Publications
WSP utility libraries
October 23, 2000
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-284
Summary
The ASR-9 Weather Systems Processor (WSP) augments the weather detection capability of existing ASR-9 radars to include low-level wind shear warnings, storm cell tracking and prediction, and improved immunity to false weather echoes due to anomalous propagation (AP). To economically develop and field an operational system at the 34 WSP sites, the FAA is pursuing a strategy that leverages the software written during the 10-year R&D phase of the project. To that end, the software developed at Lincoln Laboratory has been "hardened" to ensure reliable, continuous operation, and has been ported to a "Phase II" prototype built around the latest generation of COTS hardware. A significant number of the hardened software modules are being used in the production version of the WSP with only minor modifications. Included as part of the software are a number of lower-level utility libraries to provide basic services such as memory management and network communication. This document provides a detailed description of these common utility libraries.
Summary
The ASR-9 Weather Systems Processor (WSP) augments the weather detection capability of existing ASR-9 radars to include low-level wind shear warnings, storm cell tracking and prediction, and improved immunity to false weather echoes due to anomalous propagation (AP). To economically develop and field an operational system at the 34 WSP...
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Common CHI for en route ATC automation in FFP1 and beyond
October 22, 2000
Conference Paper
Published in:
45th Annual Air Traffic Control Association Conf. Proc., 22-26 October 2000, pp. 237-241.
Summary
Unique computer-human interface (CHI) challenges are arising with the pending deployment of automation developed to assist air traffic controllers and managers. In the US, a set of Free Flight Phase 1 (FFPl) decision-support tools will provide computer generated scheduling and sequencing advice from Traffic Management Advisor (TMA) and conflict probing advice from User Request Evaluation Tool (URET). These tools were originally developed independently using their own CHIs. Recently, the air traffic community requested that future tools be implemented as an integrated functionality with a consistent look and feel modeled on Eurocontrol's innovative Operational Display and Input Development (ODID) IV. M.I.T. Lincoln Laboratory presented an initial comparative study of FAA and Eurocontrol tools that identified several key inconsistencies between the newly deployed Display System Replacement (DSR), the upcoming FFPl and the future ODID-like CHIs at ATCA 1999. This paper expands the survey to add the ETMS Traffic Situation Display (TSD) and to include a comparison of all look and feel aspects of each tool ranging from the purpose and system requirements to the display and coordination features. Excerpts from the completed survey are presented in Table 1, accompanied by preliminary descriptions of resulting human factors issues that need resolution to achieve a common CHI for future air traffic control and management. In support of the FAA, the Laboratory is now applying the findings from this effort and previous controller testing in collaboration with MITRE CAASD to identify and assess CHI features to be used for a demonstration of integrated operational concepts. This effort, along with continued CHI requirements testing, communication with FAA vendors and concept demonstrations conducted in coordination with the air traffic community will lead to a comprehensive list of prioritized issues regarding a common CHI.
Summary
Unique computer-human interface (CHI) challenges are arising with the pending deployment of automation developed to assist air traffic controllers and managers. In the US, a set of Free Flight Phase 1 (FFPl) decision-support tools will provide computer generated scheduling and sequencing advice from Traffic Management Advisor (TMA) and conflict probing...
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ASR-9 weather systems processor software overview
October 20, 2000
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-264
Summary
The ASR-9 Weather Systems Processor (WSP) augments the weather detection capability of existing ASR-9 radars to include low-level wind shear warnings, storm cell tracking and prediction, and improved immunity to false weather echoes due to anomalous propagation (AP). To economically develop and field an operational system at the 34 WSP sites, the FAA is pursuing a strategy that leverages the software written during the 10-year R&D phase of the project. To that end, the software developed at Lincoln Laboratory has been "hardened" to ensure reliable, continuous operation, and has been ported to a "Phase II" prototype built around the latest generation of COTS hardware. A significant number of the hardened software modules are being used in the production version of the WSP with only minor modifications. This document provides a high-level description of these software modules, with an emphasis on how the modules fit together in the WSP system. Descriptions of the hardware environment in which the software executes are also provided.
Summary
The ASR-9 Weather Systems Processor (WSP) augments the weather detection capability of existing ASR-9 radars to include low-level wind shear warnings, storm cell tracking and prediction, and improved immunity to false weather echoes due to anomalous propagation (AP). To economically develop and field an operational system at the 34 WSP...
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Comparison of active TCAS slant range measurements with interpolated passive position reports for use in hybrid surveillance applications - measurements from the June 1999 Los Angeles Basin flight tests
October 17, 2000
Project Report
Published in:
MIT Lincoln Laboratory Report ATC-294
Summary
Traffic Alert and Collision Avoidance System (TCAS) hybrid surveillance is a technique that makes use of both active surveillance data from the interrogation reply sequence and passive position estimates received from Mode S extended squitters. This technique allows TCAS to use passive surveillance once the data have been validated by comparison with active data. The maximum allowable range difference for validation specified by the International Civil Aviation Organization (ICAO) is 200 meters. Data from twenty encounters recorded during flight tests conducted in the Los Angeles Basin in June 1999 were analyzed. The results show that the ICAO specified limits were never exceeded and serve to validate the 200 meter limit.
Summary
Traffic Alert and Collision Avoidance System (TCAS) hybrid surveillance is a technique that makes use of both active surveillance data from the interrogation reply sequence and passive position estimates received from Mode S extended squitters. This technique allows TCAS to use passive surveillance once the data have been validated by...
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The Lincoln speaker recognition system: NIST EVAL2000
October 16, 2000
Conference Paper
Published in:
6th Int. Conf. on Spoken Language, ICSLP, 16-20 October 2000.
Topic:
R&D area:
Summary
This paper presents an overview of the Lincoln Laboratory systems fielded for the 2000 NIST speaker recognition evaluation (SRE00). In addition to the standard one-speaker detection tasks, this year's evaluation, as in 1999, included multi-speaker spokes dealing with detection, tracking and segmentation. The design approach for the Lincoln system in SRE00 was to develop a set of core one-speaker detection and multi-speaker clustering tools that could be applied to all the tasks. This paper will describe these core systems, how they are applied to the SRE00 tasks and the results they produce. Additionally, a new channel normalization technique known as handset-dependent test-score norm (HTnorm) is introduced.
Summary
This paper presents an overview of the Lincoln Laboratory systems fielded for the 2000 NIST speaker recognition evaluation (SRE00). In addition to the standard one-speaker detection tasks, this year's evaluation, as in 1999, included multi-speaker spokes dealing with detection, tracking and segmentation. The design approach for the Lincoln system in...
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A statistical analysis of approach winds at capacity-restricted airports
October 7, 2000
Conference Paper
Published in:
19th AIAA/IEEE Digital Avionics Systems Conf., Vol. 1, 7-13 October 2000, pp. 3.E.4-1 - 3.E.4-7.
Summary
Many major airports in the U.S. rely on simultaneous approaches to closely-spaced parallel (CSP) runways to maintain a high airport acceptance rate. During Visual Meteorological Conditions (VMC), aircraft are able to utilize both runways by making side-by-side landings and are able to meet the demands of heavy volume. However, when conditions deteriorate to marginal-VMC or Instrument Meteorological Conditions (IMC), side-by-side approaches are not possible due to the inherent safety concerns associated with lowered ceilings and visibilities. This situation is severely limiting to an airport's capacity and can create large delays and increased costs. Various ideas have been suggested that would facilitate the simultaneous use of CSP runways during low ceiling and visibility (LCV) conditions at capacity-restricted airports. This report addresses the specific scenario of a pair of approaching aircraft being staggered by some longitudinal distance. This situation alleviates the collision hazard presented by LCV conditions, but also introduces the hazard of a wake vortex encounter, particularly if the following aircraft is downwind of the leading aircraft.
Summary
Many major airports in the U.S. rely on simultaneous approaches to closely-spaced parallel (CSP) runways to maintain a high airport acceptance rate. During Visual Meteorological Conditions (VMC), aircraft are able to utilize both runways by making side-by-side landings and are able to meet the demands of heavy volume. However, when...
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Measurements of ADS-B extended squitter performance in the Los Angeles basin region
October 7, 2000
Conference Paper
Published in:
19th AIAA/IEEE Digital Avionics Systems Conf., Vol. 2, 7-13 October 2000, pp. 7.B.1-1 - 7.B.1-8.
Summary
The Los Angeles Basin ADS-B Measurement Trials provided a quantitative assessment of the existing interference environment at 1090 MHz and the surveillance performance of Mode S Extended Squitter in that environment. Redundancy in the measurement equipment and in the flight configurations chosen during the trials provided extensive cross checking capability, and greatly increased the integrity of the results. ATCRBS reply rates as high as 40,000/second above -90 dBm were measured. The corresponding aircraft distribution and 1030 MHz interrogation rates correlated well with these measurements. A wide range of scenarios were captured to measure the airborne and ground-based reception of ADS-B Extended Squitters emitted by airborne sources. Air-to-air ranges of greater than 100 nmi were routinely observed, and comparison with ADS-B MASPS requirements showed that all airborne requirements were met in the scenarios flown. Air-to-ground reception rates were routinely better than the update rates provided by either en route or terminal radars at ranges beyond 150 nmi. Ground-to-air (uplink) performance was adequate to support transmission of ADS-B or other information in broadcast formats within approximately 60 nmi of the ground station. Finally, these measurements are a valuable source of validation and refinement data for the various models used to predict Extended Squitter performance in current and future scenarios.
Summary
The Los Angeles Basin ADS-B Measurement Trials provided a quantitative assessment of the existing interference environment at 1090 MHz and the surveillance performance of Mode S Extended Squitter in that environment. Redundancy in the measurement equipment and in the flight configurations chosen during the trials provided extensive cross checking capability...
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Open system protocols for aviation data link applications
October 7, 2000
Conference Paper
Published in:
19th AIAA/IEEE Digital Avionics Systems Conf., Vol. 2, 7-13 October 2000.
Summary
This paper will discuss the application of "open system" communications protocols in the design and implementation of data link applications for aviation. The term "open system" in this paper refers to a set of communications protocols whose design specification is readily open to the user community, usually via publication by an international standards body. Such open system standards tend to encourage widespread implementation and enhancement of the communications protocols defined in the open standards. Ready availability of well-tested implementations helps to keep the costs of open systems low. Interoperability of equipment is enhanced by the use of open systems, as is the ease of system extensibility. In some cases, system communications infrastructures to support the open system may already be in place (e.g. the Internet). Data link applications in aviation are increasing at an accelerating rate. Whether for air traffic control, airline operations, or improved pilot situational awareness, data link systems are required for many existing and future functions in aviation. Many aviation data link designs have been proposed and demonstrated over the years. A drawback to most of these designs is their ad hoc nature. It is difficult to combine the various aviation data links into a coherent overall system architecture. Since each aviation data link was specialized for a specific task or application, there is little commonality of design, nor is there much opportunity for software/hardware reuse in ground or avionics equipment. Each aviation data link has required its own separate system infrastructure - leading to considerable overlap, complexity, and expense. At the same time, the Internet community has seen explosive growth in both the number of Internet users and the types of Internet system applications. Much of this growth may be tied to the "open system" nature of the Internet communications protocols which allows for straightforward implementation of Internet applications. It is difficult to buy a computer today that doesn't have an Internet protocol stack in its system software. Extremely inexpensive Internet implementations are in everything from microwave ovens to laptops. The Internet's dramatic growth is an indicator of the power of "open system" architecture to encourage development of communications applications. This paper will show how the use of suitable open system communications protocols can help to bring increased efficiency and lower-cost equipment to aviation data link systems.
Summary
This paper will discuss the application of "open system" communications protocols in the design and implementation of data link applications for aviation. The term "open system" in this paper refers to a set of communications protocols whose design specification is readily open to the user community, usually via publication by...
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Multilateration system development history and performance at Dallas/Ft. Worth Airport
October 7, 2000
Conference Paper
Published in:
19th AIAA/IEEE Digital Avionics Systems Conf., Vol. 1, 7-13 October 2000, pp. 2.E.1-1 - 2.E.1-8.
Summary
The long search for a method to provide accurate secondary radar beacon surveillance with aircraft ID over the whole airport surface has succeeded, using the Mode S squitter and whisper shout technologies to provide signal sources on which to make multilateration position measurements. The resulting multilateration system will greatly improve the situational awareness of the ground controllers, and provide inputs to automation functions, providing improvements in airport safety and capacity.
Summary
The long search for a method to provide accurate secondary radar beacon surveillance with aircraft ID over the whole airport surface has succeeded, using the Mode S squitter and whisper shout technologies to provide signal sources on which to make multilateration position measurements. The resulting multilateration system will greatly improve...
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SOI wafer selection for CCD/SOI-CMOS technology [Abstract]
October 2, 2000
Conference Paper
Published in:
2000 IEEE Int. SOI Conf. Proc., 2-5 October 2000, pp. 136-137.
Summary
We have developed a process that monolithically integrates fully depleted SOI CMOS (FDSOI) with high-performance CCD image sensors. This integrated technology that enables charged-coupled devices (CCD's) to be in close proximity to, yet isolated from, FDSOI circuits. This approach exploits both the advantages of FDSOI (fast, low-power CMOS with potentially enhanced radiation performance) and those of CCD's (high quantum efftciency, low noise, and architectural flexibility). This 3.3 V, 0.3 mu m CCD/FDSOI-CMOS technology thus enables fabrication of low-power, compact imaging systems. Material requirements for CCD imagers are perhaps the most stringent of any device and require special attention to the quality of the bulk or handle wafer. We report here characterization of various SOI handle wafers for use in fabrication of bulk imaging devices.
Summary
We have developed a process that monolithically integrates fully depleted SOI CMOS (FDSOI) with high-performance CCD image sensors. This integrated technology that enables charged-coupled devices (CCD's) to be in close proximity to, yet isolated from, FDSOI circuits. This approach exploits both the advantages of FDSOI (fast, low-power CMOS with potentially...
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