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Dallas/Fort Worth field demonstration #2 (DFW-2) final report for Tower Flight Data Manager (TFDM)

May 16, 2012
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Project Report
Author:
Hayley J. Reynolds
…
Published in:
MIT Lincoln Laboratory Report ATC-393
Topic:
air traffic control
R&D area:

Summary

The Tower Flight Data Manager (TFDM) is the next generation air traffic control tower (ATCT) information system that integrates surveillance, flight data, and other sources, which enables advanced decision support tools (DSTs) to improve departure and arrival efficiency and reduce fuel burn at the airport. TFDM was exercised as a prototype installed at the Dallas / Fort Worth International Airport (DFW) during a two-week demonstration in the spring of 2011 termed DFW-2. MIT Lincoln Laboratory conducted this demonstration for the FAA in coordination with DFW air traffic control (ATC) and the DFW airport authority. The objective of this TFDM field demonstration was to validate the operational suitability and refine production system requirements of the Tower Information Display System (TIDS) surface surveillance display and Flight Data Manager (FDM) electronic flight data display and to evaluate the first iteration of the Supervisor Display and DSTs. These objectives were met during the two-week field demonstration. Results indicated that the TIDS and FDM exhibited capabilities considered operationally suitable for the tower as an advisory system and as a primary means for control given surface surveillance that is approved for operational use. Human factors data indicated that TIDS and FDM could be beneficial. The prototype Supervisor Display and DSTs met a majority of the technical performance criteria, but fewer than half of the human factors success criteria were met. As this was the first iteration of the Supervisor Display and DST capabilities, subsequent prototype iterations to achieve the target concept of operations, functionality and information presentation with accompanying field demonstrations to evaluate these honed capabilities were recommended and expected. FLM/TMC feedback will help refine subsequent system design.
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Summary

The Tower Flight Data Manager (TFDM) is the next generation air traffic control tower (ATCT) information system that integrates surveillance, flight data, and other sources, which enables advanced decision support tools (DSTs) to improve departure and arrival efficiency and reduce fuel burn at the airport. TFDM was exercised as a...

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Dallas/Fort Worth field demonstration #2 (DFW-2) final report for Tower Flight Data Manager (TFDM)

Vertically stacked RF switches by wafer-scale three-dimensional integration

May 10, 2012
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Journal Article
Author:
Chang-Lee Chen
…
Published in:
Electron. Lett., Vol. 48, No. 10, 10 May 2012.
Topic:
integrated circuit
R&D area:

Summary

Vertically stacked RF switches implemented by wafer-scale three-dimensional (3D) integration of three completely fabricated silicon-on-insulator wafers are demonstrated. The individual switch performance was maintained through the 3D integration process while the signal path is shortened by vertical interconnects. The footprint of the switch can be shrunk in proportion to the number of tiers it is distributed between, demonstrating the potential of significant size reduction of multiple-throw switches commonly required in many applications.
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Summary

Vertically stacked RF switches implemented by wafer-scale three-dimensional (3D) integration of three completely fabricated silicon-on-insulator wafers are demonstrated. The individual switch performance was maintained through the 3D integration process while the signal path is shortened by vertical interconnects. The footprint of the switch can be shrunk in proportion to the...

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Vertically stacked RF switches by wafer-scale three-dimensional integration

The MIT IAP radar course: build a small radar system capable of sensing range, Doppler, and synthetic aperture (SAR) imaging

May 7, 2012
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Conference Paper
Author:
Gregory L. Charvat
…
Published in:
Proc. of the 2012 IEEE Radar Conf., 7-11 May 2012.
Topic:
doppler radar
R&D area:
R&D group:

Summary

MIT Lincoln Laboratory sponsored a radar short course at MIT campus during the January 2011 Independent Activities Period (IAP). The objective of this course was to generate student interest in applied electromagnetics, antennas, radio frequency (RF) electronics, analog circuits, and signal processing by building a short-range radar sensor and using it in a series of field tests. Lectures on the fundamentals of radar, modular RF design, antennas, pulse compression and synthetic aperture radar (SAR) imaging were presented. Teams of three students built a radar system from a kit. This kit was developed by the authors and uses a frequency modulated continuous wave (FMCW) architecture. To save costs, empty metal coffee cans are used for antennas, components are mounted on a wood block, the system uses only six coaxial microwave parts, analog circuitry on a solderless breadboard, and runs on eight AA batteries. Analog data is acquired by the audio input port on a laptop computer. The total cost of each kit was $360 which made this radar technology accessible to students. Of the nine student groups, all succeeded in building their radar, acquiring Doppler vs. time and range vs. time plots, seven succeeded in acquiring SAR imagery, and some groups improved the radar system. By presenting these difficult topics at a high level while at the same time making a radar kit and performing field experiments, students became self motivated to explore these topics and much interest in radar design was generated.
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Summary

MIT Lincoln Laboratory sponsored a radar short course at MIT campus during the January 2011 Independent Activities Period (IAP). The objective of this course was to generate student interest in applied electromagnetics, antennas, radio frequency (RF) electronics, analog circuits, and signal processing by building a short-range radar sensor and using...

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The MIT IAP radar course: build a small radar system capable of sensing range, Doppler, and synthetic aperture (SAR) imaging

Evaluation of the Integrated Departure Route Planning (IDRP) Tool 2011 prototype

May 3, 2012
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Project Report
Author:
Richard A. DeLaura
…
Published in:
MIT Lincoln Laboratory Report ATC-388
Topic:
decision support
R&D area:
R&D group:

Summary

The Integrated Departure Route Planning (IDRP) tool combines convective weather impact forecasts from the Route Availability Planning Tool (RAPT) with departure demand forecasts from the MITRE tfmCore system to aid traffic managers in formulating plans to mitigate volume congestion in fair weather and during convective weather impacts. An initial prototype was deployed in the summer of 2010 for a very limited field evaluation. A second, more comprehensive field evaluation of the "Phase 2" IDRP prototype was performed in the summer of 2011. The key focus of IDRP is the planning and implementation of departure reroutes to avoid weather impacts and volume congestion on departure fixes and routes. This evaluation assesses three facets of the IDRP prototype critical to the successful realization of its concept of operations: 1. performance of weather impact forecasts from RAPT and departure demand forecasts from tfmCore, 2. effectiveness of reroute decisions, and 3. potential impacts on procedures and decision making based on observations of IDRP use in the field. The evaluation concludes with suggestions for future enhancements to improve the performance and realization of potential benefits in operational use of IDRP.
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Summary

The Integrated Departure Route Planning (IDRP) tool combines convective weather impact forecasts from the Route Availability Planning Tool (RAPT) with departure demand forecasts from the MITRE tfmCore system to aid traffic managers in formulating plans to mitigate volume congestion in fair weather and during convective weather impacts. An initial prototype...

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Evaluation of the Integrated Departure Route Planning (IDRP) Tool 2011 prototype

Driven dynamics and rotary echo of a qubit tunably coupled to a harmonic oscillator

April 27, 2012
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Journal Article
Author:
Simon Gustavsson
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Published in:
Phys. Rev. Lett., Vol. 108, No. 17, 27 April 2012, 170503.
Topic:
quantum
R&D area:
R&D group:

Summary

We have investigated the driven dynamics of a superconducting flux qubit that is tunably coupled to a microwave resonator. We find that the qubit experiences an oscillating field mediated by off-resonant driving of the resonator, leading to strong modifications of the qubit Rabi frequency. This opens an additional noise channel, and we find that low-frequency noise in the coupling parameter causes a reduction of the coherence time during driven evolution. The noise can be mitigated with the rotary-echo pulse sequence, which, for driven systems, is analogous to the Hahn-echo sequence.
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Summary

We have investigated the driven dynamics of a superconducting flux qubit that is tunably coupled to a microwave resonator. We find that the qubit experiences an oscillating field mediated by off-resonant driving of the resonator, leading to strong modifications of the qubit Rabi frequency. This opens an additional noise channel...

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Driven dynamics and rotary echo of a qubit tunably coupled to a harmonic oscillator

Readout circuitry for continuous high-rate photon detection with arrays of InP Geiger-mode avalanche photodiodes

April 23, 2012
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Conference Paper
Author:
Jonathan P. Frechette
…
Published in:
SPIE, Vol. 8375, Advanced Photon Counting Techniques VI, 23 April 2012, 83750W.
Topic:
integrated circuit
R&D area:

Summary

An asynchronous readout integrated circuit (ROIC) has been developed for hybridization to a 32x32 array of single-photon sensitive avalanche photodiodes (APDs). The asynchronous ROIC is capable of simultaneous detection and readout of photon times of arrival, with no array blind time. Each pixel in the array is independently operated by a finite state machine that actively quenches an APD upon a photon detection event, and re-biases the device into Geiger mode after a programmable hold-off time. While an individual APD is in hold-off mode, other elements in the array are biased and available to detect photons. This approach enables high pixel refresh frequency (PRF), making the device suitable for applications including optical communications and frequency-agile ladar. A built-in electronic shutter that de-biases the whole array allows the detector to operate in a gated mode or allows for detection to be temporarily disabled. On-chip data reduction reduces the high bandwidth requirements of simultaneous detection and readout. Additional features include programmable single-pixel disable, region of interest processing, and programmable output data rates. State-based on-chip clock gating reduces overall power draw. ROIC operation has been demonstrated with hybridized InP APDs sensitive to 1.06-Mm and 1.55-Mm wavelength, and fully packaged focal plane arrays (FPAs) have been assembled and characterized.
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Summary

An asynchronous readout integrated circuit (ROIC) has been developed for hybridization to a 32x32 array of single-photon sensitive avalanche photodiodes (APDs). The asynchronous ROIC is capable of simultaneous detection and readout of photon times of arrival, with no array blind time. Each pixel in the array is independently operated by...

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Readout circuitry for continuous high-rate photon detection with arrays of InP Geiger-mode avalanche photodiodes

Next-generation airborne collision avoidance system

April 11, 2012
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Journal Article
Author:
Mykel J. Kochenderfer
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Published in:
Lincoln Laboratory Journal, Vol. 19, No. 1, 2012, pp. 17-33.
Topic:
collision avoidance
R&D area:
R&D group:

Summary

In response to a series of midair collisions involving commercial airliners, Lincoln Laboratory was directed by the Federal Aviation Administration in the 1970s to participate in the development of an onboard collision avoidance system. In its current manifestation, the Traffic Alert and Collision Avoidance System is mandated worldwide on all large aircraft and has significantly improved the safety of air travel, but major changes to the airspace planned over the coming years will require substantial modification to the system. Recently, Lincoln Laboratory has been pioneering the development of a new approach to collision avoidance systems that completely rethinks how such systems are engineered, allowing the system to provide a higher degree of safety without interfering with normal, safe operations.
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Summary

In response to a series of midair collisions involving commercial airliners, Lincoln Laboratory was directed by the Federal Aviation Administration in the 1970s to participate in the development of an onboard collision avoidance system. In its current manifestation, the Traffic Alert and Collision Avoidance System is mandated worldwide on all...

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Next-generation airborne collision avoidance system

External cavity beam combining of 21 semiconductor lasers using SPGD

April 10, 2012
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Journal Article
Author:
Juan C. Montoya
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Published in:
Appl. Opt., Vol. 51, No. 11, 10 April 2012, pp. 1724-1728.
Topic:
lasers
R&D area:
R&D group:

Summary

Active coherent beam combining of laser oscillators is an attractive way to achieve high output power in a diffraction limited beam. Here we describe an active beam combining system used to coherently combine 21 semiconductor laser elements with an 81% beam combining efficiency in an external cavity configuration compared with an upper limit of 90% efficiency in the particular configuration of the experiment. Our beam combining system utilizes a stochastic parallel gradient descent (SPGD) algorithm for active phase control. This work demonstrates that active beam combining is not subject to the scaling limits imposed on passive-phasing systems.
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Summary

Active coherent beam combining of laser oscillators is an attractive way to achieve high output power in a diffraction limited beam. Here we describe an active beam combining system used to coherently combine 21 semiconductor laser elements with an 81% beam combining efficiency in an external cavity configuration compared with...

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External cavity beam combining of 21 semiconductor lasers using SPGD

FY11 Line-Supported Bio-Next Program - Multi-modal Early Detection Interactive Classifier (MEDIC) for mild traumatic brain injury (mTBI) triage

April 9, 2012
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Project Report
Author:
Laurel R. Keyes
…
Published in:
MIT Lincoln Laboratory Report LSP-34
Topic:
biology
R&D area:
R&D group:

Summary

The Multi-modal Early Detection Interactive Classifier (MEDIC) is a triage system designed to enable rapid assessment of mild traumatic brain injury (mTBI) when access to expert diagnosis is limited as in a battlefield setting. MEDIC is based on supervised classification that requires three fundamental components to function correctly; these are data, features, and truth. The MEDIC system can act as a data collection device in addition to being an assessment tool. Therefore, it enables a solution to one of the fundamental challenges in understanding mTBI: the lack of useful data. The vision of MEDIC is to fuse results from stimulus tests in each of four modalitites - auditory, occular, vocal, and intracranial pressure - and provide them to a classifier. With appropriate data for training, the MEDIC classifier is expected to provide an immediate decision of whether the subject has a strong likelihood of having sustained an mTBI and therefore requires an expert diagnosis from a neurologist. The tests within each modalitity were designed to balance the capacity of objective assessment and the maturity of the underlying technology against the ability to distinguish injured from non-injured subjects according to published results. Selection of existing modalities and underlying features represents the best available, low cost, portable technology with a reasonable chance of success.
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Summary

The Multi-modal Early Detection Interactive Classifier (MEDIC) is a triage system designed to enable rapid assessment of mild traumatic brain injury (mTBI) when access to expert diagnosis is limited as in a battlefield setting. MEDIC is based on supervised classification that requires three fundamental components to function correctly; these are...

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FY11 Line-Supported Bio-Next Program - Multi-modal Early Detection Interactive Classifier (MEDIC) for mild traumatic brain injury (mTBI) triage

A scalable signal processing architecture for massive graph analysis

March 25, 2012
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Conference Paper
Author:
Benjamin A. Miller
…
Published in:
ICASSP 2012, Proc. IEEE Int. Conf. on Acoustics, Speech and Signal Processing, 25-30 March 2012, pp. 5329-32.
Topic:
supercomputing
R&D area:
R&D group:

Summary

In many applications, it is convenient to represent data as a graph, and often these datasets will be quite large. This paper presents an architecture for analyzing massive graphs, with a focus on signal processing applications such as modeling, filtering, and signal detection. We describe the architecture, which covers the entire processing chain, from data storage to graph construction to graph analysis and subgraph detection. The data are stored in a new format that allows easy extraction of graphs representing any relationship existing in the data. The principal analysis algorithm is the partial eigendecomposition of the modularity matrix, whose running time is discussed. A large document dataset is analyzed, and we present subgraphs that stand out in the principal eigenspace of the time varying graphs, including behavior we regard as clutter as well as small, tightly-connected clusters that emerge over time.
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Summary

In many applications, it is convenient to represent data as a graph, and often these datasets will be quite large. This paper presents an architecture for analyzing massive graphs, with a focus on signal processing applications such as modeling, filtering, and signal detection. We describe the architecture, which covers the...

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A scalable signal processing architecture for massive graph analysis
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