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W. Linwood Jones - IEEE Xplore Author Profile

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Before a space launch is approved by the US government, the launch contractor must demonstrate that all flight rules and safety constraints are fully satisfied. One important aspect is that the vehicle and payload provide high quality RF communications during the booster portion of flight. To this end conservative analyses are performed that demonstrate that high signal-to-noise ratios (SIN) are a...Show More
Typically, every 3–5 years, the brightness temperature (Tb) data products for the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) were reprocessed to incorporate improvements in signal processing algorithms. In 2017, the TMI 1B data product, in Global Precipitation Measurement (GPM) version 5 (V05), was updated with an improved correction for a slightly emissive main reflector (M...Show More
This paper presents characterization of collocated Ku- and Ka-band ocean surface normalized radar cross section ($\sigma^{0}$) measurements over nadir-to-18° earth incidence angles using Global Precipitation Measurement (GPM) mission dual frequency precipitation radar (DPR) data. Empirical geophysical model functions (GMF) were derived, and isotopic and directorial sensitivity were evaluated at bo...Show More
This paper presents a combined active/passive ocean vector wind (OVW) retrieval from the Global Precipitation Measurement Core Observatory (GPM-CO). Although the GPM-CO was designed to observe global precipitation, we demonstrate the potential for providing a climate quality OVW data product for the multi-decade GPM- TRMM era. Development of GMFs for the Ku- and Ka-band dual frequency Precipitatio...Show More
This paper presents TRMM microwave imager (TMI) main reflector new physical temperatures (Tphy) look-up tables to produce next version of TMI brightness temperature products (GPM V07 Tbs). A modified and improved radiative transfer theory (RTM) based approach was used to determine the new physical temperatures (Tphy) for entire TRMM lifetime. New brightness temperatures (Tbs) were derived using ne...Show More
In this paper, we demonstrate the feasibility of remote sensing of ocean vector wind (OVW) from the Global Precipitation Measurement (GPM) satellite. By combining its active normalized radar cross section (σ0), and passive microwave brightness temperature (Tbs) measurements, ocean surface wind vectors were retrieved and validated by comparison with collocated ASCAT wind products. The algorithm is ...Show More
This article presents a novel ocean vector wind (OVW) retrieval algorithm for remote sensing of ocean winds, using the precipitation radar (PR) and tropical rainfall measurement mission (TRMM) microwave imager (TMI) that operated for >17 years on the TRMM observatory. In this study, the wind speed and anisotropic wind direction (WD) characteristics of the ocean backscatter and brightness temperatu...Show More
In this paper, we describe the development of Geophysical Model Functions (GMF) for remote sensing of ocean vector winds using the Precipitation Radar (PR) and TRMM Microwave Imager (TMI) that operated for > 17 years on the Tropical Rainfall Measurement Mission (TRMM) observatory. Wind speed and anisotropic wind direction characteristics of the ocean backscatter and brightness temperature were emp...Show More
This paper is continuation of previous work investigating the sensitivity of propagation loss calculations to changes in relative permittivity assigned to features of a sitespecific dense urban landscape. This work adds complexity to the model simulations by introducing non-uniform dielectric definition of the lower boundary condition of the calculation domain. Simulations were done using the Vari...Show More
In this work, we investigate after the performance of an S-band, circularly polarized patch antenna installed on a Launch Vehicle (LV) compromised by the launching spacecraft structure and the unpredicted loss of critical telemetry. During any space launch, on-board Radio Frequency (RF) Telemetry, Tracking & Command (TT&C) systems must satisfy RF link requirements for monitoring of launch vehicle ...Show More
When oceanic rainfall occurs, it creates a vertical salinity profile that is fresher at the surface. This freshwater lens is mixed downward by turbulent diffusion, dissipating over a few hours until the upper layer (1-5 m depth) becomes well mixed. Thus, there will be a transient bias between the in situ bulk salinity and the satellite-measured sea surface salinity (SSS) (representative of the fir...Show More
This paper presents diurnal ocean vector wind measurements derived using the Precipitation Radar (PR) and the TRMM Microwave Imager (TMI) remote sensors on the Tropical Rainfall Measurement Mission (TRMM). An active/passive OVW retrieval algorithm is described, and comparisons of TRMM OVW measurements with collocated nature runs GDAS wind vector retrievals are shown. Flying in a low-earth non-sun ...Show More
This paper evaluates the performance of the Variable Terrain Radiowave Parabolic Equation (VTRPE) algorithm for calculating the forward electromagnetic propagation loss for a site specific dense urban environment. While the VTRPE code has proven capable of handling terrain profiles with high variability, this is the first test of the model against an urban profile, where the landscape consists of ...Show More
In this paper, we describe a Monte Carlo technique to simulate the active and passive remote sensor observations (normalized ocean radar backscatter, σ° and brightness temperatures, Tb) and to estimate the resulting wind direction retrieval accuracy. A critical part of the simulation was to calculate the satellite/sensor geometry for each point along the orbital ground track. For this, we used the...Show More
The Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI), launched in late November 1997, has provided a > 17-year record of tropical precipitation measurements, and prior to the launch of the global precipitation measurements (GPM) satellite in February 2014, the TMI served as the radiometric transfer standard for the TRMM constellation radiometers. Thus, the radiometric calibration ...Show More
This paper discusses the intersatellite radiometric calibration for microwave sounders in support of NASA’s Global Precipitation Measurement (GPM) mission. This paper is an extension of previous GPM Intersatellite Calibration Working Group work, which assesses the robustness of the Central Florida Remote Sensing Laboratory “double difference” technique for sounders intercalibration. In this paper,...Show More
This paper describes the technical approach to generate homogeneous warm brightness temperature scene binary mask over the earth for the intercalibration of microwave imagers. The objective is to identify homogeneous desert scenes as targets in radiometric intercalibration of multisource multisensor systems such as Global Precipitation Measurement (GPM) constellation. In this paper, a method is de...Show More
The Tropical Rainfall Measurements Mission (TRMM) Microwave Imager (TMI), has served as the radiometric transfer standard for the TRMM constellation radiometers for over 17 years. The final legacy processing for the TMI is in progress for the TMI 1B11 Tb Version-8 (V8), which will be released in late 2017. This paper presents a radiometric evaluation of the Tb differences between the current TMI V...Show More
The TRMM Microwave Imager has provided a nearly two-decade satellite remote sensing data set for studying climate change, and the legacy data processing is in progress and will be released in late 2017. During this reprocessing, it was discovered that the hot-load suffers an occasional transient solar intrusion, which resulted in a small systematic brightness temperature error. This paper describe...Show More
This paper outlines a technical approach to generate homogeneous warm scene binary mask: SHOWmask using microwave radiometer observations. The objective is to identify homogeneous desert scenes as targets in radiometric intercalibration of multi source multi-sensor systems. In the current paper a method is developed to generate mask on continental Australia using 10 GHz and 18 GHz Vertical and Hor...Show More
This paper concerns the measurement of brightness temperature using the TRMM Microwave Imager (TMI) satellite microwave radiometer. Specifically, the development of an algorithm for correcting the effects of a slightly emissive reflector antenna on the measured earth scene radiance is presented. This algorithm is based upon rigorous radiative transfer theory and on-orbit reflector emissivity measu...Show More
Based upon research with the Aquarius (AQ) satellite remote sensor, a rain impact model (RIM) has been developed which estimates the occurrence of sea surface salinity (SSS) stratification. RIM uses global salinity (HYCOM) and rainfall (CMORPH) products to estimate the transient change in SSS due to rainfall. Previously SSS predicted by RIM have exhibited good correlations with AQ, but the choice ...Show More
This paper deals with the analysis of remote sensing experiments conducted for the purpose of estimating microwave rain extinction coefficients in intense convective rain events. Because the sensors (NEXRAD, zenith looking radiometer and in-situ rain gauge/disdrometer) sample different portions of the rain column they cannot be compared directly in the time domain. To account for these differences...Show More
The Hurricane Imaging Radiometer (HIRAD) is an airborne microwave radiometer developed to provide wide-swath hurricane surface wind speed and rain rate imagery for scientific research. This letter presents a geometric evaluation of the brightness temperature (Tb) images produced by HIRAD for high-contrast land/water targets. Methodologies used to validate geolocation accuracy and spatial resolutio...Show More
This paper discusses the radiometric calibration of millimeter sounder radiometers, on polar orbiter satellites in the NASA Global Precipitation Mission (GPM) constellation; and presents radiometric bias results. Because the Tropical Rainfall Measurement Mission (TRMM) operated for over 17 years, it is important to combine the TRMM and the GPM precipitation datasets to produce a climate data recor...Show More