Publications
Comparisons between the extended Kalman filter and the state-dependent Riccati estimator
Summary
Summary
The state-dependent Riccati equation-based estimator is becoming a popular estimation tool for nonlinear systems since it does not use system linearization. In this paper, the state-dependent Riccati equation-based estimator is compared with the widely used extended Kalman filter for three simple examples that appear in the open literature. It is...
Application of the Fornasini-Marchesini first model to data collected on a complex target model
Summary
Summary
This work describes the computation of scatterers that lay on the body of a real target which are depicted in radar images. A novelty of the approach is the target echoes collected by the radar are formulated into the first Fornasini-Marchesini (F-M) state space model to compute poles that give...
Unmanned aircraft sense and avoid radar: surrogate flight testing performance evaluation
Summary
Summary
Unmanned aircraft systems (UAS) have proven to have distinct advantages compared to manned aircraft for a variety of tasks. Current airspace regulations require a capability to sense and avoid other aircraft to replace the ability of a pilot to see and avoid other traffic. A prototype phased-array radar was developed...
LuminoCity: a 3D printed, illuminated city generated from LADAR data
Summary
Summary
In this work, we describe LuminoCity, a novel three-dimensional data display. A 3D printed model of Cambridge, MA was generated from LADAR data. A translucent plastic model was then cast from a mold of the 3D printed model. We developed a display system to project data onto the translucent model...
Transactional array reconciliation tomography for precision indoor location
Summary
Summary
A novel system is described for precision indoor location and tracking of personnel inside a building using RF signals exchanged with reference units deployed outside the building without benefit of infrastructure or site survey. Localization in high multipath without multilateration by fusion of unidirectional signals using singular array reconciliation tomography...
Multi-lithic phased array architecture for airborne sense and avoid radar
Summary
Summary
Transmit and receive Ku-band phased array designs are described for testing an airborne sense and avoid radar. The arrays are small with a size of 24 cm x 9 cm and operate from 13 to 17 GHz with electronic scanning from plus of minus 45 degrees in azimuth and plus...
Geospatial analysis based on GIS integrated with LADAR
Summary
Summary
In this work, we describe multi-layered analyses of a high-resolution broad-area LADAR data set in support of expeditionary activities. High-level features are extracted from the LADAR data, such as the presence and location of buildings and cars, and then these features are used to populate a GIS (geographic information system)...
Stepped notch antenna array used as a low thermal resistance heat sink
Summary
Summary
A stepped notch antenna at Ku-band is developed to provide a thermal heat sink for active arrays. The antenna with forced air cooling provides up to 0.4 degrees C/W of thermal resistance. The antenna integration with a printed circuit board allows for high volume surface mount assembly of active devices.
The directivity of a Yagi-Uda antenna from an effective propagation constant
Summary
Summary
A technique is presented for determining the directivity of a long, uniform Yagi-Uda antenna. It is shown that the maximum directivity is limited by the propagation constant of the particular antenna structure. The propagation constant can be determined by means of a two-part antenna test fixture with M and M...
Dwell scheduling algorithms for phased array antenna
Summary
Summary
In a multifunctional radar performing searching and tracking operations, the maximum number of targets that can be managed is an important measure of performance. One way a radar can maximize tracking performance is to optimize its dwell scheduling. The problem of designing efficient dwell scheduling algorithms for various tracking and...