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A constrained joint optimization approach to dynamic sensor configuration

Author:
Published in:
36th Asilomar Conf. on Signals, Systems, and Computers, Vol. 2, 3-6 November 2002, pp. 1179-1183.

Summary

Through intelligent integration of sensing and processing functions, the sensing technology of the future is evolving towards networks of configurable sensors acting in concert. Realizing the potential of collaborative real-time configurable sensor systems presents a number of challenges including the need to address a number of challenges including the need to address the massive global optimization problem resulting from incorporating a large array of control parameters. This paper proposes a systematic approach to addressing complex global optimization problems by constraining the problem to a set of key control parameters and recasting a mission-oriented goal into a tractable joint optimization formula. Using idealized but realistic physical models, a systematic methodology to approach complex multi-dimensional joint optimization problems is used to compute system performance bounds for dynamic sensor configurations.
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Summary

Through intelligent integration of sensing and processing functions, the sensing technology of the future is evolving towards networks of configurable sensors acting in concert. Realizing the potential of collaborative real-time configurable sensor systems presents a number of challenges including the need to address a number of challenges including the need...

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Silicon-on-insulator-based single-chip image sensors: low-voltage scientific imaging

Published in:
Experimental Astronomy, Vol. 14, No. 2, 2002, pp. 91-98.

Summary

A low-voltage (
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Summary

A low-voltage (

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Soft-x-ray CCD imagers for AXAF

Published in:
IEEE Trans. Electron Devices, Vol. 44, No. 10, October 1997, pp. 1633-1642.

Summary

We describe the key features and performance data of a 1024 x 1026-pixel frame-transfer imager for use as a soft-x-ray detector on the NASA X-ray observatory Advanced X-ray Astrophysics Facility (AXAF). The four-port device features a floating-diffusion output circuit with a responsivity of 20/spl mu/V/e/sup -/ and noise of about 2 e/sup -/ at a 100-kHz data rate. Techniques for achieving the low sense-node capacitance of 5 fF are described. The CCD is fabricated on high-resistivity p-type silicon for deep depletion and includes narrow potential troughs for transfer inefficiencies of around 10/sup -7/ (ten to the negative 7). To achieve good sensitivity at energies below 1 keV, we have developed a back-illumination process that features low recombination losses at the back surface and has produced efficiencies of about 0.7 at 277 eV (carbon K/spl alpha/).
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Summary

We describe the key features and performance data of a 1024 x 1026-pixel frame-transfer imager for use as a soft-x-ray detector on the NASA X-ray observatory Advanced X-ray Astrophysics Facility (AXAF). The four-port device features a floating-diffusion output circuit with a responsivity of 20/spl mu/V/e/sup -/ and noise of about...

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Summer 1992 Terminal area-Local Analysis and Prediction System (T-LAPS) evaluation

Published in:
MIT Lincoln Laboratory Report ATC-218

Summary

The Integrated Terminal Weather System (ITWS) is a development program initiated by the Federal Administration (FAA) to produce a fully automated, integrated terminal weather information system to improve the safety, efficiency and capacity of terminal area aviation operations. The ITWS will acquire data from FAA and National Weather Service sensors as well as from aircraft in flight in the terminal area. The ITWS will provide Air Traffic personnel with products that are immediately usable without further meteorological interpretation. Among the products are current terminal area weather, short-term (0-30 minute) predictions of significant weather phenomena, and the Terminal Winds product. The terminal winds product is the component of the ITWS which produces estimates of the horizontal winds on a three dimensional grid of points encompassing an airport terminal region. It uses information from a variety of sensors, including Doppler weather radars. In 1992, an operational test of an initial prototype Terminal Winds system was conducted at the MIT Lincoln Laboratory testbed in Orlando, FL. This report describes our evalution of the initial Terminal Winds prototype.
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Summary

The Integrated Terminal Weather System (ITWS) is a development program initiated by the Federal Administration (FAA) to produce a fully automated, integrated terminal weather information system to improve the safety, efficiency and capacity of terminal area aviation operations. The ITWS will acquire data from FAA and National Weather Service sensors...

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Mode S surveillance netting

Published in:
MIT Lincoln Laboratory Report ATC-120

Summary

The surveillance performance of a single Mode S Sensor is degraded by several factors, including: poor crossrange accuracy at long range, diffraction-induced azimuth errors, missing of incomplete reports, and extraneous reports. The surveillance netting project reported here sought to overcome these difficulties by employing information from a secondary (and perhaps also a tertiary) sensor. The project was performed to determine what auxiliary information is most useful, how this information could be used for maximum effect, when help should be sought from other sensors, what form this inter-sensor communication should take, and where the netting algorithms should be implemented. It was also planned to include the construction of a real-time netting demonstration system to exercise and test the concepts developed. The central issue in this project was the approach to be used for multi-sensor azimuth determination. In particular, a new form of incremental bilateration, employing a flat earth model, is shown to be both accurate and bias-resistant. Altitude estimation methods and multi-sensor tracker design are also addressed, with new algorithms developed in each case. Finally, the deisgn of the netting subsystem for a Mode S sensor is presented.
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Summary

The surveillance performance of a single Mode S Sensor is degraded by several factors, including: poor crossrange accuracy at long range, diffraction-induced azimuth errors, missing of incomplete reports, and extraneous reports. The surveillance netting project reported here sought to overcome these difficulties by employing information from a secondary (and perhaps...

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Mode S Beacon System: Functional Description (Revision B)

Published in:
MIT Lincoln Laboratory Report ATC-42,B

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 commucation 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 "DABS: A System Description", FAA-RD-74-189, November 1974 and "DABS: Functional Description," FAA-RD-80-41, April 1980.
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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...

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TCAS I design guidelines

Published in:
MIT Lincoln Laboratory Report ATC-114

Summary

A description of the FAA airborne Traffic Alert and Collision Avoidance System known as TCAS I introduces the main topic of the report: results of an investigation of simple techniques suitable for the passive and active detection of nearby aircraft by TCAS I. This is followed by a review of the measurement facilities and data used to evaluate the detection techniques. Techniques for identifying passively detected returns from potentially threatening aircraft, i.e., the rejection or "filtering out" of non-threat aircraft, are described and evaluated. Alternatives for time-sharing the 1090 MHz channel between the TCAS I transponder and the passive detector are described. A candidate passive detector is defined and its performance is evaluated using flight test data. Predictions of the performance of a low-power TCAS I based on active detection are made via link calculations and flight test measurements. A summary of results concludes the report.
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Summary

A description of the FAA airborne Traffic Alert and Collision Avoidance System known as TCAS I introduces the main topic of the report: results of an investigation of simple techniques suitable for the passive and active detection of nearby aircraft by TCAS I. This is followed by a review of...

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The Transportable Measurements Facility (TMF) system description

Published in:
MIT Lincoln Laboratory Report ATC-91
Topic:

Summary

This report describes the MIT Lincoln Laboratory Transportable Measurements Facility (TMF), a special purpose beacon interrogator patterned after the Discrete Address Beacon Sensor. This van-mounted experimental beacon system includes all ATCRBS/DABS reply processing and monopulse processing, but not other DABS processing. It was developed to collect data at various locations in the United States so that candidate DABS sensor antenna and processing could be evaluated in a real environment. The TMF has been installed and operated at: Logan Airport (Boston), Deer Island, MA (near Logan), Washington National Airport (DCA), Philadelphia Int. Airport (PHL), Clementon, NJ (near Philadelphia), Los Angeles Int. Airport (LAX), Brea, CA (25 miles east of LAX), Salt Lake City, UT (SLC), Layton, UT (near Salt Lake City), Las Vegas Airport (LAS), and Green Airport (Warwick, RI).
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Summary

This report describes the MIT Lincoln Laboratory Transportable Measurements Facility (TMF), a special purpose beacon interrogator patterned after the Discrete Address Beacon Sensor. This van-mounted experimental beacon system includes all ATCRBS/DABS reply processing and monopulse processing, but not other DABS processing. It was developed to collect data at various locations...

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DABS: Functional Description (Revision A)

Published in:
MIT Lincoln Laboratory Report ATC-42,A

Summary

This document provides a functional description of the Discrete Address Beacon System (DABS), 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. DABS is capable of common-channel interoperation with the current ATC beacon system, and may be implemented at low user cost over an extended ATCRBS-to-DABS transition period. In supporting ATC automation, DABS will provide the surveillance and communication performance required by the Automatic Traffic Advisory and Resolution Service (ATARS), 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 "DABS: A System Description", FAA-RD-74-189, November 1974.
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Summary

This document provides a functional description of the Discrete Address Beacon System (DABS), 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. DABS is capable of common-channel interoperation with the current...

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DABS installation and siting criteria

Published in:
MIT Lincoln Laboratory Report ATC-99

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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