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Discovering the smallest observed near-earth objects with the space surveillance telescope

February 26, 2019
  |
Journal Article
Author:
Arthur Lue
…
Published in:
Icarus, Vol. 325, 2019, pp. 105-114.
Topic:
asteroids
R&D area:
R&D group:

Summary

The Space Surveillance Telescope (SST) is an advanced optical sensor designed and tested by MIT Lincoln Laboratory for the Defense Advanced Research Projects Agency (DARPA), which is currently in the process of being integrated into the Space Surveillance Network. By operating the telescope in a manner normally intended for the discovery of small, artificial space objects, SST is serendipitously sensitive to the detection of very small asteroids as they traverse close to the Earth, passing rapidly through SST's search volume. This mode of operation stands in contrast to the standard approach for the search and discovery of asteroids and near-Earth objects (NEOs), in which longer revisit times restrict survey sensitivities to objects moving no faster than about 20 degrees/day. From data collected during SST's observation runs in New Mexico, we detail the discovery of 92 new candidate objects in heliocentric orbit whose absolute magnitudes range from H=26.4 to 35.9 (approximately 18-m to 25-cm in size). Some of these discoveries represent the smallest natural objects ever observed in orbit. We compare the candidate objects with bolide observations.
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Summary

The Space Surveillance Telescope (SST) is an advanced optical sensor designed and tested by MIT Lincoln Laboratory for the Defense Advanced Research Projects Agency (DARPA), which is currently in the process of being integrated into the Space Surveillance Network. By operating the telescope in a manner normally intended for the...

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Discovering the smallest observed near-earth objects with the space surveillance telescope

Command and control for multifunction phased array radar

October 1, 2017
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Journal Article
Author:
Mark E. Weber
…
Published in:
IEEE Trans. Geosci. Remote Sens., Vol. 55, No. 10, October 2017, pp. 5899-5912.
Topic:
algorithms
R&D area:
R&D group:

Summary

We discuss the challenge of managing the Multifunction Phased Array Radar (MPAR) timeline to satisfy the requirements of its multiple missions, with a particular focus on weather surveillance. This command and control (C2) function partitions the available scan time among these missions, exploits opportunities to service multiple missions simultaneously, and utilizes techniques for increasing scan rate where feasible. After reviewing the candidate MPAR architectures and relevant previous research, we describe a specific C2 framework that is consistent with a demonstrated active array architecture using overlapped subarrays to realize multiple, concurrent receive beams. Analysis of recently articulated requirements for near-airport and national-scale aircraft surveillance indicates that with this architecture, 40–60% of the MPAR scan timeline would be available for the high-fidelity weather observations currently provided by the Weather Service Radar (WSR-88D) network. We show that an appropriate use of subarray generated concurrent receive beams, in concert with previously documented, complementary techniques to increase the weather scan rate, could enable MPAR to perform full weather volume scans at a rate of 1 per minute. Published observing system simulation experiments, human-in-the-loop studies and radar-data assimilation experiments indicate that high-quality weather radar observations at this rate may significantly improve the lead time and reliability of severe weather warnings relative to current observation capabilities.
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Summary

We discuss the challenge of managing the Multifunction Phased Array Radar (MPAR) timeline to satisfy the requirements of its multiple missions, with a particular focus on weather surveillance. This command and control (C2) function partitions the available scan time among these missions, exploits opportunities to service multiple missions simultaneously, and...

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Command and control for multifunction phased array radar

Secondary Surveillance Phased Array Radar (SSPAR): initial feasibility study

February 6, 2014
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Project Report
Author:
Mark E. Weber
…
Published in:
MIT Lincoln Laboratory Report ATC-416
Topic:
radar
R&D area:
R&D group:

Summary

The U.S. Federal Aviation Administration is deploying Automatic Dependent Surveillance-Broadcast (ADS-B) to provide next-generation surveillance derived through down- and cross-link of global positioning satellite (GPS) navigation data. While ADS-B will be the primary future surveillance system, FAA recognizes that backup surveillance capabilities must be provided to assure that air traffic control (ATC) services can continue to be provided when individual aircraft transponders fail and during localized, short-duration GPS outages. This report describes a potential ADS-B backup capability, Secondary Surveillance Phased Array Radar or SSPAR. SSPAR will interrogate aircraft transponders and receive replies using a sparse, non-rotating array of approximately 17 omnidirectional (in azimuth) antennae. Each array element will transmit and receive independently so as to form directional transmit beams for transponder interrogation, and support high-resolution direction finding for received signals. Because each SSPAR element is independently digitized, transponder returns from all azimuths can be equipped with Traffic Alert and Collision Avoidance System (TCAS) and ADS-B avionics to reduce spectrum usage and maintain the high surveillance update rate (~1 per second) achieved by ADS-B. Recurring costs for SSPAR will be low since it involves no moving parts and the number of array channels is small. This report describes an SSPAR configuration supporting terminal operations. We consider interrogation and receive approaches, antenna array configuration, signal processing and preliminary performance analysis. An analysis of SSPAR's impact on spectrum congestion in the beacon radar band is presented, as are concepts for integrating SSPAR and next generation primary radar to improve the efficiency and accuracy of aircraft and weather surveillance.
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Summary

The U.S. Federal Aviation Administration is deploying Automatic Dependent Surveillance-Broadcast (ADS-B) to provide next-generation surveillance derived through down- and cross-link of global positioning satellite (GPS) navigation data. While ADS-B will be the primary future surveillance system, FAA recognizes that backup surveillance capabilities must be provided to assure that air traffic...

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Secondary Surveillance Phased Array Radar (SSPAR): initial feasibility study

Multifunction Phased Array Radar (MPAR): achieving Next Generation Surveillance and Weather Radar Capability

September 1, 2013
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Journal Article
Author:
Mark E. Weber
…
Published in:
J. Air Traffic Control, Vol. 55, No. 3, Fall 2013, pp. 40-7.
Topic:
radar
R&D area:
R&D group:

Summary

Within DOT, the FAA has initiated an effort known as the NextGen Surveillance and Weather Radar Capability (NSWRC) to analyze the need for the next generation radar replacement and assess viable implementation alternatives. One concept under analysis is multifunction radar using phased-array technology -- Multifunction Phased Array Radar or MPAR.
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Summary

Within DOT, the FAA has initiated an effort known as the NextGen Surveillance and Weather Radar Capability (NSWRC) to analyze the need for the next generation radar replacement and assess viable implementation alternatives. One concept under analysis is multifunction radar using phased-array technology -- Multifunction Phased Array Radar or MPAR.

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Multifunction Phased Array Radar (MPAR): achieving Next Generation Surveillance and Weather Radar Capability

An assessment of the operational utility of a GOES lightning mapping sensor

May 28, 2013
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Project Report
Author:
Mark E. Weber
…
Published in:
MIT Lincoln Laboratory Report NOAA-18A
Topic:
surveillance
R&D area:
R&D group:

Summary

This report evaluates the incremental operational benefits of a proposed Lightning Mapping Sensor (LMS) for NOAA's Geostationary Operational Environmental Satellites (GOES). If deployed, LMS would provide continuous, real-time surveillance of total lightning activity over large portions of the North and South American continents and surrounding oceans. In contrast to the current National Lightning Detection Network, LMS would monitor total lightning activity, including the dominant intracloud component which is estimated to occur with order of magnitude greater frequency than cloud-to-ground lightning and may occur ten minutes or more in advance of a storm's first ground flash.
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Summary

This report evaluates the incremental operational benefits of a proposed Lightning Mapping Sensor (LMS) for NOAA's Geostationary Operational Environmental Satellites (GOES). If deployed, LMS would provide continuous, real-time surveillance of total lightning activity over large portions of the North and South American continents and surrounding oceans. In contrast to the...

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An assessment of the operational utility of a GOES lightning mapping sensor

Triangle TCAS antenna

March 31, 2011
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Project Report
Author:
William H. Harman III
…
Published in:
MIT Lincoln Laboratory Report ATC-380
Topic:
surveillance
R&D area:
R&D group:

Summary

The Traffic Alert and Collision Avoidance (TCAS) provides a pilot display showing the range and bearing of nearby aircraft. TCAS obtains the bearing information by using an angle-of-arrival antenna. In the development of TCAS at Lincoln Laboratory, the first airborne tests were conducted using an Adcock antenna, which is a small square array of four monopole elements. This report describes an alternative antenna for TCAS, using three elements in the shape of a triangle. It is shown that the triangle antenna is less sensitive to receiver noise, and that improvement factor is about 10 dB.
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Summary

The Traffic Alert and Collision Avoidance (TCAS) provides a pilot display showing the range and bearing of nearby aircraft. TCAS obtains the bearing information by using an angle-of-arrival antenna. In the development of TCAS at Lincoln Laboratory, the first airborne tests were conducted using an Adcock antenna, which is a...

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Triangle TCAS antenna

Progress of Multifunction Phased Array Radar (MPAR) program

January 14, 2009
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Conference Paper
Author:
William E. Benner
…
Published in:
89th AMS Annual Conf., 11-15 January 2009.
Topic:
aviation weather
R&D area:
R&D group:

Summary

This paper will discuss the progress the Multi-function Phased Array Radar (MPAR) research program has made over the last 18 months as well as insight into the program strategy for moving forward. Current research activities include evaluating the impact of MPAR's faster scanning rates to aviation weather algorithms (e.g., how it will help in predicting storm growth and decay) and exploring dual polarization for phased array radars. Additionally, the Department of Homeland Security (DHS) has expanded the MPAR multi-agency partnership and is sponsoring research into the mitigation of wind-farm interference on weather sensing. Significant research in semi-conductor technology and advances in transmit/receive module design and phased array architectures are beginning to create a pathway towards system affordability. The MPAR program plan calls for a technology demonstration phase followed by the initiation of a prototype development effort within the next five years. This paper will provide the updates on these and other program activities.
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Summary

This paper will discuss the progress the Multi-function Phased Array Radar (MPAR) research program has made over the last 18 months as well as insight into the program strategy for moving forward. Current research activities include evaluating the impact of MPAR's faster scanning rates to aviation weather algorithms (e.g., how...

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Progress of Multifunction Phased Array Radar (MPAR) program

Automatic dependent surveillance-broadcast in the Gulf of Mexico

December 1, 2008
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Journal Article
Author:
Steven D. Thompson
…
Published in:
Lincoln Laboratory Journal, Vol. 17, No. 2, December 2008, pp. 55-69.
Topic:
air traffic control
R&D area:
R&D group:

Summary

The Federal Aviation Administration is adopting Automatic Dependent Surveillance-Broadcast (ADS-B) to provide surveillance in the National Airspace System (NAS). Aircraft separation services are currently provided by a system of en route and terminal radars, and the performance of these radars in part dictates the separation distance required between aircraft. ADS-B is designed to provide comparable service in areas where no radar coverage exists. It will eventually be the primary surveillance source in the NAS, if it is proven to provide performance equal to or better than radar.
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Summary

The Federal Aviation Administration is adopting Automatic Dependent Surveillance-Broadcast (ADS-B) to provide surveillance in the National Airspace System (NAS). Aircraft separation services are currently provided by a system of en route and terminal radars, and the performance of these radars in part dictates the separation distance required between aircraft. ADS-B...

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Automatic dependent surveillance-broadcast in the Gulf of Mexico

Detection probability modeling for airport wind-shear sensors

September 15, 2008
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Project Report
Author:
John Y. Cho
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Published in:
MIT Lincoln Laboratory Report ATC-340
Topic:
wind shear
R&D area:
R&D group:

Summary

An objective wind-shear detection probability estimation model is developed for radar, lidar, and sensor combinations. The model includes effects of system sensitivity, site-specific wind-shear, clutter, and terrain blockage characteristics, range-aliased obscuration statistics, antenna beam filling and attenuation, and signal processing differences which allow a sensor- and site-specific performance analysis of deployed and future systems. A total of 161 sites are analyzed for the study, consisting of airports currently serviced by the Terminal Doppler Weather Radar (TDWR) (46), Airport Surveillance Radar Weather Systems Processor (ASR-9 WSP) (35), Low Altitude Wind Shear Alert System-Relocation/Sustainment (LLWAS-RS) (40), and no wind-shear detection system (40). Sensors considered are the TDWR, WSP, LLWAS, Weather Surveillance Radar 1988-Doppler (WSR-88D, commonly known as NEXRAD), adn the Lockheed Martin Coherent Technologies (LMCT) Doppler lidar and proposed x-band radar. [not complete]
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Summary

An objective wind-shear detection probability estimation model is developed for radar, lidar, and sensor combinations. The model includes effects of system sensitivity, site-specific wind-shear, clutter, and terrain blockage characteristics, range-aliased obscuration statistics, antenna beam filling and attenuation, and signal processing differences which allow a sensor- and site-specific performance analysis of...

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Detection probability modeling for airport wind-shear sensors

Elementary surveillance (ELS) and enhanced surveillance (EHS) validation via Mode S secondary radar surveillance

April 25, 2008
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Project Report
Author:
Robert D. Grappel
…
Published in:
MIT Lincoln Laboratory Report ATC-337
Topic:
surveillance
R&D area:
R&D group:

Summary

Several applications of the Mode S data link are currently being implemented and equipage requirements have been issued in countries around the world. Elementary surveillance (ELS) and enhanced surveillance (EHS) applications have been mandated in Europe with full equipage of all aircraft in the airspace required by 2009. Exemptions to the ELS requirement include aircraft that will be out of service by 31 December 2009, and aircraft undergoing flight-testing, delivery, or transit into or out of maintenance bases. Transport type aircraft (defined as having a maximum take-off weight in excess of 250 knots) are to be equipped to support ELS and EHS. Exemptions to the requirements for EHS include those listed above for ELS and: a- fighter and training aircraft; b- rotary-wing aircraft; c- existing/older transport type aircraft undergoing avionics upgrades which will then support ELS/EHS; and d- aircraft types granted special exemptions (e.g., B1-B, B2-A, and B-52H bombers). [not complete]
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Summary

Several applications of the Mode S data link are currently being implemented and equipage requirements have been issued in countries around the world. Elementary surveillance (ELS) and enhanced surveillance (EHS) applications have been mandated in Europe with full equipage of all aircraft in the airspace required by 2009. Exemptions to...

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Elementary surveillance (ELS) and enhanced surveillance (EHS) validation via Mode S secondary radar surveillance
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