Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “telecommunications engineering”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10

Distributed Acoustic Sensing for Whale Vocalization Monitoring: A Vertical Deployment Field Test

Abstract There is growing interest in floating offshore wind turbine (FOWT) technology, where turbines are installed on floating structures anchored to the seabed, allowing wind energy development in areas unsuitable for traditional fixed-platform turbines. Responsible development requires monitoring the impact of FOWTs on marine wildlife, such as whales, throughout the operational lifecycle of the turbines. Distributed acoustic sensing (DAS)—a technology that transforms fiber-optic cables into vibration sensor arrays—has been demonstrated for acoustic monitoring of whales using seafloor telecommunications cables. However, no studies have yet evaluated DAS performance in dynamic, engineered environments, such as floating platforms or moving vessels with complex, dynamic strain loads, despite their relevance to FOWT settings. This study addresses that gap by deploying DAS aboard a boat in Monterey Bay, California, where a fiber-optic cable was lowered using a weighted and suspended mooring line, enabling vertical deployment. Humpback whale vocalizations were captured and identified in the DAS data, noise sources were identified, and DAS data were compared to audio captured by a standalone hydrophone attached to the mooring line and a nearby hydrophone on a cabled observatory. This study is unique in: (1) deploying DAS in a vertical deployment mode, where noise from turbulence, cable vibrations, and other sources posed additional challenges compared to seafloor DAS applications; (2) demonstrating DAS in a dynamic, nonstationary setup, which is uncommon for DAS interrogators typically used in more stable environments; and (3) leveraging looped sections of the cable to reduce the noise floor and mitigate the effects of excessive cable vibrations and strain. This research demonstrates DAS’s ability to capture whale vocalizations in challenging environments, highlighting its potential to enhance underwater acoustic monitoring, particularly in the context of renewable energy development in offshore environments.

Saw, Jaewon↗

Progress Toward Standards for the Seamless Interoperability of Broadband Satellite Communication Networks

The realization of the full potential of the National Information Infrastructure (NH) and Global Information Infrastructure (GII) requires seamless interoperability of emerging satellite networks with terrestrial networks. This requires a cooperative effort between industry, academia and government agencies to develop and advocate new, satellite-friendly communication protocols and modifications to existing communication protocol standards. These groups have recently come together to actively participating in a number of standards making bodies including: the Internet Engineering Task Force (IETF), the Asynchronous Transfer Mode (ATM) Forum, the International Telecommunication Union (ITU) and the Telecommunication Industry Association MA) to ensure that issues regarding efficient use of these protocols over satellite links are not overlooked. This paper will summarize the progress made toward standards development to achieve seamless integration and accelerate the deployment of multimedia applications.

Ivancic, William D.↗

Jet Propulsion Laboratory: Annual Report 2003

If you stepped outdoors on the final evening of 2003 and looked up into the night sky, many celestial events were taking place. A hundred million miles away from Earth, a dust storm swirled across the terracotta peaks and gullies of Mars, as two six-wheeled robots bore down on the planet. They were soon to join two orbital sentries already stationed there. A few hops across the inner solar system, another spacecraft was closing in on a ball of ice and rock spewing forth a hailstorm of dust grains, heated as it swung in toward the Sun. Closer in, two newly lofted space telescopes scanned the skies, their mirrors gathering photons that had crossed the empty vastness of space for billions of years, recording ancient events in unimaginably distant galaxies. And streaking overhead every few minutes directly above our home planet, a handful of satellites was recording the unfolding events of a tropical cyclone off the east coast of Africa and a blizzard that carpeted the northwestern United States. As 2003 drew to a close, the Jet Propulsion Laboratory was on the cusp of an extraordinarily busy period, a time when JPL will execute more fly-bys, landings, sample returns and other milestones than at any other time in its history. The exploration we undertake is important for its own sake. And it serves other purposes, none more important than inspiring the next generation of explorers. If the United States wishes to retain its status as a world leader, it must maintain the technological edge of its workforce. What we do here is the stuff of dreams that will inspire a new generation to continue the American legacy of exploration.

Jet Propulsion Laboratory (JPL)↗

Space Telecommunications Radio System (STRS) Application Repository Design and Analysis

The Space Telecommunications Radio System (STRS) Application Repository Design and Analysis document describes the STRS application repository for software-defined radio (SDR) applications intended to be compliant to the STRS Architecture Standard. The document provides information about the submission of artifacts to the STRS application repository, to provide information to the potential users of that information, and for the systems engineer to understand the requirements, concepts, and approach to the STRS application repository. The STRS application repository is intended to capture knowledge, documents, and other artifacts for each waveform application or other application outside of its project so that when the project ends, the knowledge is retained. The document describes the transmission of technology from mission to mission capturing lessons learned that are used for continuous improvement across projects and supporting NASA Procedural Requirements (NPRs) for performing software engineering projects and NASAs release process.

information retrieval↗

Low-Cost Intermediate-Temperature Fuel-Flexible Protonic-Ceramic Fuel Cell and Stack

Large, centralized power plants are currently the most efficient way to convert fuels such as natural gas to electricity. Fuel cells, however, could become highly efficient generators across a range of sizes from tens of watts to megawatts. In particular, fuel cells with an electrical efficiency of 50% could displace small generators of 25 kilowatts (kW) or less in applications such as remote power, telecommunications, and residential cogeneration. Current 25 kW natural gas generators employing internal combustion engines are typically only 25-30% efficient and expensive to maintain. Furthermore, fuel cells could provide valuable services to the grid, such as the ability to ramp power up or down in response to load conditions. While there are different types of fuel cells, each with their strengths and weaknesses, fuel cells generally are very expensive. For example, lower temperature fuel cells can be started up quickly, but require highly pure hydrogen fuel and expensive catalysts. High-temperature fuel cells can operate on a range of fuels, but they have costly system components and can degrade rapidly.

30 DIRECT ENERGY CONVERSION↗

Telecommunications and data acquisition

Deep Space Network progress in flight project support, tracking and data acquisition research and technology, network engineering, hardware and software implementation, and operations is reported. In addition, developments in Earth based radio technology as applied to geodynamics, astrophysics, and the radio search for extraterrestrial intelligence are reported.

Renzetti, N. A.↗

An Optimal Design For Steerable Dish Antenna With BWG

New design proposed for highly-efficient 34-m-diameter millimeter-wavelength antennas of NASA's Deep Space Network. Incorporates axial beam waveguide, BWG, and improved structure to maintain shape and alignment of reflecting surfaces. General approach to conceptual construction of structure to modularize overall system so critical constraint conditions pertaining to microwave optics and structural performance satisfied. Design retrofitted to existing NASA Deep Space Network 34-m antennas, or used as basis to build large ground-based steerable antennas. Engineering concepts involved in design adapted to design of other large, steerable antennas for telecommunications, radio astronomy, and military uses.

Chuang, K. L.↗

Jet Propulsion Laboratory: Annual Report 1999

The Jet Propulsion Laboratory, located in the foothills near Pasadena, California, is the nation's lead center for the robotic exploration of space. Intense activity in space missions was the hallmark of the Jet Propulsion Laboratory as a new generation of smaller, less expensive spacecraft were sent out from Earth. From late 1998 to mid-1999, JPL launched a craft testing a futuristic ion engine, an orbiter and lander bound for Mars, a mission to fly by a comet and return a sample of its dust to Earth, a small infrared telescope, and an Earth-circling satellite that uses radar to gauge winds over the oceans. This unprecedented schedule resulted in spectacular achievements, tempered by highly visible mission losses. Weighed together, the successes and failures dramatically underscored the difficulty and risk involved in the unique business of space science and exploration. Among the achievements, the ion-engine-powered Deep Space 1, comet-bound Stardust and Earth-orbiting SeaWinds were joined by such ongoing missions as Mars Global Surveyor, Galileo and Cassini in delivering on their promise and, in some cases, providing surprising new views of space and Earth. At the same time, mission teams were disappointed by the losses of an orbiter and lander at Mars, as well as a small infrared telescope. JPL worked closely with NASA to learn from these experiences and build successful future missions. The Laboratory also achieved a key goal by winning the International Organization of Standards' 'ISO 9001' certification - a standard shared by the world's best engineering organizations. As the year rolled to a close, clocks rolled over from 1999 to 2000. Operations teams at JPL and NASA watched with satisfaction as a major campaign of Year 2000 readiness paid off with no problems among the thousands of computer systems that support the Laboratory's missions. With that auspicious beginning, JPL was positioned to step into the 21st century and embark on even yet unimagined future explorations.

Jet Propulsion Laboratory (JPL)↗

DGPS with NASA's ACTS

The U.S. Army Topographic Engineering Center, concerned about frequency license problems inherent with operating data-ready radios to support differential GPS (DGPS), learned of an experiment program the National Aeronautics and Space Administration (NASA) was sponsoring with its prototype digital satellite - the Advanced Communications Technology Satellite (ACTS). ACTS was designed to evaluate many new, untested technologies for eventual transfer to U.S. telecommunications and related industries. The new technologies promised greater data transmission rates and significantly reduced transmission latency. recognizing these benefits, the Topographic Engineering Center designed a DGPS experiment using an ACTS datalink with baselines of 200 kilometers and longer to learn what positional accuracy was possible with leading-edge satellite telecommunications technology.

Dendy, Roger↗

Diffractive optical computing in free space

Abstract Structured optical materials create new computing paradigms using photons, with transformative impact on various fields, including machine learning, computer vision, imaging, telecommunications, and sensing. This Perspective sheds light on the potential of free-space optical systems based on engineered surfaces for advancing optical computing. Manipulating light in unprecedented ways, emerging structured surfaces enable all-optical implementation of various mathematical functions and machine learning tasks. Diffractive networks, in particular, bring deep-learning principles into the design and operation of free-space optical systems to create new functionalities. Metasurfaces consisting of deeply subwavelength units are achieving exotic optical responses that provide independent control over different properties of light and can bring major advances in computational throughput and data-transfer bandwidth of free-space optical processors. Unlike integrated photonics-based optoelectronic systems that demand preprocessed inputs, free-space optical processors have direct access to all the optical degrees of freedom that carry information about an input scene/object without needing digital recovery or preprocessing of information. To realize the full potential of free-space optical computing architectures, diffractive surfaces and metasurfaces need to advance symbiotically and co-evolve in their designs, 3D fabrication/integration, cascadability, and computing accuracy to serve the needs of next-generation machine vision, computational imaging, mathematical computing, and telecommunication technologies.

36 MATERIALS SCIENCE↗

The telecommunications and data acquisition report

Deep Space Network progress in flight project support, tracking and data acquisition research and technology, network engineering, hardware and software implemention, and operations is documented. In addition, developments in Earth based radio technology as applied to geodynamics, astrophysics, and the radio search for extraterrestrial intelligence are reported.

Renzetti, N. A.↗

ATS-6 engineering performance report. Volume 4: Television experiments

Experiments sponsored by the US Department of Health Education and Welfare are discussed, including telecommunications, Alaskan health service, Appalachian education satellite project, and the University of the West Indies. The Satellite Instructional Television Experiment in India is reviewed. Independent television experiments are addressed, including AIDSAT and Project Look Up.

Wales, R. O.↗

The Telecommunications and Data Acquisition Report

Deep Space Network progress in flight project support, tracking and data acquisition research and technology, network engineering, hardware and software implementation, and operations is documented. In addition, developments in Earth-based radio technology as applied to geodynamics, astrophysics and the radio search for extraterrestrial intelligence are reported.

Posner, E. C.↗