SEARCH · Search NASA

Results for “Ka-Band”

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.

SourceResearch connectionFrom yearThrough year

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

At least 37 records · Page 2

All sources NASA NTRS DOE OSTI

DOE OSTI2026

W-Band ARM Scanning Cloud Radar (WSACR) 2nd Generation CF-Radial Spectral Data, Vertically-Pointing Scan, Co-Polarization Mode (a1)

ARM's scanning cloud radars are fully coherent dual-frequency, dual-polarization Doppler radars mounted on a common scanning pedestal. Each pedestal includes a Ka-band radar (2kW peak power) and the deployment location determines whether the second radar is a W-band (WSACR; 1.7 kW peak power) or X-band (XSACR; 20 kW peak power). Beamwidths at Ka and W bands are roughly matched at 0.3 degrees. Due to the narrow antenna beamwidth, ARM’s scanning cloud radars use scanning strategies that are unlike typical weather radars. Rather than focusing on plan position indicator, or PPI, scans, the Ka-SACR uses range height indicator, or RHI, scans at numerous azimuths to obtain cloud volume data. Measurements collected with the W-SACR are copolar and cross-polar radar reflectivity, Doppler velocity, spectra width and spectra when not scanning, and linear depolarization ration.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2026

W-Band ARM Scanning Cloud Radar (WSACR) 2nd Generation CF-Radial Spectral Data, Vertically-Pointing Scan, Cross Mode (a1)

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2026

W-Band ARM Scanning Cloud Radar (WSACR) 2nd Generation CF-Radial Spectral Data, Vertically-Pointing Scan, Cross-Polarization Model (a1)

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2025

KAZR2CFRGEQC

Ka-Band ARM Zenith Radar, 2nd Generation, General Sensitivity, Quality Control Corrections Applied

Radar Doppler↗

DOE OSTI2025

KAZR2CFRMDQC

Ka-Band ARM Zenith Radar, 2nd Generation, Medium Sensitivity, Quality Control Corrections Applied

Radar Doppler↗

DOE OSTI2025

KAZR2CFRPRQC

Ka-Band ARM Zenith Radar, 2nd Generation, Precipitation Mode, Quality Control Corrections Applied

Radar Doppler↗

DOE OSTI2025

Profiles of Radiative Fluxes at ENA

Profiles of radiative fluxes observed at the Atmospheric Radiation Measurement (ARM)’s Eastern North Atlantic (ENA) observatory along with the ancillary measurements are reported. The below-cloud drizzle properties were derived by combining the data from the ceilometer and Ka-band ARM Zenith Radar (KAZR) following the technique explained by Ghate et al. (2021 JAMC). The cloud and drizzle water path values were derived from the brightness temperatures reported by the microwave radiometer following the technique of Cadeddu et al. (2020 AMT). The cloud water path was then scaled to the KAZR-reported radar reflectivity to calculate profiles of liquid water content (LWC). Following the analysis from Ghate et al. (2023 JGR), cloud droplet effective radius was calculated using the number concentration value of 100 cm-3. The cloud properties, along with the thermodynamic properties, served as an input to the Rapid Radiative Transfer Model (RRTM) to yield profiles of radiative fluxes at a 1-minute temporal and 50-m vertical resolution. The fluxes were then averaged to hourly temporal resolution for analysis. In Mitra et al. (2025 JClim), the calculated profiles were compared against those derived from the satellite measurements (SYN1deg). Flux profiles from the SYN1deg and the thermodynamic and cloud properties used for deriving them are also reported here. Both all-sky and clear-sky radiative flux profiles were calculated. Due to the large data volume, the surface and top-of-atmosphere (TOA) radiative fluxes for the six-year period, and the hourly profiles of the radiative fluxes for January 2018, are submitted here. Full profiles of radiative fluxes calculated from the thermodynamic and cloud properties measured at the ENA site at 1-minute temporal and 50-m vertical resolution for a six-year period are available from the authors. Six files here correspond to the following data: 1_ENARAD_CERES_with_cld_amount_timeseries.nc: Time-series of hourly values of RRTM-simulated values of upwelling and downwelling fluxes at the surface and TOA, observed boundary-layer cloud fractions, and upwelling and downwelling fluxes from the SYN1deg from July 2015 to January 2022. 2_CERES_2018_at_CERES_levels.nc: SYN1deg radiative fluxes at six levels for the year 2018. 3_ENARad_2018_at_CERES_levels.nc: RRTM calculated fluxes at the SYN1deg vertical levels for the year 2018. 4_ENARad_rrtminputs_hourly_201801.nc: Thermodynamic and cloud properties used as an input to the RRTM for January 2018. 5_CERES_inputs_hourly_201801.nc: Thermodynamic and cloud properties utilized by SYN1deg algorithm for January 2018. 6_ENARAD_hourly_201801.nc: Full profiles of hourly averaged radiative fluxes from the RRTM simulations for January 2018.

Atmosphere↗

NASA NTRS1979

Effect of sample quantity on the results of ferromagnetic resonance studies of lunar samples

Quantitative ferromagnetic resonance (FMR) measurements at 9.5 and 35 GHz were made on lunar fines in order to determine the amount of single domain FE(0) and to ascertain the effect of sample quantity on the results of these experiments. Samples containing more than 10 micrograms of Fe(0) in an X-band TE(104) cavity, or more than 0.11 micrograms in a Ka-band cavity can cause errors greater than 1% in the quantitative determination of Fe(0), as well as cause anomalous broadening of the FMR line. Theoretical calculations were derived to show this effect which results from a nonlinear response of the FMR experiment with the sample quantity. Using samples of nominal weights, the amount of Fe(0) determined at 34 GHz was 1.1-1.8 times greater than at 9.5 GHz, while the linewidths increased by a factor of 1.2. As the particle size increases, the ratio of Fe(0) determined at 35 GHz to that determined at 9.5 GHz increases, suggesting that the additional iron is due to larger spheroidal particles which change from multidomain to single domain at the larger fields.

Goldberg, J. B.↗

NASA NTRS1979

Developing the next phase in NASA's satellite communications program

Since 1973, NASA has conducted hundreds of user experiments and demonstrations using the Applications Technology Satellites ATS-1, -3, and -6, and the Communications Technology Satellite CTS. Now, projections show that the commercial demand will continue to increase, soon exceeding the current technology's capacity. The next phase in NASA's satellite communication program include 30/20 GHz Ka-band technology, extending the current work in advanced multibeam antennas; a narrow-band system and technology study that could lead to mobile and transportable communication developments; and studies of future uses of technology in communications.

Dement, D. K.↗

NASA NTRS1980

An advanced domestic satellite communications system

An updated traffic projection for U.S. domestic satellite communications service covering a period of 15 years; mid-1980 to mid-1995 was prepared. This model takes into account expected technology advances and reductions in transmission costs, legislative and regulatory changes permitting increased competition, and rising energy costs which will encourage more extensive substitution of telecommunications for travel. The historical development and current status of satellite systems are discussed as well as the characteristics of follow-on systems. Orbital arc utilization, spacecraft configuration for single shuttle launch, Earth station configuration, and system costs are examined. Areas which require technology development include multiple beam frequency reuse antennas, on-board switching, intersatellite links, and ka-band operation. Packing and deployment schemes for enclosing the satellite within the shuttle orbiter bay must also be devised.

Source record↗

NASA NTRS1980

Advanced communications satellites

The increase in demand for satellite communications services brought about shortages in available transponder capacity, especially at C-band. Interest shifted to the Ku-band frequency and currently carriers are rapidly moving to secure orbital slots for future satellite development. Projections of communications service demands over the next decade indiate growth in voice, data, and video services such that saturation of both C-band and Ku-band will occur by 1990. Emphasis must and will shift to Ka-band (20/30 GHz) frequency for fixed-satellite service. Advanced technologies such as multibeam antennas coupled with on-board satellite switching to allow implementation in this band of very high capacity satellite systems will be applied to meet the demand. Satellite system concepts that are likely in the 1990's and are likely to bring a new dimension to satellite delivered communication service are presented. The NASA 30/20 GHz communications satellite system demonstration program is discussed with emphasis on the related technology development.

Sivo, J. N.↗

NASA NTRS1980

A new phase for NASA's communications satellite program

NASA's research in communications satellite technology is discussed, including orbit-efficient techniques and applications by the commercial sector. Attention is given to expanding the capacities of the C-band (6-4 GHz) and the Ku-band (14-11 GHz), opening the Ka-band (30/20 GHz), broadly applied 're-use' of the spectrum, and developing multibeam spacecraft antennas with on-board switching. Increasing wideband services in video, high-speed data, and voice trunking is considered, as are narrow-band systems that may be used for data collection or public safety, with possible expansion to a thin-route satellite system. In particular, communication for medical, disaster, or search-and-rescue emergencies may be met by the integration of a satellite service with land mobile communications via terrestrial radio links. Also considered is a large geostationary platform providing electrical power, thermal rejection, and orbital station-keeping for many communications payloads.

Dement, D. K.↗

NASA NTRS1981

The 30/20 GHz demonstration system SSUS-D/BSE

The systems consisting of a 30/20 GHz communication satellite featuring a multiple fixed beam and scanning beam antenna, SS-TDMA, onboard processing and high power TWT's and IMPATT amplifiers, a trunking space-diversity Earth station, a customer premise system (CPS) portable Earth station and a Master Control Station. Hardware, software and personnel are included to build and launch one satellite and to carry on a two year experimentation and demonstration period of advanced Ka-band systems concepts and technology. Included are first level plans identifying all tasks, a schedule for system development and an assessment of critical technology and risk and a preliminary experiments plan.

Source record↗

NASA NTRS1980

Adaptive rain fade compensation

A large available margin must be provided for satellite communications systems operating near 20 GHz, which occasionally experience fades due to rain attenuation. It is proposed that this margin may be achieved in high-capacity FDMA satellites by dynamically providing a large margin to those links which are experiencing deep fades, while maintaining a small fade margin on all others. Single-beam SCPC operation and multiple-beam, satellite-switched FDMA systems are described, and the optimization of the dynamic FDMA links in a severely fading environment is investigated. A solution is derived which takes into account: (1) transponder intermodulation distortion, (2) cochannel and cross-polarization antenna interference, and (3) rain fade characteristics. The sample system configuration presented shows that such systems reach availability levels approaching 0.9999 at Ka-Band.

Rautio, J. C.↗

NASA NTRS1980

30/20 GHz demonstration system for improving orbit utilization

To guard against severe rain losses at 30 and 20 GHz, techniques are being developed which provide the high antenna gain needed to increase communications margins and frequency reuse capability through beam isolation, while providing complete coverage of the U.S. Effective bandwidths from a single satellite location may then reach tens of gigahertz, with capacity tailored to match nonuniform geographic demand patterns. Satellite onboard processing which includes forward-error-correction and the routing of channels to terminals will reduce scanning antenna requirements and increase rain margins, through the adaptive use of system margins to support those terminals experiencing rain. These antenna and onboard processing techniques are adaptable to C-band and Ku-band, in addition to Ka-band.

Holmes, W. M., Jr.↗

NASA NTRS1982

Concept for advanced satellite communications and required technologies

The advanced communications technology satellite (ACTS) program of NASA is aimed at the development of high risk technologies that will enable exploiting higher frequency bands and techniques for improving frequency reuse. The technologies under development include multiple beam spacecraft antennas, on-board switching and processing, RF devices and components and advanced Earth stations. The program focus is on the Ka-band (30/20 GHz) as the implementing frequency since it has five times the bandwidth of either the C- or Ku-bands. However, the technology being developed is applicable to other frequency bands as well and will support a wide range of future communications systems required by NASA, other Government agencies and the commercial sector. An overview is presented of an operational 30/20 GHz satellite system that may evolve. How the system addresses service requirements is discussed, and the technology required and being developed is considered.

Ramler, J. R.↗

NASA NTRS1982

Concept for advanced satellite communications and required technologies

The advanced communications technology satellite (ACTS) program of NASA is aimed at the development of high risk technologies that will enable exploiting higher frequency bands and techniques for improving frequency reuse. The technologies under development include multiple beam spacecraft antennas, on-board switching and processing, RF devices and components and advanced earth stations. The program focus is on the Ka-band (30/20 GHz) as the implementing frequency since it has five times the bandwidth of either the C- or Ku-bands. However, the technology being developed is applicable to other frequency bands as well and will support a wide range of future communications systems required by NASA, other Government agencies and the commercial sector. An overview is presented of an operational 30/20 GHz satellite system that may evolve. How the system addresses service requirements is discussed, and the technology required and being developed is considered. Previously announced in STAR as N83-11210

Ramler, J. R.↗

DOE OSTI2025

KAZR-based snowfall rates during SAIL

This data set provides KAZR radar based retrievals of snowfall rates for the two cold periods of the SAIL campaign (NOV 2021- APR 2022 and NOV 2022 - APR 2023).

54 ENVIRONMENTAL SCIENCES↗