Search NASA⌕ Search

SEARCH · Search NASA

Results for “Aeronautical communications”

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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1990

An aircraft Earth station for general aviation

While the focus has been international commercial air traffic, an opportunity exists to provide satellite communications to smaller aircraft. For these users equipment cost and weight critically impact the decision to install satellite communications equipment. Less apparent to the operator is the need for a system infrastructure that will be supported both regionally and internationally and that is compatible with the ground segment being installed for commercial aeronautical satellite communications. A system concept is described as well as a low cost terminal that are intended to satisfy the small aircraft market.

Matyas, R.↗
NASA NTRS1993

ACTS broadband aeronautical experiment

In the last decade, the demand for reliable data, voice, and video satellite communication links between aircraft and ground to improve air traffic control, airline management, and to meet the growing demand for passenger communications has increased significantly. It is expected that in the near future, the spectrum required for aeronautical communication services will grow significantly beyond that currently available at L-band. In anticipation of this, JPL is developing an experimental broadband aeronautical satellite communications system that will utilize NASA's Advanced Communications Technology Satellite (ACTS) as a satellite of opportunity and the technology developed under JPL's ACTS Mobile Terminal (AMT) Task to evaluate the feasibility of using K/Ka-band for these applications. The application of K/Ka-band for aeronautical satellite communications at cruise altitudes is particularly promising for several reasons: (1) the minimal amount of signal attenuation due to rain; (2) the reduced drag due to the smaller K/Ka-band antennas (as compared to the current L-band systems); and (3) the large amount of available bandwidth. The increased bandwidth available at these frequencies is expected to lead to significantly improved passenger communications - including full-duplex compressed video and multiple channel voice. A description of the proposed broadband experimental system will be presented including: (1) applications of K/Ka-band aeronautical satellite technology to U.S. industry; (2) the experiment objectives; (3) the experiment set-up; (4) experimental equipment description; and (5) industrial participation in the experiment and the benefits.

Abbe, Brian S.↗
NASA NTRS1984

Research and technology highlights of the Lewis Research Center

Highlights of research accomplishments of the Lewis Research Center for fiscal year 1984 are presented. The report is divided into four major sections covering aeronautics, space communications, space technology, and materials and structures. Six articles on energy are included in the space technology section.

Source record↗
NASA NTRS1988

Developing a global aeronautical satellite system

Arinc, an airline industry-owned and operated company in the United States, has taken steps toward establishing a global aeronautical satellite communications system. Plans call for initiation of a thin-route data operation in 1989, upgrading to establish voice communications via shared spot-beam transponders carried on other satellites, and deploying a worldwide network using dedicated satellites by 1994.

Dement, Donald K.↗
NASA NTRS1987

A high-capacity aeronautical mobile satellite system

This paper describes a conceptual system design for a satellite-based aeronautical safety communications system capable of serving both general aviation aircraft and commercial aviation aircraft in the contiguous U.S. in the mid-1990s. The space segment is described, including satellite locations and coverage, spacecraft configuration, eclipse capability and stationkeeping, transponder design, and mass and power. The spacecraft mass and power budgets are given. The air mobile terminals, ground segment, and frequency plan and channelization are discussed, and the data rate, modulation/demodulation/coding, and channel spacing are considered. The message format, frequency control, system capacity, and system sensitivity are discussed.

Sue, M. K.↗
NASA NTRS1988

Irreducible error rate in aeronautical satellite channels

The irreducible error rate in aeronautical satellite systems is experimentally investigated. It is shown that the introduction of a delay in the multipath component of a Rician channel increases the channel irreducible error rate. However, since the carrier/multipath ratio is usually large for aeronautical applications, this rise in the irreducible error rate should not be interpreted as a practical limitation of aeronautical satellite communications.

Davarian, F.↗
NASA NTRS1990

Proceedings of the Second International Mobile Satellite Conference (IMSC 1990)

Presented here are the proceedings of the Second International Mobile Satellite Conference (IMSC), held June 17-20, 1990 in Ottawa, Canada. Topics covered include future mobile satellite communications concepts, aeronautical applications, modulation and coding, propagation and experimental systems, mobile terminal equipment, network architecture and control, regulatory and policy considerations, vehicle antennas, and speech compression.

Huck, R. W.↗
NASA NTRS1991

Issues for the integration of satellite and terrestrial cellular networks for mobile communications

Satellite and terrestrial cellular systems naturally complement each other for land mobile communications, even though present systems have been developed independently. The main advantages of the integrated system are a faster wide area coverage, a better management of overloading traffic conditions, an extension to geographical areas not covered by the terrestrial network and, in perspective, the provision of only one integrated system for all mobile communications (land, aeronautical, and maritime). To achieve these goals, as far as possible the same protocols of the terrestrial network should be used also for the satellite network. Discussed here are the main issues arising from the requirements of the main integrated system. Some results are illustrated, and possible future improvements due to technical solutions are presented.

Delre, Enrico↗
NASA NTRS1973

1972 Highlights

This document includes Mariners to Mars, Pioneer to Jupiter, Orbiting Astronomical Observatory, Small Astronomy Satellite, sounding rockets, earth resources, Nimbus weather watcher, communication satellites, aeronautics, wind tunnel research, STOL, noise abatement, lifting bodies, US/Soviet cooperation, preparation for Skylab, and the Apollo 16 and 17 missions.

Source record↗
NASA NTRS1991

Propagation research in Japan

L-band propagation measurements for land-mobile, maritime, and aeronautical satellite communications have been carried out by using the Japanese Engineering Test Satellite-Five (ETS-5) which was launched in Aug. 1987. This paper presents propagation characteristics for each of the mobile satellite communication channels.

Wakana, Hiromitsu↗
NASA NTRS2000

3-D Sound for Virtual Reality and Multimedia

Technology and applications for the rendering of virtual acoustic spaces are reviewed. Chapter 1 deals with acoustics and psychoacoustics. Chapters 2 and 3 cover cues to spatial hearing and review psychoacoustic literature. Chapter 4 covers signal processing and systems overviews of 3-D sound systems. Chapter 5 covers applications to computer workstations, communication systems, aeronautics and space, and sonic arts. Chapter 6 lists resources. This TM is a reprint of the 1994 book from Academic Press.

Begault, Durand R.↗
NASA NTRS2007

Optimizations of a Hardware Decoder for Deep-Space Optical Communications

The National Aeronautics and Space Administration has developed a capacity approaching modulation and coding scheme that comprises a serial concatenation of an inner accumulate pulse-position modulation (PPM) and an outer convolutional code [or serially concatenated PPM (SCPPM)] for deep-space optical communications. Decoding of this code uses the turbo principle. However, due to the nonbinary property of SCPPM, a straightforward application of classical turbo decoding is very inefficient. Here, we present various optimizations applicable in hardware implementation of the SCPPM decoder. More specifically, we feature a Super Gamma computation to efficiently handle parallel trellis edges, a pipeline-friendly 'maxstar top-2' circuit that reduces the max-only approximation penalty, a low-latency cyclic redundancy check circuit for window-based decoders, and a high-speed algorithmic polynomial interleaver that leads to memory savings. Using the featured optimizations, we implement a 6.72 megabits-per-second (Mbps) SCPPM decoder on a single field-programmable gate array (FPGA). Compared to the current data rate of 256 kilobits per second from Mars, the SCPPM coded scheme represents a throughput increase of more than twenty-six fold. Extension to a 50-Mbps decoder on a board with multiple FPGAs follows naturally. We show through hardware simulations that the SCPPM coded system can operate within 1 dB of the Shannon capacity at nominal operating conditions.

quadratic polynomial interleaver↗
NASA NTRS2017

Millimeter Wave Systems for Airports and Short-Range Aviation Communications: A Survey of the Current Channel Models at mmWave Frequencies

Millimeter-wave (mmWave) communications will play a key role in enhancing the throughput, reliability, and security of next generation wireless networks. These advancements are achieved through the large bandwidth available in this band and through the use of highly directional links that will be used to overcome the large pathloss at these frequencies. Although the terrestrial application of mmWave systems is advancing at a rapid pace, the use of mmWave communication systems in aviation systems or airports is still in its infancy. This can be attributed to the challenges related to radio technology and lack of development, and characterization of mmWave wireless channels for the aviation field and the airport environment. Consequently, one of our goals is to develop methodologies that support mmWave air to ground links, and various links at airports, by applying new localization schemes that allow for application of highly directional links that can be deployed over longer distances despite the high path loss at mmWave frequencies. However, a very thorough understanding of the mmWave channel models are needed to enable such new applications. To this end, in this paper, we present a survey of the current channel models in the mmWave band. The 3-dimensional statistical channel model is also reviewed and its parameters and typical characteristics for this model are identified and computed through simulation for the Boise metropolitan area.

air traffic management↗
NASA NTRS2018

Assessing C2 Communications

The National Aeronautics and Space Administration's (NASA) Unmanned Aircraft Systems (UAS) Traffic Management (UTM) project works to develop tools and technologies essential for safely enabling civilian low-altitude UAS operations. Currently there is no established infrastructure to enable and safely manage the widespread use of low-altitude airspace and UAS operations, regardless of the type of UAS. The UTM technical challenge will develop comprehensive and validated airspace operations and integration requirements to safely enable large-scale persistent access to visual line of sight and autonomous beyond visual line of sight small UAS in low-altitude airspace. Within the UTM project, a number of communications technologies to support UTM command and control (C2) are under investigation. In particular, commercial networked cellular systems are being tested and assessed for their ability to meet the reliability, scalability, cybersecurity and redundancy required. NASA Glenn Research Center is studying some of the aspects of employing such networks for UTM C2 communications. This includes the development of a test platform for sensing and characterizing the airborne C2 communications environment at various altitudes and in various terrains and topologies, measuring such aspects as received signal strength and interference. System performance aspects such as latency in the link, handover performance, packet error loss rate, drop outs, coverage gaps and other aspects impacting UTM operation will also be assessed. In this paper we explore some of the C2 approaches being proposed and demonstrated in the UTM project, the reliability, availability and other general C2 performance requirements, and approaches to evaluating and analyzing UTM C2 links based on commercial cellular networks.

aircraft communications↗