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Generation of the DABS network coverage map

March 20, 1980
  |
Project Report
Author:
David Reiner
Published in:
MIT Lincoln Laboratory Report ATC-98
Topic:
surveillance
R&D area:
R&D group:

Summary

This paper describes the technique of designing the network management coverage map files necessary to coordinate a network of DABS sensors. First, the concept of the DABS network is defined, and the functions of Network Management are briefly described, as they relate to the coverage map. Then, the rationale for the coverage map is given together with definitions of the map structure and the information required in the file. Implementation of these definitions is illustrated in terms of a specific example: a network of four DABS sensors in the Washington, D.C. area. As configured, each of the sensors provides service to only one of four ATC facilities (three TRACONs and one ARTCC). The resulting map generation process illustrates not only the general principles but also the significant effects of ATC control area geometry and ATARs requirements. Finally, the procedure required for automated map generation is defined. This procedure assumes the use of an interactive computer display terminal and is applicable to any sensor network and ATC facility configuration.
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Summary

This paper describes the technique of designing the network management coverage map files necessary to coordinate a network of DABS sensors. First, the concept of the DABS network is defined, and the functions of Network Management are briefly described, as they relate to the coverage map. Then, the rationale for...

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Generation of the DABS network coverage map

Zoom antenna

February 12, 1980
  |
Project Report
Author:
Jean-Claude Sureau
Published in:
Project Report ATC-90, MIT Lincoln Laboratory
Topic:
radar
R&D area:
R&D group:

Summary

In current ATC radars, high altitude targets are at a disadvantage when competing with low altitude undesired returns such as ground clutter and birds. The "zoom antenna" technique is proposed as a means of virtually eliminating this problem. An implementation based on control of multiple elevation beams during each range sweep interval is recommended as applicable to both S-band and L-band ATC radars.
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Summary

In current ATC radars, high altitude targets are at a disadvantage when competing with low altitude undesired returns such as ground clutter and birds. The "zoom antenna" technique is proposed as a means of virtually eliminating this problem. An implementation based on control of multiple elevation beams during each range...

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Zoom antenna

MLS Multipath Studies, Phase 3, Volume II: Development and Validation of Model for MLS Techniques

February 7, 1980
  |
Project Report
Author:
Samuel J. Dolinar Jr
…
Published in:
MIT Lincoln Laboratory Report ATC-88,II
Topic:
air traffic control
R&D area:
R&D group:

Summary

This report presents work done during phase 3 of the US national Microwave Landing System (MLS) program toward developing a computer simulation model of the MLS multipath effects, the experimental validation ot the model, and the application of the model to investigate multipath performance of ICAO proposals for the new approach and landing guidance system. This second volume of the report presents the mathematical models and validation data for the MLS techniques which were assessed in detail by the All Weather Operations Panel of the Interational Civil Aviation Organization. The specific techniques modeled are: 1. The Time Reference Scanning Beam (TRSB) system proposed by the United States (US) and Australia, with prime emphasis on the US equipment implementation and field test data, 2. the Doppler scan (DMLS) proposed by the United Kingdom, and 3. the DME Based Landing System (DLS) proposed by the Federal Republic of Germany.
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Summary

This report presents work done during phase 3 of the US national Microwave Landing System (MLS) program toward developing a computer simulation model of the MLS multipath effects, the experimental validation ot the model, and the application of the model to investigate multipath performance of ICAO proposals for the new...

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MLS Multipath Studies, Phase 3, Volume II: Development and Validation of Model for MLS Techniques

DABS installation and siting criteria

January 29, 1980
  |
Project Report
Author:
Ronald G. Sandholm
Published in:
MIT Lincoln Laboratory Report ATC-99
Topic:
surveillance
R&D area:
R&D group:

Summary

This paper provides information on site-associated phenomena that affect the proper operation of a DABS sensor and therefore warrant serious consideration when siting a radar. The DABS-related discussion is intended to be a supplement to the ATCRBS siting criteria presented in the FAA Primary/Secondary Terminal Radar Siting Handbook. The paper discusses siting criteria as they relate to the DABS sensor antenna system, as opposed to the ATCRBS hogtrough antenna, and importantly, addresses those characteristics of the surrounding environment that are crucial to proper DABS/ATARS surveillance.
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Summary

This paper provides information on site-associated phenomena that affect the proper operation of a DABS sensor and therefore warrant serious consideration when siting a radar. The DABS-related discussion is intended to be a supplement to the ATCRBS siting criteria presented in the FAA Primary/Secondary Terminal Radar Siting Handbook. The paper...

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DABS installation and siting criteria

Evaluation of the MTD in a high-clutter environment

January 1, 1980
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Conference Paper
Author:
John R. Anderson
…
Published in:
IEEE 1980 Int. Radar Conf., 28-30 April 1980, Arlington, VA, pp. 219-224.
Topic:
radar
R&D area:
R&D group:

Summary

The MTD (Moving Target Detector) is an automated radar signal and data processing system designed to improve the performance of air surveillance radars in various forms of clutter while providing a low output false alarm rate. This paper briefly describes the architecture of the MTD processor and presents the results of a field evaluation of the system using the ASR-7 terminal radar at Burlington, Vermont.
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Summary

The MTD (Moving Target Detector) is an automated radar signal and data processing system designed to improve the performance of air surveillance radars in various forms of clutter while providing a low output false alarm rate. This paper briefly describes the architecture of the MTD processor and presents the results...

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Evaluation of the MTD in a high-clutter environment

Effects of common band (3500-3700 MHz) operation of geostationary satellites and the FAA limited-surveillance radar

November 9, 1979
  |
Project Report
Author:
David Karp
…
Published in:
MIT Lincoln Laboratory Report ATC-92
Topic:
surveillance
R&D area:
R&D group:

Summary

The study reported investigates the likelihood of interference by FDM/FM transmissions from geostationary satellites operating in the frequency range 3500-3700 MHz upon proposed FAA limited-surveillance radars operating in the same band. It is concluded, based upon the analysis, that the FAA limited-surveillance radars and the geostationary satellites can function in a common band, 3500-3700 MHz with only slight degradation to the radar coverage.
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Summary

The study reported investigates the likelihood of interference by FDM/FM transmissions from geostationary satellites operating in the frequency range 3500-3700 MHz upon proposed FAA limited-surveillance radars operating in the same band. It is concluded, based upon the analysis, that the FAA limited-surveillance radars and the geostationary satellites can function in...

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Effects of common band (3500-3700 MHz) operation of geostationary satellites and the FAA limited-surveillance radar

Discrete address beacon system data link

November 8, 1979
  |
Conference Paper
Author:
John L. Leeper
…
Published in:
3rd Digital Avionics Sys. Conf., 6-7 Nov. 1979, pp. 117-121.
Topic:
air traffic control
R&D area:
R&D group:

Summary

The Discrete Address Beacon System (DABS) is a surveillance and communication system for air traffic control. DABS is under development as an evolutionary replacement for the FAA's existing Air Traffic Control Radar Beacon System (ATCRBS) to enhance surveillance and provide a digital data communication capability. Each DABS aircraft recognizes and responds with a unique code (its discrete address), thus permitting data link messages to and from a particular aircraft to be accommodated integrally with the surveillance interrogations and replies. The FAA i s currently testing a set of data link applications which will provide aviation services for the initial field implementation of DABS. Link formats, ground interfaces, and systems to support a set of data link applications are also being evaluated for inclusion in the DABS field implementation. The initial data link services include ATC coordination messages and ground-to-air dissemination of weather and aviation related information. Uplink ATC messages include Minimum Safe Altitude Warning (MSAW) Alerts, Altitude Assignment Clearance Confirmation messages, and Takeoff Clearance Confirmation messages. These messages provide the pilot with a supplementary visual confirmation of voice communications. The services also include the capability for the pilot to request weather products derived from National Weather Service (NUS) information. The weather products include surface observations, terminal forecasts, winds aloft, pilot reports, hazardous weather advisories and digitized weather radar Information. Real-time surface measurements from the Enhanced Terminal Information Service (ETIS) are also included. The ETIS i s a flight advisory service which provides the pilot information to assist in conducting safe approaches to (or departures from) an airport. It includes information normally provided by the current Automated Terminal Information Service (ATIS) plus additional data such as weather alerts which pertain to the airport of interest. A DABS data link avionics system has been developed for the purpose of demonstrating and evaluating the initial services. It consists of an airborne microprocessor system with a variety of peripherals and interfaces. The microprocessor communicates with the ground-based equipment via a DABS transponder. Data link information included in the uplink interrogations is processed in the airborne microprocessor and then displayed to the pilot. The display device is a time-shared weather radar indicator with a 256 x 256 bit color graphics capability. Other peripherals include a printer, pilot keyboard, altitude alerter, and a multifunction annunciator capable of speech output.
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Summary

The Discrete Address Beacon System (DABS) is a surveillance and communication system for air traffic control. DABS is under development as an evolutionary replacement for the FAA's existing Air Traffic Control Radar Beacon System (ATCRBS) to enhance surveillance and provide a digital data communication capability. Each DABS aircraft recognizes and...

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Discrete address beacon system data link

The tradeoff between delay and TASI advantage in a packetized speech multiplexer

November 1, 1979
  |
Journal Article
Author:
Clifford J. Weinstein
…
Published in:
IEEE Trans. on Commun., Vol. COM-27, No. 11, November 1979, pp. 1716-20.
Topic:
signal processing
R&D area:
R&D group:

Summary

A packetized speech multiplexer differs from a circuit-switched TASI system in that the presence of a packet buffer allows a tradeoff where the TASI advantage can be increased at a cost in packet delay. This tradeoff is investigated via a simulation. Results are presented to show the relations between TASI advantage and delay, for both an average delay criterion and a maximum delay criterion. It is shown that, particularly for the case where small numbers of talkers are multiplexed, the packetized system offers significant improvements in TASI advantage over the conventional circuit-switched multiplexer, at modest costs in packet delay.
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Summary

A packetized speech multiplexer differs from a circuit-switched TASI system in that the presence of a packet buffer allows a tradeoff where the TASI advantage can be increased at a cost in packet delay. This tradeoff is investigated via a simulation. Results are presented to show the relations between TASI...

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The tradeoff between delay and TASI advantage in a packetized speech multiplexer

Air traffic density and distribution measurements

May 3, 1979
  |
Project Report
Author:
William H. Harman III
Published in:
MIT Lincoln Laboratory Report ATC-80
Topic:
air traffic control
R&D area:
R&D group:

Summary

Results of measurements to determine peak air traffic densities, the spatial distribution of air traffic, and its variation with time, in the Los Angeles Basin and at several locations from Boston to Washington, D.C. are reported. These measurements include only ATCRBS-transponder equipped aircraft. LA Basin traffic densities are shown to be significantly higher than those measured at any other location. The time- and spatial-average density over a circular region of 10 nmi radius reaches a peak value of 0.1 aircraft per sq. nmi in LA. Under comparable conditions the density in Washington, Philadelphia, and Boston reaches 0.02 to 0.04 aircraft per sq. nmi. These measurements, made in 1976, were compared with the LA Basin Standard Traffic Model as to spatial distribution of traffic and absolute density. The results show that the model and the measurement differ by a scale factor of 5:1 (with density being greater in the model) but otherwise agree closely in spatial distribution.
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Summary

Results of measurements to determine peak air traffic densities, the spatial distribution of air traffic, and its variation with time, in the Los Angeles Basin and at several locations from Boston to Washington, D.C. are reported. These measurements include only ATCRBS-transponder equipped aircraft. LA Basin traffic densities are shown to...

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Air traffic density and distribution measurements

MLS Multipath Studies, Phase 3, Volume I: Overview and Propagation Model Validation/Refinement Studies

April 25, 1979
  |
Project Report
Author:
James E. Evans
…
Published in:
MIT Lincoln Laboratory Report ATC-88,I
Topic:
surveillance
R&D area:
R&D group:

Summary

This report presents work done during phase 3 of the US national Microwave Landing System (MLS) program toward developing a computer simulation model of the MLS multipath effects, the experimental validation ot the model, and the application of the model to investigate multipath performance of ICAO proposals for the new approach and landing guidance system. This first volume of the report presents an overview of the overall simulation results as well as a description of the refined mathematical models and validation of the propagation portion of the simulation. Specific propagation topics include: 1) preliminary results for validation of models for reflections from rough and/or rising terrain based on L-band field data. 2) validation of the models for building reflections based on field measurements at a number of operational airports. 3) validation and refinement of the models for angle guidance system shadowing by obstacles such as buildings and other objects.
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Summary

This report presents work done during phase 3 of the US national Microwave Landing System (MLS) program toward developing a computer simulation model of the MLS multipath effects, the experimental validation ot the model, and the application of the model to investigate multipath performance of ICAO proposals for the new...

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MLS Multipath Studies, Phase 3, Volume I: Overview and Propagation Model Validation/Refinement Studies
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