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Controller-human interface design for the final approach spacing tool

June 17, 1995
  |
Conference Paper
Author:
Maria Picardi Kuffner
Published in:
Proc. IFAC Man-Machine Systems Conf., 27-29 June 1995, pp. 559-564.
Topic:
air traffic control
R&D area:
R&D group:

Summary

The Federal Aviation Administration is developing a set of software tools, known as the Center-TRACON Automation System (CTAS) to assist air traffic controllers in their management and control tasks. CTAS originated at National Aeronautics and Space Administration (NASA) Ames Research Center, where prototypes continue to evolve. In parallel, Massachusetts Institute of Technology/Lincoln Laboratory (MIT/LL) is refining and testing the software, including the Computer-Human Interface (CHI). This paper focuses on the CHI designed by MIT/LL for the Final Approach Spacing Tool (FAST) part of CTAS. The FAST design approach, CHI development and operational concept is presented.
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Summary

The Federal Aviation Administration is developing a set of software tools, known as the Center-TRACON Automation System (CTAS) to assist air traffic controllers in their management and control tasks. CTAS originated at National Aeronautics and Space Administration (NASA) Ames Research Center, where prototypes continue to evolve. In parallel, Massachusetts Institute...

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Controller-human interface design for the final approach spacing tool

Measuring fine structure in speech: application to speaker identification

May 9, 1995
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Conference Paper
Author:
Charles R. Jankowski Jr
…
Published in:
Proc. IEEE Int. Conf. on Acoustics, Speech and Signal Processing, ICASSP, Vol. 1, 9-12 May 1995, pp. 325-328.
Topic:
speaker recognition
R&D area:
R&D group:

Summary

The performance of systems for speaker identification (SID) can be quite good with clean speech, though much lower with degraded speech. Thus it is useful to search for new features for SID, particularly features that are robust over a degraded channel. This paper investigates features that are based on amplitude and frequency modulations of speech formants, high resolution measurement of fundamental frequency and location of "secondary pulses," measured using a high-resolution energy operator. When these features are added to traditional features using an existing SID system with a 168 speaker telephone speech database, SID performance improved by as much as 4% for male speakers and 8.2% for female speakers.
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Summary

The performance of systems for speaker identification (SID) can be quite good with clean speech, though much lower with degraded speech. Thus it is useful to search for new features for SID, particularly features that are robust over a degraded channel. This paper investigates features that are based on amplitude...

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Measuring fine structure in speech: application to speaker identification

Language identification using phoneme recognition and phonotactic language modeling

May 9, 1995
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Conference Paper
Author:
Marc A. Zissman
Published in:
Proc. IEEE Int. Conf. on Acoustics, Speech and Signal Processing, Vol. 5, ICASSP, 9-12 May 1995, pp. 3503-3506.
Topic:
language recognition
R&D area:
R&D group:

Summary

A language identification technique using multiple single-language phoneme recognizers followed by n-gram language models yielded to performance at the March 1994 NIST language identification evaluation. Since the NIST evaluation, work has been aimed at further improving performance by using the acoustic likelihoods emitted from gender-dependent phoneme recognizers to weight the phonotactic likelihoods output from gender-dependent language models. We have investigated the effect of restricting processing to the most highly discriminating n-grams, and we have also added explicit duration modeling at the phonotactic level. On the OGI Multi-language Telephone Speech Corpus, accuracy on an 11-language identification task has risen to 89% on 45-s utterances and 79% on 10-s utterances. Two-language classification accuracy is 98% and 95% for the 45-s and 10-s utterance, respectively. Finally, we have started to apply these same techniques to the problem of dialect identification.
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Summary

A language identification technique using multiple single-language phoneme recognizers followed by n-gram language models yielded to performance at the March 1994 NIST language identification evaluation. Since the NIST evaluation, work has been aimed at further improving performance by using the acoustic likelihoods emitted from gender-dependent phoneme recognizers to weight the...

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Language identification using phoneme recognition and phonotactic language modeling

The effects of telephone transmission degradations on speaker recognition performance

May 9, 1995
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Conference Paper
Author:
Douglas A. Reynolds
…
Published in:
Proc. IEEE Int. Conf. on Acoustics, Speech and Signal Processing, ICASSP, Vol. 1, Speech, 9-12 May 1995, pp. 329-332.
Topic:
speaker recognition
R&D area:
R&D group:

Summary

The two largest factors affecting automatic speaker identification performance are the size of the population an the degradations introduced by noisy communication, channels (e.g., telephone transmission). To examine experimentally these two factors, this paper presents text-independent speaker identification results for varying speaker population sizes up to 630 speakers for both clean, wideband speech and telephone speech. A system based on Gaussian mixture speaker identification and experiments are conducted on the TIMIT and NTIMIT databases. This is believed to be the first speaker identification experiments on the complete 630 speaker TIMIT and NTIMIT databases and the largest text-independent speaker identification task reported to date. Identification accuracies of 99.5% and 60.7% are achieved on the TIMIT and NTIMIT databases, respectively. This paper also presents experiments which examine and attempt to quantify the performance loss associated with various telephone degradations by systematically degrading the TIMIT speech in a manner consistent with measured NTIMIT degradations and measuring the performance loss at each step. It is found that the standard degradations of filtering and additive noise do not account for all of the performance gap between the TIMIT and NTIMIT data. Measurements of nonlinear microphone distortions are also...
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Summary

The two largest factors affecting automatic speaker identification performance are the size of the population an the degradations introduced by noisy communication, channels (e.g., telephone transmission). To examine experimentally these two factors, this paper presents text-independent speaker identification results for varying speaker population sizes up to 630 speakers for both...

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The effects of telephone transmission degradations on speaker recognition performance

Data processing techniques for airport surveillance radar weather sensing

May 8, 1995
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Conference Paper
Author:
Mark E. Weber
…
Published in:
Proc. IEEE 1995 Int. Radar Conf., 8-11 May 1995, pp. 521-528.
Topic:
aviation weather
R&D area:
R&D group:

Summary

Discusses data processing techniques that can provide high quality, automated weather information using the FAA's existing Airport Surveillance Radars (ASR-9). The cost of modifying the ASR-9 is significantly less than that for deployment of the dedicated terminal Doppler weather radar. These techniques have been implemented on a prototype ASR-9 weather surveillance processor (WSP) and have been tested operationally at the Orlando, FL and Albuquerque, NM air traffic control towers. The key to the success of this system has been the development of innovative data processing techniques that accommodate the non-optimum parameters of the ASR as a weather sensor. The authors motivate the development of the ASR-9 WSP system and describe in detail the data processing techniques that have been employed to achieve an operationally useful capability. They provide an overview of the WSP and the ongoing system development and test program. They provide specifics on the data processing algorithms that have been key to successful implementation of this capability.
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Summary

Discusses data processing techniques that can provide high quality, automated weather information using the FAA's existing Airport Surveillance Radars (ASR-9). The cost of modifying the ASR-9 is significantly less than that for deployment of the dedicated terminal Doppler weather radar. These techniques have been implemented on a prototype ASR-9 weather...

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Data processing techniques for airport surveillance radar weather sensing

Comparative analysis of ground-based wind shear detection radars

May 8, 1995
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Conference Paper
Author:
Mark E. Weber
…
Published in:
Proc. IEEE 1995 Int. Radar Conf., 8-11 May 1995, pp. 486-495.
Topic:
wind shear
R&D area:
R&D group:

Summary

The UNISYS Corporation has developed a microburst prediction radar (MBPR) to provide detection and short-term predictions of the most hazardous form of low altitude wind shear in the vicinity of an airport. The MBPR is intended for deployment on- or near-airport so as to minimize range coverage (and associated radar power-aperture) requirements. Like the airport surveillance radar wind shear processor (ASR-WSP), the cost of the MBPR is significantly less than that of the terminal Doppler weather radar (TDWR) so that its deployment at smaller airports might be economically justified if the performance is operationally acceptable. Field tests of engineering prototypes of the MBPR have been conducted in conjunction with FAA-sponsored TDWR and WSP demonstration programs. We assess the capabilities and limitations of each of these systems using a consistent methodology that emphasizes the comparative analysis of the significant parameters of each radar in relation to wind shear phenomenology. An extensive database on wind shear event radar cross section, spatial structure and intensity distribution-derived through our FAA-sponsored testing of TDWR and ASR-WSP prototypes is an important asset in developing this comparison.
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Summary

The UNISYS Corporation has developed a microburst prediction radar (MBPR) to provide detection and short-term predictions of the most hazardous form of low altitude wind shear in the vicinity of an airport. The MBPR is intended for deployment on- or near-airport so as to minimize range coverage (and associated radar...

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Comparative analysis of ground-based wind shear detection radars

Terminal Weather Information for Pilots (TWIP) Test Report for 1994 Memphis and Orlando Demonstrations

April 28, 1995
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Project Report
Author:
Steven D. Campbell
Published in:
MIT Lincoln Laboratory Report ATC-227
Topic:
weather
R&D area:
R&D group:

Summary

Demonstrations of delivering the Terminal Weather Information for Pilots (TWIP) products to air carrier pilots via the Aircraft Communications Addressing and Reporting System (ACARS) data link were carried out at Memphis and Orlando during the summer of 1994. Six airlines participated in the demonstrations at both airports. The Terminal Weather Text Message and the Terminal Weather Character Graphics Depiction were evaluated using request/reply and forced update approaches. In the first case, the pilot needed to make a request in order to obtain the TWIP products. In the second case, the TWIP message was sent to the aircraft automatically when certain criteria were met (e.g., the aircraft was within 20 minutes of landing and wind shear alerts began at the airport). Five of the airlines used the request/reply approach, and one airline used the forced update approach. Pilot and contoller response to the TWIP products were evaluated using questionnaires. Statistics on message traffic and content were analyzed, and some cases were analyzed in detail to compare the TWIP products with the existing Surface Aviation Observation (SAO) reports. Recorded radio traffic also was analyzed to determine if there was any effect on the number of requests for terminal weather information. Pilots rated the TWIP products favorably, with most indicating that the messages provided improved situational awareness of terminal weather hazards without substantially increased cockpit workload. Controller reaction to the TWIP demonstration was generally neutral, indicating that providing these messages to pilots caused no substantial increase in contoller workload. Further results of the demonstration are discussed in the report, along with recommendations for subsequent TWIP demonstrations.
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Summary

Demonstrations of delivering the Terminal Weather Information for Pilots (TWIP) products to air carrier pilots via the Aircraft Communications Addressing and Reporting System (ACARS) data link were carried out at Memphis and Orlando during the summer of 1994. Six airlines participated in the demonstrations at both airports. The Terminal Weather...

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Terminal Weather Information for Pilots (TWIP) Test Report for 1994 Memphis and Orlando Demonstrations

Automatic dependent surveillance broadcast via GPS-squitter: a major upgrade to the National Airspace System

April 18, 1995
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Conference Paper
Author:
Ronnie D. Jones
…
Published in:
SPIE, Vol. 2464, Air Traffic Control Technologies, 18-19 April 1995, pp. 2-13.
Topic:
surveillance
R&D area:
R&D group:

Summary

GPS-Squitter is a technology for Surveillance of aircraft via broadcast of their GPS-determined positions to all listeners, using the Mode S data link. It can be used to provide traffic displays, on the ground for controllers and in the cockpit for pilots, and will enhance TCAS performance. It is compatible with the existing ground-based beacon interrogator radar system and is an evolutionary way to move from ground-based-radar surveillance to satellite-based surveillance. GPS-Squitter takes advantage of the substantial investment made by the U.S. in the powerful GPS position-determining system and has the potential to free the Federal Aviation Administration from having to continue maintaining a precise position-determining capability in ground-based radar. This would permit phasing out the ground-based secondary surveillance radar system over a period of 10 to 20 years and replacing it with much simpler ground stations, resulting in cost savings of hundreds of millions of dollars.
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Summary

GPS-Squitter is a technology for Surveillance of aircraft via broadcast of their GPS-determined positions to all listeners, using the Mode S data link. It can be used to provide traffic displays, on the ground for controllers and in the cockpit for pilots, and will enhance TCAS performance. It is compatible...

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Automatic dependent surveillance broadcast via GPS-squitter: a major upgrade to the National Airspace System

Initial evaluation of the Oregon State University Planetary Boundary Layer Column Model for ITWS applications

April 13, 1995
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Project Report
Author:
John L. Keller
…
Published in:
MIT Lincoln Laboratory Report ATC-233
Topic:
weather
R&D area:
R&D group:

Summary

The Federal Aviation Administration (FAA) Integrated Terminal Weather System (ITWS) is supporting the development of products important for air traffic control in the terminal area. Some ITWS is supporting the development of products important for air traffic control in the terminal area. Some ITWS products will allow air traffic managers to anticipate operationally significant short-term (0-30 min) changes in ceiling and visibility (C&V) and aircraft separations necessary to avoid encounters with wake vortices. Development of such products exploits data that will be available from new FAA terminal area sensor systems. These sensor systems include Terminal Doppler Weather Radar (TDWR), Next Generation Weather Radar (NEXRAD), the Meteorological Data Collection and Reporting System (MDCRS), and the Automated Surface Observing System (ASOS). A Dynamic Atmospheric Vertical Structure Nowcast System (DAVS-NS) is being developed that will add value to ITWS by providing current analyses and short-term forecasts of the vertical atmospheric structure focused at specific sites within the terminal domain. This report summarizes the initial evaluation of the Oregon State University one-dimensional boundary layer model for its potential role within a DAVS-NS.
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Summary

The Federal Aviation Administration (FAA) Integrated Terminal Weather System (ITWS) is supporting the development of products important for air traffic control in the terminal area. Some ITWS is supporting the development of products important for air traffic control in the terminal area. Some ITWS products will allow air traffic managers...

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Initial evaluation of the Oregon State University Planetary Boundary Layer Column Model for ITWS applications

TCAS III bearing error evaluation

April 13, 1995
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Project Report
Author:
Douglas W. Burgess
…
Published in:
MIT Lincoln Laboratory Report ATC-231
Topic:
surveillance
R&D area:
R&D group:

Summary

TCAS III seeks to enhance TCAS II by providing resolution advisory (RA) capability in the horizontal plane. Additionally, elimination of nuisance RAs through the use of miss distance filtering (MDF) are sought to make TCAS more compatible within the airspace. Both functions (horizontal RAs and MDF) are enabled with accurate estimates of the horizontal miss distance. TCAS III estimates of miss distance rely on range and bearing measurements derived from intruder aircraft replies. Large errors in the TCAS bearing measurement can be introduced by the airframe structure and other antennas in the vicinity of the TCAS antenna. These large bearing errors can result in large miss distance estimation errors, which will directly affect the performance of the horizontal RA and MDF operation. In evaluating the performance of the bearing measurements, measurements of the bearing error were used in a simulation of TCAS III surveillance and collision avoidance functions to assess their effect on performance. The performance was evaluated by examining (1) the expected percentage of horizontal RAs issued, (2) the expected reduction in nuisance RAs by the MDF, and (3) the reliability of the monitoring process during a horizontal RA maneuver.
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Summary

TCAS III seeks to enhance TCAS II by providing resolution advisory (RA) capability in the horizontal plane. Additionally, elimination of nuisance RAs through the use of miss distance filtering (MDF) are sought to make TCAS more compatible within the airspace. Both functions (horizontal RAs and MDF) are enabled with accurate...

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TCAS III bearing error evaluation
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