Institution
Raytheon
Company•Waltham, Massachusetts, United States•
About: Raytheon is a company organization based out in Waltham, Massachusetts, United States. It is known for research contribution in the topics: Signal & Antenna (radio). The organization has 15290 authors who have published 18973 publications receiving 300052 citations.
Topics: Signal, Antenna (radio), Radar, Turbine, Amplifier
Papers published on a yearly basis
Papers
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16 Aug 2001TL;DR: In this paper, a radar detection process includes computing a derivative of an FFT output signal to detect an object within a specified detection zone, where the range of the object is determined as a function of the frequency at which the zero crossing occurs.
Abstract: A radar detection process includes computing a derivative of an FFT output signal to detect an object within a specified detection zone. In one embodiment, a zero crossing in the second derivative of the FFT output signal indicates the presence of an object. The range of the object is determined as a function of the frequency at which the zero crossing occurs. Also described is a detection table containing indicators of the presence or absence of an object within a respective radar beam and processing cycle. At least two such indicators are combined in order to detect the presence of an object within the detection zone and with changing range gates in each of the antenna beams the coverage of the detection zone can be varied.
68 citations
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02 Dec 2002TL;DR: In this article, an active set algorithm is proposed to solve the convex quadratic program with inequality constraints in real-time. But the algorithm is not suitable for the case where the physical limitations of the system translate to optimal active sets.
Abstract: Real-time control of a dynamical system is provided by determining control variables that get as close as possible to producing a desired response. Additional consideration of physical limitations leads to a convex Quadratic Program with inequality constraints that needs to be solved in real-time. A new active set algorithm is described to solve the convex Quadratic Program efficiently that meets real-time requirements. Based on the key observation that the physical limitations of the system translate to optimal active sets that remain relatively unchanged over time (even though the actual optimal controls may be varying), starting guesses for the active set obtained from the final iterate in the previous time period greatly reduces the number of iterations and hence allows the Quadratic Programs to be solved to convergence in real-time.
68 citations
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01 Apr 1977TL;DR: A position and force measuring system for determining the coordinates and force applied to a point on a rigid plate or surface fixed to a rigid foundation by means of a flexible support mechanism and at least three spaced apart sensors is described in this paper.
Abstract: A position and force measuring system for determining the coordinates and force applied to a point on a rigid plate or surface fixed to a rigid foundation by means of a flexible support mechanism and at least three spaced apart sensors. The sensors each deliver an output signal which is proportional to the applied force and the coordinates of the force. The output signals are fed into a processor which computes the force and the coordinates at which the force is applied.
68 citations
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30 Jul 1970TL;DR: In this article, a dual frequency ranging and communication system for communicating with and locating mobile vehicles in a multipath environment such as an urban center is proposed, where a plurality of remote relay stations are located at points throughout the urban area, each station receiving and transmitting coded digital data and tone signals, the tone signals being used for phase ranging.
Abstract: A dual frequency ranging and communication system for communicating with and locating mobile vehicles in a multipath environment such as an urban center. This system functions in urban areas for both communication and ranging where line of sight radiation techniques may not properly function. A plurality of remote relay stations are located at points throughout the urban area, each station receiving and transmitting coded digital data and tone signals, the tone signals being used for phase ranging. Each of the vehicles is equipped with a transponder responsive only to the radio signal having a formatted message including the vehicle identification code with a ranging tone suitably impressed thereon. The formatted signal is transmitted from one of the relay stations at a first frequency and picked up by a preselected number of other relay stations as well as by the vehicle transponder. The vehicle transponder in turn generates a reply signal at a second frequency containing message data and a tone signal modulated on the second frequency for use in ranging, all of which signals are processed at a central location.
68 citations
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TL;DR: In this paper, a technique for the analysis of low-low intersatellite range-rate data in a gravity mapping mission is explored, based on standard tracking data analysis for orbit determination but using a spherical coordinate representation of the 12 epoch state parameters describing the baseline between the two satellites.
Abstract: A technique for the analysis of low-low intersatellite range-rate data in a gravity mapping mission is explored. The technique is based on standard tracking data analysis for orbit determination but uses a spherical coordinate representation of the 12 epoch state parameters describing the baseline between the two satellites. This representation of the state parameters is exploited to allow the intersatellite range-rate analysis to benefit from information provided by other tracking data types without large simultaneous multiple data type solutions. The technique appears especially valuable for estimating gravity from short arcs (e.g., less than 15 minutes) of data. Gravity recovery simulations which use short arcs are compared with those using arcs a day in length. For a high-inclination orbit, the short-arc analysis recovers low-order gravity coefficients remarkably well, although higher order terms, especially sectorial terms, are less accurate. Simulations suggest that either long or short arcs of GRACE data are likely to improve parts of the geopotential spectrum by orders of magnitude.
68 citations
Authors
Showing all 15293 results
Name | H-index | Papers | Citations |
---|---|---|---|
Peter J. Kahrilas | 109 | 586 | 46064 |
Edward J. Wollack | 104 | 732 | 102070 |
Duong Nguyen | 98 | 674 | 47332 |
Miroslav Krstic | 95 | 955 | 42886 |
Steven L. Suib | 89 | 862 | 34189 |
Gabriel M. Rebeiz | 87 | 806 | 32443 |
Charles W. Engelbracht | 83 | 210 | 28137 |
Paul A. Grayburn | 77 | 397 | 26880 |
Eric J. Huang | 72 | 201 | 22172 |
Thomas F. Eck | 72 | 150 | 32965 |
David M. Margolis | 70 | 227 | 17314 |
David W. T. Griffith | 65 | 288 | 14232 |
Gerhard Klimeck | 65 | 685 | 18447 |
Nickolay A. Krotkov | 63 | 219 | 11250 |
Olaf Stüve | 63 | 290 | 14268 |