scholarly journals Seasonal Distribution of the Radio Wave Refraction Index over the Territory of Buryatia

2022 ◽  
Vol 16 (2) ◽  
pp. 5-13
Author(s):  
A. S. Bazarova ◽  
R. S. Sychev ◽  
A. V. Bazarov ◽  
E. B. Atutov ◽  
Yu. B. Bashkuev
Keyword(s):  
Refractive Index ◽  
Radio Wave ◽  
Lake Baikal ◽  
Refraction Index ◽  
Seasonal Distribution ◽  
Radio Waves ◽  
Atmospheric Refraction ◽  
Wave Refraction ◽  
Monthly Average ◽  
Main Maximum

The values of the atmospheric refraction index N for ultra-short radio waves for the territory of Buryatia according to the data of meteorological stations were calculated. The monthly average values N contours maps for the central months of the seasons of 2020 were constructed. It is shown the humidity of Lake Baikal and the relief significantly influence N. On average, the values of the refractive index near the lake are 20–30 N-units higher. It is revealed the monthly average N values have maxima in winter and summer with minimums in spring and autumn, with the main maximum occurring in July.

scholarly journals Determining Weather Radar Antenna Pointing Using Signals Detected from the Sun at Low Antenna Elevations

2007 ◽  
Vol 24 (3) ◽  
pp. 476-483 ◽  
Author(s):  
Asko Huuskonen ◽  
Iwan Holleman
Keyword(s):  
Relative Humidity ◽  
Radio Wave ◽  
Simplified Model ◽  
The Sun ◽  
Radio Waves ◽  
Atmospheric Attenuation ◽  
Atmospheric Refraction ◽  
Finnish Meteorological Institute ◽  
Radar Antenna ◽  
Meteorological Institute

Abstract A method to determine the elevation and azimuth biases of the radar antenna using solar signals observed by a scanning radar is presented. Data recorded at low elevation angles where the atmospheric refraction has a significant effect on the propagation of the radio wave are used, and a method to take the effect of the refraction into account in the analysis is presented. A set of equations is given by which the refraction of the radio waves as a function of the relative humidity can easily be calculated. Also, a simplified model for the calculation of the atmospheric attenuation is presented. The consistency of the adopted models for the atmospheric refraction and atmospheric attenuation is confirmed by data collected at a single elevation pointing, but over a long observing time. Finally, the method is applied to datasets based on operational measurements at the Finnish Meteorological Institute (FMI) and Royal Netherlands Meteorological Institute (KNMI), and elevation and azimuth biases of the radars are shown.

Light Capacitance Type Refractometer to Measure Atmosphere Parameter

2013 ◽  
Vol 367 ◽  
pp. 297-301
Author(s):  
Tao Guo ◽  
Zeng Ping Liu
Keyword(s):  
Refractive Index ◽  
Refraction Index ◽  
High Accuracy ◽  
Accurate Estimate ◽  
Light Weight ◽  
Key Factors ◽  
Atmospheric Refraction ◽  
Precise Measure ◽  
Measure Error ◽  
Better Than

The precise measure of atmospheric refractive index is one of the key factors which leads a guarantee of accurate estimate in the atmospheric refraction error margin and the forecast of atmosphere wave in the electronics systems, such as radar and correspondence...etc.. The error of 59 radiosonde which are in common used to measure atmospheric refractive refraction index is bigger, the microwave refract meter which has high accuracy also has the characteristics of high expenses, big weight of the instrument, those all bring very big restriction to engineering physically applications. For this cause, according to the principle that the variety of atmospheric refractive index brings frequency to the LC shock loop which composed by fixed inductance and air capacitor, this paper designs a light capacitance type refract meter which is use low temperature degree coefficient air capacitor for measure of sensitive component. Experiment validated: The precision of light capacitance type refract meter is more better than 59 radiosonde in measuring atmospheric refractive index, and it has no space-time measure error when sending out the temperature, wet, pressure respectively which is common find in 59 radiosonde, and it has advantages like light weight, small lag coefficient etc.

scholarly journals Sensing Framework for the Internet of Actors in the Value Co-Creation Process with a Beacon-Attachable Indoor Positioning System

Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 83
Author(s):  
Keiichi Zempo ◽  
Taiga Arai ◽  
Takuya Aoki ◽  
Yukihiko Okada
Keyword(s):  
Radio Wave ◽  
Indoor Positioning ◽  
Measurement Range ◽  
Pulse Interval ◽  
Retail Stores ◽  
Positioning System ◽  
Radio Waves ◽  
Positioning Systems ◽  
Environment Recognition ◽  
Indoor Positioning System

To evaluate and improve the value of a service, it is important to measure not only the outcomes, but also the process of the service. Value co-creation (VCC) is not limited to outcomes, especially in interpersonal services based on interactions between actors. In this paper, a sensing framework for a VCC process in retail stores is proposed by improving an environment recognition based indoor positioning system with high positioning performance in a metal shelf environment. The conventional indoor positioning systems use radio waves; therefore, errors are caused by reflection, absorption, and interference from metal shelves. An improvement in positioning performance was achieved in the proposed method by using an IR (infrared) slit and IR light, which avoids such errors. The system was designed to recognize many and unspecified people based on the environment recognition method that the receivers had installed, in the service environment. In addition, sensor networking was also conducted by adding a function to transmit payload and identification simultaneously to the beacons that were attached to positioning objects. The effectiveness of the proposed method was verified by installing it not only in an experimental environment with ideal conditions, but posteriorly, the system was tested in real conditions, in a retail store. In our experimental setup, in a comparison with equal element numbers, positioning identification was possible within an error of 96.2 mm in a static environment in contrast to the radio wave based method where an average positioning error of approximately 648 mm was measured using the radio wave based method (Bluetooth low-energy fingerprinting technique). Moreover, when multiple beacons were used simultaneously in our system within the measurement range of one receiver, the appropriate setting of the pulse interval and jitter rate was implemented by simulation. Additionally, it was confirmed that, in a real scenario, it is possible to measure the changes in movement and positional relationships between people. This result shows the feasibility of measuring and evaluating the VCC process in retail stores, although it was difficult to measure the interaction between actors.

scholarly journals Effects of Atmospheric Refraction on an Airborne Weather Radar Detection and Correction Method

2015 ◽  
Vol 2015 ◽  
pp. 1-8
Author(s):  
Lei Wang ◽  
Ming Wei ◽  
Tao Yang ◽  
Ping Liu
Keyword(s):  
Weather Radar ◽  
Weather Conditions ◽  
Refraction Index ◽  
Correction Method ◽  
Propagation Path ◽  
Radar Detection ◽  
Atmospheric Refraction ◽  
Radar Beam ◽  
Fitting Method ◽  
Flight Parameters

This study investigates the effect of atmospheric refraction, affected by temperature, atmospheric pressure, and humidity, on airborne weather radar beam paths. Using three types of typical atmospheric background sounding data, we established a simulation model for an actual transmission path and a fitted correction path of an airborne weather radar beam during airplane take-offs and landings based on initial flight parameters and X-band airborne phased-array weather radar parameters. Errors in an ideal electromagnetic beam propagation path are much greater than those of a fitted path when atmospheric refraction is not considered. The rates of change in the atmospheric refraction index differ with weather conditions and the radar detection angles differ during airplane take-off and landing. Therefore, the airborne radar detection path must be revised in real time according to the specific sounding data and flight parameters. However, an error analysis indicates that a direct linear-fitting method produces significant errors in a negatively refractive atmosphere; a piecewise-fitting method can be adopted to revise the paths according to the actual atmospheric structure. This study provides researchers and practitioners in the aeronautics and astronautics field with updated information regarding the effect of atmospheric refraction on airborne weather radar detection and correction methods.

scholarly journals Equivalence between positive and negative refractive index materials in electrostatic cloaks

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xingcai Li ◽  
Juan Wang ◽  
Jinghong Zhang
Keyword(s):  
Refractive Index ◽  
Negative Refraction ◽  
Negative Refractive Index ◽  
Analytical Formula ◽  
Refraction Index ◽  
Dielectric Materials ◽  
Static Field ◽  
Colloid Science ◽  
Negative Refraction Index ◽  
Equivalence Relationship

AbstractWe investigate, both theoretically and numerically, the equivalence relationship between the positive and negative refraction index dielectric materials in electrostatic invisibility cloak. We have derived an analytical formula that enables fast calculate the corresponding positive dielectric constant from the negative refraction index material. The numerical results show that the negative refraction index material can be replaced by the positive refractive index materials in the static field cloak. This offers some new viewpoints for designing new sensing systems and devices in physics, colloid science, and engineering applications.

scholarly journals Perspective Ground-based Method for Diagnostics of the Lower Ionosphere and the Neutral Atmosphere

2013 ◽  
Vol 22 (1) ◽  
Author(s):  
N. V. Bakhmetieva ◽  
G. I. Grigoriev ◽  
A. V. Tolmacheva
Keyword(s):  
Radio Wave ◽  
High Power ◽  
Relative Concentration ◽  
Spectral Characteristics ◽  
Lower Ionosphere ◽  
Internal Gravity Waves ◽  
Spatial Period ◽  
Neutral Atmosphere ◽  
Radio Waves ◽  
D Region

AbstractWe present a new perspective ground-based method for diagnostics of the ionosphere and atmosphere parameters. The method uses one of the numerous physical phenomena observed in the ionosphere illuminated by high-power radio waves. It is a generation of the artificial periodic irregularities (APIs) in the ionospheric plasma. The APIs were found while studying the effects of ionospheric high-power HF modification. It was established that the APIs are formed by a standing wave that occurs due to interference between the upwardly radiated radio wave and its reflection off the ionosphere. The API studies are based upon observation of the Bragg backscatter of the pulsed probe radio wave from the artificial periodic structure. Bragg backscatter occurs if the spatial period of the irregularities is equal to half a wavelength of the probe signal. The API techniques makes it possible to obtain the following information: the profiles of electron density from the lower D-region up to the maximum of the F-layer; the irregular structure of the ionosphere including split of the regular E-layer, the sporadic layers; the vertical velocities in the D- and E-regions of the ionosphere; the turbulent velocities, turbulent diffusion coefficients and the turbopause altitude; the neutral temperatures and densities at the E-region altitudes; the parameters of the internal gravity waves and their spectral characteristics; the relative concentration of negative oxygen ions in the D-region. Some new results obtained by the API technique are discussed.

scholarly journals Velocity of radio waves in glaciers as an indicator of their hydrothermal state, structure and regime

1993 ◽  
Vol 39 (132) ◽  
pp. 373-384 ◽  
Author(s):  
Yu. Ya. Macheret ◽  
M. Yu. Moskalevsky ◽  
E.V. Vasilenko
Keyword(s):  
Experimental Data ◽  
Radio Wave ◽  
Water Content ◽  
Low Frequency ◽  
Wide Angle ◽  
Radio Waves ◽  
State Structure ◽  
Mountain Ridge ◽  
Wave Velocities

AbstractThe results of measurements of radio-wave velocities (RWV) by wide-angle reflection (WAR) methods in the temperate Abramov Glacier in the Alai Mountain Ridge and the “two-layered” sub-polar Fridtjovbreen and Hansbreen on Svalbard using a low-frequency (2–13 MHz) radar are considered and discussed. The experimental data obtained and the data from the literature show that the values of RWV could be a good indicator of the hydrothermal state of glaciers. As such, these data enable the identification of cold, temperate and transitional (two-layered) glaciers, and can be used for estimation of the water content in glaciers and changes in the hydrothermal state.

The role of natural E-region plasma turbulence in the enhanced absorption of HF radio waves in the auroral ionosphere:Implications for RF heating of the auroral electrojet

1994 ◽  
Vol 12 (4) ◽  
pp. 316-332 ◽  
Author(s):  
T. R. Robinson
Keyword(s):  
Radio Wave ◽  
Electromagnetic Waves ◽  
Auroral Electrojet ◽  
Radio Waves ◽  
Electrostatic Waves ◽  
Enhanced Absorption ◽  
Heating Effects ◽  
Wave Heating ◽  
Radio Wave Absorption ◽  
E Region

Abstract. Physical processes which affect the absorption of radio waves passing through the auroral E-region when Farley-Buneman irregularities are present are examined. In particular, the question of whether or not it is legitimate to include the anomalous wave-enhanced collision frequency, which has been used successfully to account for the heating effects of Farley-Buneman waves in the auroral E-region, in the usual expression for the radio-wave absorption coefficient is addressed. Effects also considered are those due to wave coupling between electromagnetic waves and high-frequency electrostatic waves in the presence of Farley-Buneman irregularities. The implications for radio-wave heating of the auroral electrojet of these processes are also discussed. In particular, a new theoretical model for calculating the effects of high-power radio-wave heating on the electron temperature in an electrojet containing Farley-Buneman turbulence is presented.

Sign in / Sign up

Export Citation Format

Share Document