europeans are mandating Downlink of Aircraft Parameters
(DAP) of certain aircraft flight data parameters that make it possible to add the elements needed to calculate the wake
characteristics of any model aircraft. These additional parameters are called extended DAP ( eDAP). Given that an aircraft can
provide meteorological (wind, temperature and air density) and state data (model, speed, weight, etc), the wake vortices can
be calculated with sufficient accuracy to develop individual departure routes (tracks) for each aircraft to avoid the wake of the
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