Textile Diamond Dipole and Artificial Magnetic Conductor Performance under Bending, Wetness and Specific Absorption Rate Measurements

Textile diamond dipole and Artificial Magnetic Conductor (AMC) have been proposed and tested under wearable and body centric measurements. The proposed antenna and AMC sheet are entirely made of textiles for both the substrate and conducting parts, thus making it suitable for wearable communications. Directive radiation patterns with high gain are obtained with the proposed AMC sheet, hence minimizing the radiation towards the human body. In this study, wearable and body centric measurements are investigated which include bending, wetness and Specific Absorption Rate (SAR). Bending is found not to give significant effect to the antenna and AMC performance, as opposed to wetness that yields severe performance distortion. However, the original performance is retrieved once the antenna and AMC dried. Moreover, notable SAR reduction is achieved with the introduction of the AMC sheet, which is appropriate to reduce the radiation that penetrates into human flesh

Radar systems for the water resources mission, volume 1

The state of the art determination was made for radar measurement of: soil moisture, snow, standing and flowing water, lake and river ice, determination of required spacecraft radar parameters, study of synthetic-aperture radar systems to meet these parametric requirements, and study of techniques for on-board processing of the radar data. Significant new concepts developed include the following: scanning synthetic-aperture radar to achieve wide-swath coverage; single-sideband radar; and comb-filter range-sequential, range-offset SAR processing. The state of the art in radar measurement of water resources parameters is outlined. The feasibility for immediate development of a spacecraft water resources SAR was established. Numerous candidates for the on-board processor were examined

レーダー・クロス・セクションを用いた円柱形状物質内の水分量推定に関する研究

早大学位記番号:新7736早稲田大

Measurement of snowpack properties using active FM-CW microwave systems

1982 Summer.Includes bibliographical references.This paper reports on the use of an FM-CW active microwave system, in a research mode, to remotely sense water equivalence and liquid water content of snowpacks. A three-component "electrical path length" dielectric mixture model is described which accounts for the microwave system response as a function of operating frequency, snow density and depth (water equivalence), and liquid water content. This physically based model is compared to currently accepted, semi-empirical mixture models and the limited data that exists. The "electrical path length" model compares favorably and has a distinctly simpler form than other models, making it workable for the specific problem addressed. It is concluded that by collecting data in two frequency ranges (just below the relaxation frequency of water), the depth of ice, the depth of liquid water, and thus the water equivalence of dry or wet snowpacks could be determined. Liquid water content determinations, made on a real-time basis, could then serve as invaluable melt-rate indexes for remote sites. Recommendations are given for the design configuration of an operational system, which could be incorporated into hydrometeorological data acquisition platforms such as SNOTEL