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Evaluation of the MTD in a high-clutter environment

January 1, 1980
  |
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
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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
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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

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

April 25, 1979
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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

The DABS calibration performance monitoring equipment

March 23, 1979
  |
Project Report
Author:
James C. Anderson
Published in:
MIT Lincoln Laboratory Report ATC-89
Topic:
surveillance
R&D area:
R&D group:

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 DABS calibration performance monitoring equipment

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

February 28, 1979
  |
Project Report
Author:
Ferenc Nagy Jr
Published in:
MIT Lincoln Laboratory Report ATC-83,II
Topic:
surveillance
R&D area:
R&D group:

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

Automated tracking for aircraft surveillance radar systems

January 1, 1979
  |
Conference Paper
Author:
Robert M. O'Donnell
…
Published in:
IEEE Trans. Aerosp. Electron. Syst., Vol. AES-15, No. 4, July 1979, pp. 508-517.
Topic:
detection systems
R&D area:
R&D group:

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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Automated tracking for aircraft surveillance radar systems

Airborne measurements of ATCRBS fruit

October 3, 1978
  |
Project Report
Author:
William H. Harman III
Published in:
MIT Lincoln Laboratory Report ATC-84
Topic:
surveillance
R&D area:
R&D group:

Summary

Airborne measurements of ATCRBS fruit (asynchronous replies from ATCRBS transponders) are described. These measurements were undertaken to provide a more firm basis for assessing the interference impact of ATCRBS fruit on airborne 1090 MHz receivers (as in BCAS). Fruit rate measurements were performed with an instrumented aircraft flying along the East Coast from Boston to Washington and in the Los Angeles Basin. The results of these measurements are reported here, with fruit rates given as a function of altitude, geographical location, and receiver threshold, for receptions on both top-mounted and bottom-mounted aircraft antenna. The highest observed fruit rates, approximately 10,000 replies/sec, occurred in the LA Basin. To complement the measurements, a first-order fruit prediction model is defined. Predictions of this model are compared with the measurements, generally showing favorable agreement in absolute fruit rate, in power distribution, and in the functional dependence on traffic density.
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Summary

Airborne measurements of ATCRBS fruit (asynchronous replies from ATCRBS transponders) are described. These measurements were undertaken to provide a more firm basis for assessing the interference impact of ATCRBS fruit on airborne 1090 MHz receivers (as in BCAS). Fruit rate measurements were performed with an instrumented aircraft flying along the...

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Airborne measurements of ATCRBS fruit

Uplink ATCRBS environment measurements along the Boston-Washington Corridor, volume 1: the RF environment

June 27, 1978
  |
Project Report
Author:
Ferenc Nagy Jr
Published in:
MIT Lincoln Laboratory Report ATC-83,I
Topic:
surveillance
R&D area:
R&D group:

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 and processed to obtain distributions of pulse, interrogation, and suppression rates with received power. The most numerous contributors to the uplink pulse environment are omnidirectionally radiated suppression pulses. The overall average suppression rate is approximately 600 per second. The suppression rate is relatively independent of altitude but there are wide variations in the suppression rate from one location to another. Interrogation rates increase with altitude but do not vary significantly from location to location except near interrogators without sidelobe suppression. The overall average rate of receipt of Mode A plus Mode C interrogations is approximately 75 per second at an altiude of 8500 feet and 100 per second at an altitude of 17,500 feet.
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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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Uplink ATCRBS environment measurements along the Boston-Washington Corridor, volume 1: the RF environment

Simulation of surveillance and processing algorithms proposed for the DABS mode of BCAS

February 16, 1978
  |
Project Report
Author:
Patricia H. Mann
Published in:
MIT Lincoln Laboratory Report ATC-82
Topic:
surveillance
R&D area:
R&D group:

Summary

Surveillance Processing Algorithms for the DABS Mode of BCAS have been implemented in software for the non-real time processing of air-to-air link data. The data to be processed may be either AMF recorded air-to-air data, or data derived from simulated flight encounters. Examples of simulation trials for a specific collision encounter are presented with illustrate the impact of increased ATCRBS fruit levels upon the performance of the surveillance processor. This document also provides detailed definitions of the surveillance processing algorithms.
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Summary

Surveillance Processing Algorithms for the DABS Mode of BCAS have been implemented in software for the non-real time processing of air-to-air link data. The data to be processed may be either AMF recorded air-to-air data, or data derived from simulated flight encounters. Examples of simulation trials for a specific collision...

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Simulation of surveillance and processing algorithms proposed for the DABS mode of BCAS
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