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

Author:
Published in:
MIT Lincoln Laboratory Report ATC-92

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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Discrete address beacon system data link

Published in:
3rd Digital Avionics Sys. Conf., 6-7 Nov. 1979, pp. 117-121.

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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Air traffic density and distribution measurements

Published in:
MIT Lincoln Laboratory Report ATC-80

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

Published in:
MIT Lincoln Laboratory Report ATC-88,I

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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The DABS calibration performance monitoring equipment

Published in:
MIT Lincoln Laboratory Report ATC-89

Summary

The Discrete Address Beacon System (DABS) Calibration Performance Monitor Equipment (CPME) is a special DABS transponder designed for installation at a fixed site visible to one or more DABS beacon sensors. The CPME is required for DABS sensor monopulse accuracy tests and for calibration of the sensor off-boresite azimuth look-up table. In addition, the CPME provides tests for DABS link integrity, by storing an uplink message and parroting it back upon command from the sensor. This document contains all information necessary to obtain a general understanding of the CPME system and its operation. Detailed information necessary for repair of the equipment is not contained in this document, but is supplied with each CPME system.
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Summary

The Discrete Address Beacon System (DABS) Calibration Performance Monitor Equipment (CPME) is a special DABS transponder designed for installation at a fixed site visible to one or more DABS beacon sensors. The CPME is required for DABS sensor monopulse accuracy tests and for calibration of the sensor off-boresite azimuth look-up...

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The Aircraft Reply and Interference Environment Simulator (ARIES) volume 1: principles of operation

Author:
Published in:
MIT Lincoln Laboratory Report ATC-87,I

Summary

The Aircraft Reply and Interference Environment Simulator (ARIES) makes possible the performance assessment of a Discrete Address Beacon System (DABS) sensor under its specified maximum aircraft load. To do this ARIES operates upon a taped traffic model to generate simulated aircraft replies and fruit, feeding them to the sensor at RF. Support documentation for ARIES, of which this is the first volume, consists of: Volume 1: Principles of Operation Volume 2: Appendices to the Principles of Operation Volume 3: Programmer's Manual The Principles of Operation details the operation of ARIES hardware and software. Descriptive information, supported by block diagrams, simplified schematic diagrams and flow diagrams, is provided sufficient to permit a thorough understanding of ARIES operation.
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Summary

The Aircraft Reply and Interference Environment Simulator (ARIES) makes possible the performance assessment of a Discrete Address Beacon System (DABS) sensor under its specified maximum aircraft load. To do this ARIES operates upon a taped traffic model to generate simulated aircraft replies and fruit, feeding them to the sensor at...

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The Aircraft Reply and Interference Environment Simulator (ARIES) volume 3: programmer's manual

Author:
Published in:
MIT Lincoln Laboratory Report ATC-87,III

Summary

The Aircraft Reply and Interference Environment Simulator (ARIES) makes possible the performance assessment of a Discrete Address Beacon System (DABS) sensor under its specified maximum aircraft load. To do this ARIES operates upon a taped traffic model to generate simulated aircraft replies and fruit, feeding them to the sensor at RF. Support documentation for ARIES, of which this is the second volume, consists of: Volume 1: Principles of Operation Volume 2: Appendices to the Principles of Operation Volume 3: Programmer's Manual The ARIES Programmer's Manual describes the operation, signal formats and protocols of the Lincoln Laboratory built input/output devices controlled by the Eclipse computer. The descriptions are primarily concerned with the logic of the interface boards that reside in the computer chassis and the formats of the words transferred to and from the computer. The logic of the devices themselves is described only to the extent necessary to understand the interface protocols and data formats.
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Summary

The Aircraft Reply and Interference Environment Simulator (ARIES) makes possible the performance assessment of a Discrete Address Beacon System (DABS) sensor under its specified maximum aircraft load. To do this ARIES operates upon a taped traffic model to generate simulated aircraft replies and fruit, feeding them to the sensor at...

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The Aircraft Reply and Interference Environment Simulator (ARIES), volume 2: appendices to the principles of operation

Author:
Published in:
MIT Lincoln Laboratory Report ATC-87,II

Summary

The Aircraft Reply and Interference Environment Simulator (ARIES) makes possible the performance assessment of a Discrete Address Beacon System (DABS) sensor under its specified maximum aircraft load. To do this ARIES operates upon a taped traffic model to generate simulated aircraft replies and fruit, feeding them to the sensor at RF. Support documentation for ARIES, of which this is the second volume, consists of: Volume 1: Principles of Operation Volume 2: Appendices to the Principles of Operation Volume 3: Programmer's Manual The Appendices to the Principles of Operation is comprised of a set of technical articles providing (a) explanations of design and programming aspects of the ARIES system not covered in the main volume, (b) detailed data format and data structure definitions, (c) detailed explanations of the meaning of ARIES error messages, and (d) an analysis of certain effects to be expected when more than one ARIES simulator are interconnected.
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Summary

The Aircraft Reply and Interference Environment Simulator (ARIES) makes possible the performance assessment of a Discrete Address Beacon System (DABS) sensor under its specified maximum aircraft load. To do this ARIES operates upon a taped traffic model to generate simulated aircraft replies and fruit, feeding them to the sensor at...

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Uplink ATCRBS environment measurements along the Boston-Washington corridor, volume 2: interrogator characteristics

Author:
Published in:
MIT Lincoln Laboratory Report ATC-83,II

Summary

Airborne measurements of the Air Traffic Control Radar Beacon System (ATCRBS) 1030 MHz uplink environment due to ATC ground interrogators are described. The measurements were made using a special purpose airborne sensor-recorder during a flight from Boston to Washington (at 8500 feet) and back (at 17,500 feet) on 16 December 1977. Data were recorded at 24 locations between Boston and Washington. Volume 1 of this report summarized the measured distributions of pulse, interrogation, and suppression rates with received power. This volume presents specific characteristics of the sources of the interrogations observed from the air dUring this flight. These characteristics include the identities of 46 of the interrogators, the approximate locations of 22 unidentified interrogators, the interrogation repetition interval (PRI), scan period, and mode interlace of all interrogators, and the radiated P1, P2, and P3 levels in the form of antenna patterns for six selected interrogators. It was found that approximately 40% of the interrogators employ the standard AAC or 2ACA mode interlaces while 20% transmit no Mode C interrogations. The distributions of PRI's and scan periods were found to be relatively free of bunching which would cause undesired synchronization effects. The antenna plots measured from the air show relatively large scan to scan variations due to aircraft motion. In addition, some of the interrogator sites were found to suffer from reflections and sidelobe punch-through effects.
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Summary

Airborne measurements of the Air Traffic Control Radar Beacon System (ATCRBS) 1030 MHz uplink environment due to ATC ground interrogators are described. The measurements were made using a special purpose airborne sensor-recorder during a flight from Boston to Washington (at 8500 feet) and back (at 17,500 feet) on 16 December...

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Automated tracking for aircraft surveillance radar systems

Published in:
IEEE Trans. Aerosp. Electron. Syst., Vol. AES-15, No. 4, July 1979, pp. 508-517.

Summary

An improved moving target detector (MTD) (a digital signal processor) has been designed, constructed, and tested which successfully rejects all forms of radar clutter while providing reliable detection of all aircraft within the coverage of the radar. The MTD is being tested on both terminal and enroute surveillance radars for the FAA. This processor has been integrated with automatic tracking algorithms to give complete rejection of ground clutter, heavy precipitation, and angels (birds).
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Summary

An improved moving target detector (MTD) (a digital signal processor) has been designed, constructed, and tested which successfully rejects all forms of radar clutter while providing reliable detection of all aircraft within the coverage of the radar. The MTD is being tested on both terminal and enroute surveillance radars for...

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