SCIENTIFIC AND TECHNICAL AEROSPACE REPORTS

A Biweekly Publication of the National Aeronautics and Space Administration
VOLUME 44, ISSUE 13 - JULY 5, 2006

04 AIRCRAFT COMMUNICATIONS AND NAVIGATION
Includes all modes of communication with and between aircraft; air navigation systems (satellite and ground based); and air traffic control.

For related information see also 06 Avionics and Aircraft Instrumentation; 17 Space Communications, Spacecraft Communications, Command and Tracking; and 32 Communications and Radar.

20060016973 NAVSYS Corp., Colorado Springs, CO USA

Rapid Ambiguity Resolution Using Multipath Spatial Processing for High Accuracy Carrier Phase

A02, Hardcopy

Brown, Alison; Stolk, Kees; Jan 2006; 9 pp.; In English; Original contains color illustrations Report No.(s): AD-A444564; No Copyright; Avail.: CASI:

The largest error component on the carrier-phase observations is generally caused by carrier-phase multipath offsets. This generally results in a slow oscillating cyclic offset which must be averaged (either through satellite or vehicle motion) before reliable ambiguity resolution can be performed for kinematic positioning. NAVSYS has developed a digital spatial processing receiver that uses the spatial degrees of freedom within an antenna array to minimize multipath errors on the carrier-phase observations. This in turn makes the ambiguity solution more reliable and reduces the number of processing cycles needed to result in a kinematic position fix. In this paper, test results are presented showing the reduction in the carrier phase errors when using this approach. Kinematic positioning test results are also shown using the HAGR digital beamsteering GPS receiver. DTIC

Ambiguity; Antenna Arrays; Beam Steering; Global Positioning System; Multipath Transmission

20060018306 Aeronautical Systems Div., Wright-Patterson AFB, OH USA

Air-to-Ground Visual Simulation Demonstration. Volume 2

Oct 1976; 175 pp.; In English Contract(s)/Grant(s): Proj-2235 Report No.(s): AD-A444764; No Copyright; ONLINE: http://hdl.handle.net/100.2/ADA444764; Avail.: CASI: A08, Hardcopy

No abstract available

Simulation; Ground-Air-Ground Communication; Visual Observation

20060018320 Aeronautical Systems Div., Wright-Patterson AFB, OH USA

Air-to-Ground Visual Simulation Demonstration. Volume 1

Oct 1976; 205 pp.; In English Contract(s)/Grant(s): Proj-2235 Report No.(s): AD-A444763; No Copyright; ONLINE: http://hdl.handle.net/100.2/ADA444763; Avail.: CASI: A10, Hardcopy

No abstract available

Simulation; Ground-Air-Ground Communication; Visual Observation

20060019169 NASA Ames Research Center, Moffett Field, CA, USA

Discovering Atypical Flights in Sequences of Discrete Flight Parameters

Budalakoti, Suratna; Srivastava, Ashok N.; Akella, Ram; [2006]; 7 pp.; In English; 2006 IEEE Aerospace Conference, 4-11 Mar. 2006, Big Sky, MT, USA; Original contains black and white illustrations; No Copyright; Avail.: Other Sources This paper describes the results of a novel research and development effort conducted at the NASAAmes Research Center for discovering anomalies in discrete parameter sequences recorded from flight data. Many of the discrete parameters that are recorded during the flight of a commercial airliner correspond to binary switches inside the cockpit. The inputs to our system are records from thousands of flights for a given class of aircraft and destination. The system delivers a list of potentially anomalous flights as well as reasons why the flight was tagged as anomalous. This output can be analyzed by safety experts to determine whether or not the anomalies are indicative of a problem that could be addressed with a human factors intervention. The final goal of the system is to help safety experts discover significant human factors issues such as pilot mode confusion, i.e., a flight in which a pilot has lost situational awareness as reflected in atypicality of the sequence of switches that he or she throws during descent compared to a population of similar flights. We view this work as an extension of Integrated System Health Management (ISHM) where the goal is to understand and evaluate the combined health of a class of aircraft ar a given destination. Author

Flight Characteristics; Human Factors Engineering; Situational Awareness; Systems Integration; Anomalies; Safety; Sequencing

Source: NASA