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Wind information requirements for NextGen applications - phase 2 final report - framework refinement and application to four-dimensional trajectory based operations (4D-TBO) and interval management (IM)
May 20, 2014
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-418
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Summary
Accurate wind information is of fundamental importance to some of the critical future air traffic concepts under the FAA's Next Generation Air Transportation System (NextGen) initiative. Concepts involving time elements, such as Four-Dimensional Trajectory Based Operations (4D-TBO) and Interval Management (IM), are especially sensitive to wind information accuracy. There is a growing need to establish appropriate concepts of operation and target performance requirements accounting for wind information accuracy for these types of procedure, and meeting these needs is the purpose of this project. In the first phase of this work, a Wind Information Analysis Framework was developed to help explore the relationship of wind information to NextGen application performance. A refined version of the framework has been developed for the Phase 2 work that highlights the role stakeholders play in defining Air Traffic Control (ATC) scenarios, distinguishes wind scenarios into benign, moderate, severe, and extreme categories, and more clearly identifies what and how wind requirements recommendations are developed from the performance assessment trade-spaces. This report documents how this refined analysis framework has been used in Phase 2 of the work in terms of: -Refined wind information metrics and wind scenario selection process applicable to a broader range of NextGen applications, with particular focus on 4D-TBO and IM. -Expanded and refined studies of 4D-TBO applications with current Flight Management Systems (FMS) (with MITRE collaboration) to identify more accurate trade-spaces using operational FMS capabilities with higher-fidelity aircraft models. -Expansion of the 4D-TBO study using incremental enhancements possible in future FMSs (with Honeywell collaboration), specifically in the area of wind blending algorithms to quantify performance improvement potential from near-term avionics refinements. -Demonstrating the adaptability of the Wind Information Analysis Framework by using it to identify initial wind information needs for IM applications.
Summary
Accurate wind information is of fundamental importance to some of the critical future air traffic concepts under the FAA's Next Generation Air Transportation System (NextGen) initiative. Concepts involving time elements, such as Four-Dimensional Trajectory Based Operations (4D-TBO) and Interval Management (IM), are especially sensitive to wind information accuracy. There is...
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NextGen surveillance and weather radar capability (NSWRC) siting analysis
May 22, 2012
Project Report
Published in:
Project Report ATC-391, MIT Lincoln Laboratory
Summary
As the current radars that perform weather and aircraft surveillance over the United States age, they must be sustained through service life extension programs or replaced. In the latter case, the radars can be replaced by multiple types of radars with different missions or they can be replaced by scalable multifunction phased array radars (MPARs). State-of-the-art active phased array systems have the potential to provide improved capabilities such as earlier detection and better characterization of hazardous weather phenomena, 3D tracking of noncooperative aircraft, better avoidance of unwanted clutter sources such as wind farms, and more graceful performance degradation with component failure. As the U.S. aviation community works toward realizing the Next Generation Air Transportation System (NextGen), achieving improved capabilities for aircraft and weather surveillance becomes critical, because stricter observation requirements are believed to be needed. Hence, the Federal Aviation Administration (FAA) is considering the MPAR as a possible solution to their NextGen Surveillance and Weather Radar Capability (NSWRC). Cost is one hurdle to the deployment of a modern phased array radar network. One way of lowering the overall cost is to reduce the total number of radars. Because of the overlap in coverage provided by the current radar networks, a unified MPAR replacement network can potentially decrease the total number of radars needed to cover the same airspace. An earlier analysis conducted by MIT Lincoln Laboratory concluded that 510 legacy radars could be effectively replaced by 334 MPARs over the contiguous United States (CONUS). There was, however, some uncertainty whether the spatial resolution used in the terrain blockage calculations was fine enough to accurately depict radar coverage, and also if terminal area coverage was being adequately addressed. This study revisits the siting analysis using a much finer spatial resolution, expands the coverage domain to include all fifty states and U.S. territories, adds the Air Force long-range surveillance radars (FPSs) to the legacy pool, and allows scaling by number of faces per radar. The aim is to provide an estimate of the minimum number of MPARs needed to replace the existing radar coverage. We also provide an extensive statistical compilation of legacy versus MPAR coverage for various observational performance parameters.
Summary
As the current radars that perform weather and aircraft surveillance over the United States age, they must be sustained through service life extension programs or replaced. In the latter case, the radars can be replaced by multiple types of radars with different missions or they can be replaced by scalable...
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ASR-8/TDX-2000 performance analysis: evaluation of multiple-time-around-detection (MTAD) algorithm and final report
October 1, 2001
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-300
Summary
This report documents the analysis of and subsequent improvements to the performance of the ASR-8/TDX-2000 digitizer equipment combination. Working at the FAA's Palm Springs, CA and Williams (Mesa, AZ) ASR-8 facilities, data was methodically collected and analyzed to isolate the causes of reported correlated radar-only tracks that were being dropped or were never initiated. These problems were subsequently fixed via hard and soft parameter changes in the TDX-2000. A significant study was also undertaken in conjunction with the Sensis Corporation to improve the TDX-2000's capability to reject returns from multiple-time-around detections. The details of that algorithm modification and the results of follow-on testing and analysis are described. Final conclusions on the status of the project are also included.
Summary
This report documents the analysis of and subsequent improvements to the performance of the ASR-8/TDX-2000 digitizer equipment combination. Working at the FAA's Palm Springs, CA and Williams (Mesa, AZ) ASR-8 facilities, data was methodically collected and analyzed to isolate the causes of reported correlated radar-only tracks that were being dropped...
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Beacon radar and TCAS reply rates: airborne measurements in the 1090 MHz band
January 29, 1997
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-256
Summary
The Federal Aviation Administration (FAA) is in the process of developing Automatic Dependent Surveillance Broadcast (ADS-B) techniques. In one candidate system, GPS-Squitter, each aircraft periodically broadcasts messages, called "squitters," that report the aircraft's identification, position, and velocity. The position and velocity information may be obtained from the Global Positioning System (GPS) or some other navigation device. Reception of squitters can be used for several purposes, including surveillance of airborne aircraft by a ground station, surveillance of aircraft on the airport surface, and air-to-air surveillance... In developing the new system, it is necessary to know the rates of existing signal transmissions in the 1030 and 1090 MHz frequency bands, which are the beacon-radar and TCAS interrogation channels. The GPS-Squitter would be transmitted in the 1090 MHz band, like a reply. A key issue is the possibility of interference to squitter reception from existing signals in the 1090 MHz band....To validate these initial calculations, Lincoln Laboratory has made direct measurements of the rates of existing transmissions in both bands. These signals consist mainly of interrogations in the 1030 MHz band and replies in the 1090 MHz band. This report focuses on airborne measurements that have been made at 1090 MHz. (Not complete)
Summary
The Federal Aviation Administration (FAA) is in the process of developing Automatic Dependent Surveillance Broadcast (ADS-B) techniques. In one candidate system, GPS-Squitter, each aircraft periodically broadcasts messages, called "squitters," that report the aircraft's identification, position, and velocity. The position and velocity information may be obtained from the Global Positioning System...
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GPS-squitter capacity analysis
May 20, 1994
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-214
Summary
GPS-Squitter is a system concept that merges the capabilities of Automatic Dependent SurveiIlance (ADS) and the Mode S beacon radar. The resuit is an integrated concept for seamless surveillance and data link that permits equipped aircraft to participate in ADS and/or beacon ground environments. This concept offers many possibilities for transition from a beacon to an ADS-based environment. This report provides the details of the techniques used to estimate GPS-Squitter surveillance and data link capacity. Surveillance capacity of airborne aircraft is calculated for the omni and six-sector ground stations. Next, the capacity of GPS-Squitter for surface traffic is estimated. The interaction between airborne and surface operations is addressed to show de independence of these systems. Air ground data link capacity for GPS-Squitter is estimated, together with an estimate of the use of the Mode S link to support other ground surveillance and data link activities as well as TCAS operation. The analysis indicates the low transponder occupancy resulting from the total effect of these activities. Low occupancy is a key requirement in avoiding interference with the operation of the current ATCRRS and future Mode S interrogators.
Summary
GPS-Squitter is a system concept that merges the capabilities of Automatic Dependent SurveiIlance (ADS) and the Mode S beacon radar. The resuit is an integrated concept for seamless surveillance and data link that permits equipped aircraft to participate in ADS and/or beacon ground environments. This concept offers many possibilities for...
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The Memphis Precision Runway Monitor Program Instrument Landing System final approach study
May 24, 1993
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-194
Summary
This report documents the study of the lateral positions of aircraft on Instrument Landing System (ILS) approaches during the Memphis, Tennessee, Precision Runway Monitor (PRM) demonstration. The PRM is an advanced radar monitoring system that improved the arrival capacity of closely spaced parallel runways in poor weather conditions. The results of this study are used to assist in determining the minimum runway spacing that will he authorized for PRM. The objective of this study was to quantify the lateral character of ILS arrivals and the consequent impact on independent simultaneous ILS arrival to closely spaced parallel runways. The sensitivity of the arriving aircrafts' lateral positions to different variables such as visibility, wind runway, aircraft type, autopilot performance, and localizer beam width was determined. Also, the Memphis arrival data were compared to FAA Technical Center Chicago O'Hare approach data. The analysis was primarily based on surveillance reports of 4,000 ILS arrivals into Memphis International Airport, collected with the PRM AMPS sensor (ATCRBS Monopulse Processing System). A major result of the study was that lateral aircraft positions will not hamper independent arrivals to parallel runways spaced 3,400 feet apart, but will impede operations at 3,000 feet or smaller unless approach modifications are introduced. Lateral deviations were found to be most sensitive to reduced visibility and certain autopilots. Lateral deviations were also found to be somewhat more at Memphis relative to Chicago O'Hare. Recommendations for further data analysis and collection are discussed.
Summary
This report documents the study of the lateral positions of aircraft on Instrument Landing System (ILS) approaches during the Memphis, Tennessee, Precision Runway Monitor (PRM) demonstration. The PRM is an advanced radar monitoring system that improved the arrival capacity of closely spaced parallel runways in poor weather conditions. The results...
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ADS-Mode S: Initial System Description
April 2, 1993
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-200
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Summary
Dependent Surveillance and the Mode S beacon radar. The result is an integrated concept for seamless surveillance and data link that permita equipped aircraft to participate in ADS or beacon ground environmenta. This offers many possibilities for transition from a beacon to an ADS based environment. The ADS-Mode S concept in baaed on use of the Mode S squitter. The Mode S squitter is a spontaneous, periodic (once per second) 56-bit Mode S broadcast containing the Mode S 24-bit address. This broadcast is provided by all Mode S transponders and in used by the Traffic Alert and Collision Avoidance System (TCAS) to acquire Mode S equipped aircraft. For ADS-Mode S use, this squitter broadcast is extended to 112 bits to provide for the transmission of a 56-bit ABS message field. The ADS squitter is transmitted in addition to the current TCAS squitter in order to maintain compatibility with current TCAS equipment. This paper defines the ADS-Mode S concept, describes its principal surveillance and data link applications and provides estimates of expected performance.
Summary
Dependent Surveillance and the Mode S beacon radar. The result is an integrated concept for seamless surveillance and data link that permita equipped aircraft to participate in ADS or beacon ground environmenta. This offers many possibilities for transition from a beacon to an ADS based environment. The ADS-Mode S concept...
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Preliminary Memphis FAA/Lincoln Laboratory operational weather studies results
April 22, 1987
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-141
Summary
During 1984 and 1985 M.I.T. Lincoln Laboratory, under the sponsorship of the Federal Aviation Administration (FAA) conducted a measurement program in the Memphis, Tennessee, area to study low-level wind shear events and other weather phenomena that are potentially hazardous to aircraft operations, with particular emphasis on those issues related to the Terminal Doppler Weather Radar (TDWR). The principal sensor for the measurement program was the S-band FAA-Lincoln Laboratory Testbed Doppler Weather Radar (FL2) which incorporates many of the functional features of the TDWR. Both FL2 and a C-band Doppler Weather Radar operated by the University of North Dakota (UND) obtained reflectivity, mean velocity and spectrum width measurements with a radar geometry and scan sequences to facilitate determining the surface outflow features of microbursts at the anticipated TDWR ranges. A 30-station network of automatic weather stations (mesonet) collected I-min averages of temperature, humidity, pressure, wind speed and direction, and total rainfall, plus the peak wind speed during each minute; this system operated from about March through November 1984 and 1985. Finally, the UND Citation aircraft operated two 3-week periods during 1985, collecting thermodynamical, kinematical and microphysical data within and around selected storms in the area as well as providing in situ truth for locations and intensity of turbulence. This report describes the principal initial results from the Memphis operations, stressing the results from 1985 when the FL2 radar was fully operational. These results are compared to those from previous studies of wind-shear programs, e.g., NIMROD near Chicago, JAWS and CLAWS near Denver. During 1985, 102 microbursts were identified in real time along with 81 gust fronts. One of the dominant results is that most microbursts in the mid-south are wet; that is, they are accompanied by significant rainfall. This is in contrast, for example, to the results from Denver where more than half of all microbursts have little or no appreciable rain reaching the ground. Aside from this major difference, microbursts near Memphis were similar to those found elsewhere in the country in terms of wind shear magnitude. The report also gives more representative results from the aircraft operations and discusses the effectiveness of the ground-clutter filters used on the FL2 radar.
Summary
During 1984 and 1985 M.I.T. Lincoln Laboratory, under the sponsorship of the Federal Aviation Administration (FAA) conducted a measurement program in the Memphis, Tennessee, area to study low-level wind shear events and other weather phenomena that are potentially hazardous to aircraft operations, with particular emphasis on those issues related to...
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Mode S beacon system: functional description (revision D)
August 29, 1986
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-42-D
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Summary
This document provides a functional description of the Mode S Beacon System, a combined secondary surveillance radar (beacon) and ground-air-ground data link system capable of providing the aircraft surveillance and communications necessary to support ATC automation in future traffic environments. Mode S is capable of common-channel interoperation with the current ATC beacon system, and may be implemented at low user cost over an extended transition period. Mode S will provide the surveillance and communication performance required by the ATC automation, the reliable communications needed to support data link services, and the capability of operating with a terminal or enroute, radar digitizer-equipped, ATC surveillance radar. The material contained in this document updates and expands the information presented in "Mode S Beacon System: Functional Description", DOT/FAA/PM-83/8, 215 July 1983.
Summary
This document provides a functional description of the Mode S Beacon System, a combined secondary surveillance radar (beacon) and ground-air-ground data link system capable of providing the aircraft surveillance and communications necessary to support ATC automation in future traffic environments. Mode S is capable of common-channel interoperation with the current...
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Effect of interference on the performance of a minimum TCAS II
September 5, 1985
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-132
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Summary
Minimum TCAS II equipment is required to operate reliably in all aircraft densities up to the 0.3 transponder-equipped aircraft per square nautical mile anticipated in the Los Angeles Basin in the year 2000. Prototype TCAS equipment has been developed and shown to be capable of providing reliable surveillance in today's highest densities, which reach an average of about 0.1 aircraft per square nmi. Since there are no existing environments that reach the density of asynchronous interference anticipated for the Los Angeles Basin in the year 2000, it is necessary to generate simulated interference to determine the performance of the TCAS II design in that environment. A series of bench tests were conducted at Lincoln Laboratory for this purpose. Special sources were used to generate asynchronous ATCRBS and Mode S reply signals (Fruit) and TCAN/DME squitter and interrogation signals. Synchronous ATCRBS and Mode S reply sequences were also generated to simulate airborne encounters. The performance was evaluated by observing hoe the interference signals either degraded the ability of a TCAS II unit to receive, process, and track the desired synchronous reply sequences, or caused the TCAS II unit to generate false tracks.
Summary
Minimum TCAS II equipment is required to operate reliably in all aircraft densities up to the 0.3 transponder-equipped aircraft per square nautical mile anticipated in the Los Angeles Basin in the year 2000. Prototype TCAS equipment has been developed and shown to be capable of providing reliable surveillance in today's...
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