Publications
Three-dimensional integration technology for advanced focal planes
Summary
Summary
We have developed a three-dimensional (3D) circuit integration technology that exploits the advantages of silicon-on-insulator (SOI) technology to enable wafer-level stacking and micrometer-scale electrical interconnection of fully fabricated circuit wafers. This paper describes the 3D technology and discusses some of the advanced focal plane arrays that have been built using...
The MIT-LL/AFRL IWSLT-2008 MT System
Summary
Summary
This paper describes the MIT-LL/AFRL statistical MT system and the improvements that were developed during the IWSLT 2008 evaluation campaign. As part of these efforts, we experimented with a number of extensions to the standard phrase-based model that improve performance for both text and speech-based translation on Chinese and Arabic...
Time delay integration and in-pixel spatiotemporal filtering using a nanoscale digital CMOS focal plane readout
Summary
Summary
A digital focal plane array (DFPA) architecture has been developed that incorporates per-pixel full-dynamic-range analog-to-digital conversion and orthogonal-transfer-based realtime digital signal processing capability. Several long-wave infrared-optimized pixel processing focal plane readout integrated circuit (ROIC) designs have been implemented, each accommodating a 256 x 256 30-um-pitch detector array. Demonstrated in this...
A multi-sensor compressed sensing receiver: performance bounds and simulated results
Summary
Summary
Multi-sensor receivers are commonly tasked with detecting, demodulating and geolocating target emitters over very wide frequency bands. Compressed sensing can be applied to persistently monitor a wide bandwidth, given that the received signal can be represented using a small number of coefficients in some basis. In this paper we present...
Rapid prototyping of radar algorithms
Summary
Summary
Rapid prototyping of advanced signal processing algorithms is critical to developing new radars. Signal processing engineers usually use high level languages like MATLAB, IDL, or Python to develop advanced algorithms and to determine the optimal parameters for these algorithms. Many of these algorithms have very long execution times due to...
CompositeMatch: detecting n-ary matches in ontology alignment
Summary
Summary
The field of ontology alignment still contains numerous unresolved problems, one of which is the accurate identification of composite matches. In this work, we present a context-sensitive ontology alignment algorithm, CompositeMatch, that identifies these matches, along with the typical one-to-one matches, by looking more broadly at the information that a...
TCAS multiple threat encounter analysis
Summary
Summary
The recent development of high-fidelity U.S. airspace encounter models at Lincoln Laboratory has motivated a simulation study of the Traffic Alert and Collision Avoidance System (TCAS) multiple threat logic. We observed from archived radar data that while rarer than single-threat encounters, multiple threat encounters occur more frequently than originally expected...
Sinewave parameter estimation using the fast Fan-Chirp Transform
Summary
Summary
Sinewave analysis/synthesis has long been an important tool for audio analysis, modification and synthesis [1]. The recently introduced Fan-Chirp Transform (FChT) [2,3] has been shown to improve the fidelity of sinewave parameter estimates for a harmonic audio signal with rapid frequency modulation [4]. A fast version of the FChT [3]...
Towards co-channel speaker separation by 2-D demodulation of spectrograms
Summary
Summary
This paper explores a two-dimensional (2-D) processing approach for co-channel speaker separation of voiced speech. We analyze localized time-frequency regions of a narrowband spectrogram using 2-D Fourier transforms and propose a 2-D amplitude modulation model based on pitch information for single and multi-speaker content in each region. Our model maps...
Moving clutter spectral filter for Terminal Doppler Weather Radar
Summary
Summary
Detecting low-altitude wind shear in support of aviation safety and efficiency is the primary mission of the Terminal Doppler Weather Radar (TDWR). The wind-shear detection performance depends directly on the quality of the data produced by the TDWR. At times the data quality suffers from the presence of clutter. Al-though...