Dr. Oscar S. Alvarez-Salazar Profile

Dr. Oscar S. Alvarez-Salazar

Senior Engineer at Jet Propulsion Lab

SPIE Involvement:

Author

Publications (17)

Proceedings Article | 12 March 2024 Presentation + Paper

Presentation + Paper

Deep space optical communications technology demonstration

Abhijit Biswas, Meera Srinivasan, Kenneth Andrews, Erik Alerstam, Angel Velasco, Malcolm Wright, Joseph Kovalik, Brett Douglas, Jason Allmaras, Vincent Van Rhein, Emma Wollman, Ryan Rogalin, Sean Meenehan, David Zhu, Dylan Conway, Oscar Alvarez-Salazar, Christopher Pong, Herrick Chang, Marcus Wilkerson, Edwin Grigorian, Nathaniel Richard, Daniel Cho, Yuri Beregovski, William Buehlman, Luke Stewart, Mark Brewer, Christine Chen, Vachik Garkanian, Gerardo Ortiz, Daniel Macdonald, Sarah Haque, Matthew Shaw, Christopher Leffler, Greg Agnes, Joel Johnson, Arthur Na-Nakornpanom, Rogeliio Rosas, Jason Mumolo, Oliver Lay, Roger O'Brient, Marcum Martz, Gregory Miles, Kitt Matthews, Hernan Erlig, Dorothy Lewis, Anthony Mittskus, Serge Dubovitsky, William Klipstein

Proceedings Volume 12877, 1287706 (2024) https://doi.org/10.1117/12.3001750

KEYWORDS: Space operations, Telescopes, Signal processing, Receivers, Transmitters, Laser safety, Interfaces, Sensors, Deep space optical communications, Actuators

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Proceedings Article | 12 March 2024 Presentation + Paper

Presentation + Paper

Deep space optical communications (DSOC) technology demonstration pre-launch validation and performance tests with the laser test evaluation station (LTES)

Angel Velasco, Jason Allmaras, Joseph Kovalik, Vachik Garkanian, Brett Douglas, Erik Alerstam, Malcolm Wright, Sarah Haque, Vincent Van Rhein, Daniel Macdonald, David Zhu, Oscar Alvarez-Salazar, Dylan Conway, Gerardo Ortiz, Sabino Piazzolla, Yanhua Anderson, Kenneth Andrews, Meera Srinivasan, Abhijit Biswas

Proceedings Volume 12877, 1287707 (2024) https://doi.org/10.1117/12.3008378

KEYWORDS: Cameras, Space operations, Scintillation, Receivers, Laser communications, Laser communication terminals, Calibration, Short wave infrared radiation, Engineering, Control systems

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Proceedings Article | 24 July 2018 Paper

Paper

Overview of the 4m baseline architecture concept of the habitable exoplanet imaging mission (HabEx) study

Gary Kuan, Keith Warfield, Bertrand Mennesson, Alina Kiessling, Stefan Martin, Joel Nissen, Stuart Shaklan, Oscar Alvarez-Salazar, Milan Mandic, David Webb, H. Philip Stahl, Steve Warwick

Proceedings Volume 10698, 106980Q (2018) https://doi.org/10.1117/12.2314241

KEYWORDS: Space telescopes, Telescopes, Coronagraphy, Exoplanets, Mirrors, Space operations, Ultraviolet radiation, Stars, Observatories, Laser sintering

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Proceedings Article | 6 July 2018 Presentation + Paper

Presentation + Paper

HabEx: A high-precision pointing architecture using microthrusters and a fine steering mirror

Milan Mandić, Oscar Alvarez-Salazar, Alina Kiessling

Proceedings Volume 10698, 106980U (2018) https://doi.org/10.1117/12.2315545

KEYWORDS: Telescopes, Coronagraphy, Space telescopes, Wavefront sensors, Exoplanets, Cameras, Line of sight pointing

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Proceedings Article | 13 April 2018 Paper

Paper

Progress towards picometer accuracy laser metrology for the space interferometry mission: update

Peter Halverson, Oscar Alvarez-Salazar, Alireza Azizi, Frank Dekens, Bijan Nemati, Feng Zhao

Proceedings Volume 10568, 105682L (2018) https://doi.org/10.1117/12.2500128

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Proceedings Article | 11 November 2014 Paper

Paper

Mission design for NISAR repeat-pass Interferometric SAR

Oscar Alvarez-Salazar, Sara Hatch, Jennifer Rocca, Paul Rosen, Scott Shaffer, Yuhsyen Shen, Theodore Sweetser, Peter Xaypraseuth

Proceedings Volume 9241, 92410C (2014) https://doi.org/10.1117/12.2074162

KEYWORDS: Interferometry, Interferometric synthetic aperture radar, Synthetic aperture radar, Radar, Space operations, Diamond, Observatories, Antennas, Calibration, Received signal strength

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Proceedings Article | 6 March 2014 Paper

Paper

Pointing, acquisition, and tracking architecture tools for deep-space optical communications

Swati Mohan, Oscar Alvarez-Salazar, Kevin Birnbaum, Abhijit Biswas, William Farr, Hamid Hemmati, Shawn Johnson, Geraldo Ortiz, Kevin Quirk, Zahidul Rahman, Martin Regher, Farheen Rizvi, Joel Shields, Meera Srinivasan

Proceedings Volume 8971, 89710H (2014) https://doi.org/10.1117/12.2042704

KEYWORDS: Optical communications, Sensors, Space operations, Systems engineering, Asteroids, Error analysis, Receivers, Transmitters, Ka band, Signal attenuation

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Proceedings Article | 22 July 2010 Paper

Paper

On-orbit dynamics and controls system architecture for SIM Lite

Oscar Alvarez-Salazar

Proceedings Volume 7734, 77341I (2010) https://doi.org/10.1117/12.856505

KEYWORDS: Interferometers, Stars, Control systems, Cameras, Telescopes, Metrology, Space telescopes, Fringe analysis, Sensors, Interferometry

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Proceedings Article | 20 October 2004 Paper

Paper

Kite: status of the external metrology testbed for SIM

Frank Dekens, Oscar Alvarez-Salazar, Alireza Azizi, Steven Moser, Bijan Nemati, John Negron, Timothy Neville, Daniel Ryan

Proceedings Volume 5491, (2004) https://doi.org/10.1117/12.549797

KEYWORDS: Metrology, Stars, Data modeling, Interferometers, Heterodyning, Space operations, Motion measurement, Switches, Bragg cells, Sensors

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Proceedings Article | 20 October 2004 Paper

Paper

Terrestrial Planet Finder cryogenic delay line development

Robert Smythe, Mark Swain, Oscar Alvarez-Salazar, James Moore

Proceedings Volume 5491, (2004) https://doi.org/10.1117/12.552260

KEYWORDS: Ferroelectric materials, Cryogenics, Metrology, Servomechanisms, Planets, Nitrogen, Interferometers, Amplifiers, Mirrors, Real-time computing

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Proceedings Article | 20 October 2004 Paper

Paper

Metrology system for Space Interferometry Mission's system testbed 3

Oscar Alvarez-Salazar, Alireza Azizi, Yekta Gursel, George Sun, Jens Fischer, Arshak Avanesyan, John Shaw

Proceedings Volume 5491, (2004) https://doi.org/10.1117/12.549694

KEYWORDS: Metrology, Error analysis, Interferometers, Motion measurement, Interferometry, Stars, Motion estimation, Monte Carlo methods, Algorithm development, Polarizers

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Proceedings Article | 20 October 2004 Paper

Paper

SIM system testbed: 3-baseline stellar interferometer on a 9-meter-long flexible structure

Oscar Alvarez-Salazar, Renaud Goullioud, Alireza Azizi

Proceedings Volume 5491, (2004) https://doi.org/10.1117/12.549690

KEYWORDS: Interferometers, Stars, Metrology, Mirrors, Error analysis, Interferometry, Device simulation, Space operations, Motion measurement, Reflectors

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Proceedings Article | 26 February 2003 Paper

Paper

Dim star fringe stabilization demonstration using pathlength feed-forward on the SIM testbed 3 (STB3)

Renaud Goullioud, Oscar Alvarez-Salazar, Bijan Nemati

Proceedings Volume 4852, (2003) https://doi.org/10.1117/12.460714

KEYWORDS: Interferometers, Stars, Metrology, Beam splitters, Interference (communication), Control systems, Space operations, Mirrors, Sensors, Motion measurement

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Proceedings Article | 26 February 2003 Paper

Paper

SIM testbed 3 real-time control software

Elizabeth McKenney, Oscar Alvarez-Salazar

Proceedings Volume 4852, (2003) https://doi.org/10.1117/12.460717

KEYWORDS: Interferometers, Stars, Servomechanisms, Control systems, Metrology, Photons, Signal to noise ratio, Ferroelectric materials, Actuators, Real-time computing

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Proceedings Article | 26 February 2003 Paper

Paper

Mitigation of atmospheric effects in SIM's astrometric interferometer testbed 3

Oscar Alvarez-Salazar, Renaud Goullioud, Bijan Nemati, Alireza Azizi

Proceedings Volume 4852, (2003) https://doi.org/10.1117/12.460724

KEYWORDS: Interferometers, Stars, Metrology, Atmospheric sciences, Atmospheric optics, Signal to noise ratio, Atmospheric propagation, Filtering (signal processing), Optical tracking, Electronic filtering

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The Space Interferometry Mission's (SIM) shared-baseline astrometric interferometer System Test Bed 3 (STB3) has been constructed at JPL. STB3's objective is to use two of its interferometers (guides) for low frequency (0 to 1 Hz) fringe stabilization in the third one (science). This approach - being proposed for the first time in the context of space based observatories - is needed given the dim nature of science stars to be observed by SIM. Fringe stability is mostly affected by the low frequency attitude motion of the test bed's instrument table, with the inevitable exception of instrument vibration, thermal drift, and atmospheric fluctuations. Relative changes in table attitude cause optical path changes in the guide interferometers, which are tracked, linearly combined and fed forward to the science interferometer's active delay line to stabilize its optical path. This technique for tracking fringes in the science interferometer is possible because the position of the guide stars relative to the science star is well known. This open loop fringe tracking technique is dubbed Path-length Feed Forward, or PFF. In STB3, current fringe stability in the science interferometer using the PFF technique is at 50 to 60 nanometers RMS (from 0 to 500 Hz). Compare this to 15 to 20 nm RMS fringe stability in the guide interferometers, which operate in closed loop mode. Vibration, thermal drift and atmospherics in the science and guide interferometers are largely eliminated with the use of an internal metrology system. By design, mechanical vibrations are above the bandwidth of the interferometer system, and are passively rejected. Nevertheless, the internal metrology system can easily reject current low-level vibrations in STB3 down to the 6-nanometer RMS level. Fringe tracking error in the science interferometer due to atmospherics is currently about 40 nanometers RMS at frequencies below 1.0 Hz. In SIM, the error in this low frequency band must be no more than 6 nm RMS. This error arises because the optical path stabilized by the internal metrology system is not equal to taht of the starlight, so not all atmospheric fluctuations in the starlight path can be stabilized. Therefore, there is a need to reduce the strength of atmospheric fluctuations or to filter them from the PFF command. In STB3 the strength of atmospheric fluctuations is already reduced with the use of optical path enclosures, which brought these fluctuations down from ~170nm RMS to their current levels of ~66nm RMS with a spread of 20nm. Simulations show that signal to noise ratios are generally not sufficient to filter atmospheric errors on-line.

Proceedings Article | 6 May 1994 Paper

Paper

Active vibration suppression using modular elements

Allen Bronowicki, John Innis, Scott Casteel, George Dvorsky, Oscar Alvarez, Erik Rohleen

Proceedings Volume 2190, (1994) https://doi.org/10.1117/12.175226

KEYWORDS: Analog electronics, Actuators, Sensors, Amplifiers, Electronics, Vibration control, Microchannel plates, Control systems, Ferroelectric materials, Bandpass filters

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Proceedings Article | 8 September 1993 Paper

Paper

Experiences with active damping and impedance-matching compensators

Robert Betros, Oscar Alvarez, Allen Bronowicki

Proceedings Volume 1917, (1993) https://doi.org/10.1117/12.152802

KEYWORDS: Sensors, Intelligence systems, Actuators, Smart structures, Digital signal processing, Ferroelectric materials, Control systems, Linear filtering, Optical simulations, Oscillators

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Showing 5 of 17 publications

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