The document presents a mathematical model for calculating radio signal attenuation due to rain. The model is based on using spheroid rain drops over a broad frequency range of 3GHz, 5GHz and 10GHz. Numerical simulations were conducted using MATLAB. The results showed that attenuation (path loss) due to rainfall was 75.46% greater than free space attenuation. Additionally, the received power for the rainfall model was 24.61% less than the free space model. The model provides a more accurate calculation of radio signal attenuation compared to existing models that do not account for factors like rainfall.
Tropospheric Scintillation with Rain Attenuation of Ku Band at Tropical RegionTELKOMNIKA JOURNAL
This document summarizes a study on tropospheric scintillation and rain attenuation in the Ku band at tropical regions. The study analyzes experimental measurement data collected over one year in Johor Bahru, Malaysia. The results show that wet scintillation intensity increases linearly with rain attenuation. Probability density functions of wet scintillation intensity were found to be lognormally distributed for different rain attenuation levels. Scintillation amplitude distributions were best fit by normal distributions for low attenuation and logistic distributions for high attenuation. The study provides models for characterizing the relationship between wet scintillation and rain attenuation in tropical regions.
Radar fundamentals introduces key concepts of radar remote sensing. Radar transmits and receives microwave signals to image the Earth's surface. There are two main types of radar systems - Real Aperture Radar (RAR) and Synthetic Aperture Radar (SAR). SAR uses antenna movement to synthesize a larger antenna and achieve higher resolution. Radar backscatter is influenced by system parameters like wavelength, polarization, and incident angle as well as target characteristics such as surface roughness and electrical properties. SAR images provide unique views of the Earth's surface and are important tools for environmental and military applications.
A hybrid algorithm for wave-front corrections applied to satellite-to-ground ...TELKOMNIKA JOURNAL
Laser communications hold accurate data rate for ground satellite links. The laser beam is transmitted through the atmosphere. The clear-air turbulence induces a number of phase distortions that damage wave-front. Adaptive optics (AO) treats wave front correction. The nature of AO systems is iterative; it can be integrated in metaheuristic algorithms such as genetic algorithm (GA). This paper presents improved version of algorithm for wave-front corrections. The improved algorithm is based on genetic algorithm (GA) and adaptive optics approach (OA). It is implemented in a computer simulation model called object-oriented matlab adaptive optics (OOMAO). The optimisation process involves best possible GA parameters as a function of population size, iteration count, and the actuators’ voltage intervals. Results show that the application of GA improves the performance of AO in wave-front corrections and the communication between satellite-to-ground laser links as well.
Interfade Duration Statistics at Ku-band for Satellite Earth Links System in ...TELKOMNIKA JOURNAL
Fade dynamics is one of more important parameters when implementing Fade Mitigation
Techniques (FMTs) to counteract an excessive attenuation that affect satellite communication systems
operating above 10 GHz. The statistics of probable duration between two rain fade namely interfade
duration enables system operator to estimate how long the system will need to recover before the next
outage and assist in designing the FMTs. In this paper, interfade duration statistics have been derived from
one year of slant path attenuation measurements data collected in Equatorial Johor Bahru at 12.2 GHz
with elevation angle of 75.61o. The result had shown the dependency of number of events with attenuation
thresholds. Empirical interfade duration statistics are also obtained and suitable model distribution are
proposed.
This document provides an overview of synthetic aperture radar (SAR). SAR uses motion of a radar antenna mounted on a moving platform to synthesize a large antenna and create high-resolution radar images. It describes the basic principles of SAR, including how successive radar pulses are transmitted and echoes received to build up an image. Applications of SAR include remote sensing, mapping, and monitoring changes over time. Spectral estimation techniques are used to process SAR data and improve resolution. Polarimetry and interferometry are additional SAR techniques. Typical SAR systems are mounted on aircraft or satellites.
The document discusses principles of radar imaging and synthetic aperture radar (SAR). SAR uses signal modulation and range-Doppler processing to achieve high-resolution radar imagery independent of distance to targets. Polarimetric SAR can characterize target scattering properties by measuring the scattering matrix. Interferometric SAR uses two antennas to measure elevation, while differential interferometry detects elevation changes over time for applications like change detection. Emerging techniques include polarimetric interferometry and using polarization signatures to estimate surface tilt and topography.
Systematic Variation of Rain Rate and Radar Reflectivity Relations for Micro ...iosrjce
This document analyzes two years of rainfall measurement data collected using a vertically-pointing micro rain radar located in Akure, Nigeria to develop empirical models relating rain rate and radar reflectivity over different heights. Time series plots of rain events show variations in rain rate with stratiform and convective rain types observed at different heights. Power law relationships between rain rate (R) and radar reflectivity factor (Z) of the form Z = aRb were obtained through regression analysis for stratiform and convective rain, with different coefficients a and b values for each rain type. The relationships were compared to those reported in other studies and show that coefficients can vary between locations due to the dynamic nature of rainfall.
The document summarizes the radar range equation, which relates characteristics of the radar system and target to the signal power received by the radar. It provides the basic form of the equation and then derives and explains each term in detail. Key terms are the transmitted power, antenna gains, wavelength, target radar cross section, range, and losses. Understanding all the terms and their derivation is important for a solid foundation in radar fundamentals and applications like detection theory.
Tropospheric Scintillation with Rain Attenuation of Ku Band at Tropical RegionTELKOMNIKA JOURNAL
This document summarizes a study on tropospheric scintillation and rain attenuation in the Ku band at tropical regions. The study analyzes experimental measurement data collected over one year in Johor Bahru, Malaysia. The results show that wet scintillation intensity increases linearly with rain attenuation. Probability density functions of wet scintillation intensity were found to be lognormally distributed for different rain attenuation levels. Scintillation amplitude distributions were best fit by normal distributions for low attenuation and logistic distributions for high attenuation. The study provides models for characterizing the relationship between wet scintillation and rain attenuation in tropical regions.
Radar fundamentals introduces key concepts of radar remote sensing. Radar transmits and receives microwave signals to image the Earth's surface. There are two main types of radar systems - Real Aperture Radar (RAR) and Synthetic Aperture Radar (SAR). SAR uses antenna movement to synthesize a larger antenna and achieve higher resolution. Radar backscatter is influenced by system parameters like wavelength, polarization, and incident angle as well as target characteristics such as surface roughness and electrical properties. SAR images provide unique views of the Earth's surface and are important tools for environmental and military applications.
A hybrid algorithm for wave-front corrections applied to satellite-to-ground ...TELKOMNIKA JOURNAL
Laser communications hold accurate data rate for ground satellite links. The laser beam is transmitted through the atmosphere. The clear-air turbulence induces a number of phase distortions that damage wave-front. Adaptive optics (AO) treats wave front correction. The nature of AO systems is iterative; it can be integrated in metaheuristic algorithms such as genetic algorithm (GA). This paper presents improved version of algorithm for wave-front corrections. The improved algorithm is based on genetic algorithm (GA) and adaptive optics approach (OA). It is implemented in a computer simulation model called object-oriented matlab adaptive optics (OOMAO). The optimisation process involves best possible GA parameters as a function of population size, iteration count, and the actuators’ voltage intervals. Results show that the application of GA improves the performance of AO in wave-front corrections and the communication between satellite-to-ground laser links as well.
Interfade Duration Statistics at Ku-band for Satellite Earth Links System in ...TELKOMNIKA JOURNAL
Fade dynamics is one of more important parameters when implementing Fade Mitigation
Techniques (FMTs) to counteract an excessive attenuation that affect satellite communication systems
operating above 10 GHz. The statistics of probable duration between two rain fade namely interfade
duration enables system operator to estimate how long the system will need to recover before the next
outage and assist in designing the FMTs. In this paper, interfade duration statistics have been derived from
one year of slant path attenuation measurements data collected in Equatorial Johor Bahru at 12.2 GHz
with elevation angle of 75.61o. The result had shown the dependency of number of events with attenuation
thresholds. Empirical interfade duration statistics are also obtained and suitable model distribution are
proposed.
This document provides an overview of synthetic aperture radar (SAR). SAR uses motion of a radar antenna mounted on a moving platform to synthesize a large antenna and create high-resolution radar images. It describes the basic principles of SAR, including how successive radar pulses are transmitted and echoes received to build up an image. Applications of SAR include remote sensing, mapping, and monitoring changes over time. Spectral estimation techniques are used to process SAR data and improve resolution. Polarimetry and interferometry are additional SAR techniques. Typical SAR systems are mounted on aircraft or satellites.
The document discusses principles of radar imaging and synthetic aperture radar (SAR). SAR uses signal modulation and range-Doppler processing to achieve high-resolution radar imagery independent of distance to targets. Polarimetric SAR can characterize target scattering properties by measuring the scattering matrix. Interferometric SAR uses two antennas to measure elevation, while differential interferometry detects elevation changes over time for applications like change detection. Emerging techniques include polarimetric interferometry and using polarization signatures to estimate surface tilt and topography.
Systematic Variation of Rain Rate and Radar Reflectivity Relations for Micro ...iosrjce
This document analyzes two years of rainfall measurement data collected using a vertically-pointing micro rain radar located in Akure, Nigeria to develop empirical models relating rain rate and radar reflectivity over different heights. Time series plots of rain events show variations in rain rate with stratiform and convective rain types observed at different heights. Power law relationships between rain rate (R) and radar reflectivity factor (Z) of the form Z = aRb were obtained through regression analysis for stratiform and convective rain, with different coefficients a and b values for each rain type. The relationships were compared to those reported in other studies and show that coefficients can vary between locations due to the dynamic nature of rainfall.
The document summarizes the radar range equation, which relates characteristics of the radar system and target to the signal power received by the radar. It provides the basic form of the equation and then derives and explains each term in detail. Key terms are the transmitted power, antenna gains, wavelength, target radar cross section, range, and losses. Understanding all the terms and their derivation is important for a solid foundation in radar fundamentals and applications like detection theory.
The document discusses various propagation mechanisms that affect radio signals, including reflection, diffraction, scattering, and their effects on signal strength over distance. It also covers propagation models like free space path loss, two-ray ground reflection model, and log-distance path loss for estimating average received signal power at a given distance. Fresnel zones and knife-edge diffraction are explained as factors in signal propagation around obstructions. Log-normal shadowing is described as a statistical model to account for variations from the average path loss.
The document summarizes the observation of gravitational waves from a binary black hole merger detected by the LIGO detectors on September 14, 2015. The key points are:
1) LIGO detected a transient gravitational-wave signal that matches predictions from general relativity for the inspiral and merger of two black holes.
2) Analysis of the signal determines that the initial black hole masses were about 36 and 29 solar masses, which merged into a final black hole of about 62 solar masses over 0.2 seconds.
3) This is the first direct detection of gravitational waves as well as the first observation of a binary black hole merger, confirming predictions from Einstein's theory of general relativity.
Radar works by sending out pulses of energy and measuring the return signal, or backscatter. The strength of the returned signal depends on characteristics of the targets such as size, shape, and concentration. Radar is used to estimate precipitation by relating the measured reflectivity to rainfall rate, though there are limitations since the actual drop size distribution is not known. Doppler radar additionally measures the radial velocity of targets by detecting changes in frequency of the returned signal from the Doppler effect. Managing the pulse repetition frequency allows tradeoffs between maximum unambiguous range and velocity but can cause ambiguities like range folding if not properly adjusted.
WE3.L09 - RAIN EFFECT ON POLARIMETRIC SAR OBSERVATIONgrssieee
The document evaluates the quantitative effects of rain on polarimetric synthetic aperture radar (SAR) observation. It presents a SAR observation model and estimates rain-induced attenuation, attenuation ratios between polarizations, and depolarization for different rain rates, frequencies, incidence angles, and drop canting angles. The results show that rain effects increase with frequency, rain rate, and canting angle. The document concludes that rain significantly impacts polarimetric SAR observation in ways that depend on these experimental conditions.
Multi-Resolution Analysis: MRA Based Bright Band Height Estimation with Preci...Waqas Tariq
A method for reconstruction of cross section of rainfall situations with precipitation radar data based on wavelet analysis of Multi-Resolution Analysis (MRA) which allows extract a peak of the radar reflectivity is proposed in order to detect bright band height. It is found that the bright band height can be estimated by using the MRA with the basis of Daubechies wavelet family. It is also found that the boundaries in rainfall structure can be clearly extracted with MRA.
This document summarizes a research paper on using discrete wavelet transform (DWT) and empirical mode decomposition (EMD) to remove "ghosting effects" from seismic signals. It begins with an introduction to earthquakes and how they are recorded via seismographs. It then describes existing filtering methods and their limitations. The proposed method uses 1D convolutional filtering and vibration analysis with DWT and EMD to enhance noisy seismic wave signals. It involves steps like magnitude spectrum estimation, windowing, phase estimation, noise variance prediction, and directional estimation. The method is able to attenuate coherent noise and improve seismic wave detection, separation and tracking. In conclusion, time-scale directional filters are a powerful tool for seismic data
Estimation of Water Vapour Attenuation And Rain AttenuationIJERA Editor
Attenuation due to and water vapour and rain can severely degrade the radio wave propagation at centimeter or millimeter wavelengths. It restricts the path length of radio communication systems and limits the use of higher frequencies for line-of-sight microwave links and satellite communications. The attenuation will pose a greater problem to communication as the frequency of occurrence of heavy rain increases.In a tropical region, like Malaysia, where excessive rainfall is a common phenomenon throughout the year, the knowledge of the rain attenuation at the frequency of operation is extremely required for the design of a reliable terrestrial and earth space communication link at a particular location.
This document discusses models for predicting path loss of sky wave and ground wave propagation in the HF frequency range. It recommends using the ICEPAC program from the IONCAP family to predict sky wave propagation path loss, as it is the most advanced model and has been effectively used for frequency planning. For ground wave propagation prediction, it discusses different models available and the factors that influence path loss, such as ground conductivity.
Diurnal Effects on Satellite Network Performance Measured In Tropical RegionIOSR Journals
This document analyzes the diurnal effects on satellite network performance in tropical regions. It describes how the signal strength of a DTH (direct-to-home) broadcasting service varies throughout the day due to changes in temperature, humidity, cloud cover and other atmospheric conditions. The study recorded signal strength data from a DTH antenna in Dombivli, India over the month of February. It found that signal strength was generally better in mornings and evenings when temperatures were lower, but dropped in afternoons as temperatures increased, likely due to changes in atmospheric refractivity affecting signal propagation. Understanding these diurnal variations can help improve the availability and quality of service for DTH broadcasting customers.
This document discusses the history and development of radar technology. It begins with early experiments with radio waves in the late 1800s by scientists like Hertz, Hulsmeyer and Tesla. It then outlines key developments in radar including the first demonstration of detecting aircraft using radio echoes in 1935 by Watson-Watt and Wilkins. The document also discusses the basic components and operating principles of radar systems including antennas, transmitters, receivers and data processors. It provides examples of converting between decimal, binary, octal and hexadecimal number systems.
Error Performance Analysis in Underwater Acoustic Noise with Non-Gaussian Dis...TELKOMNIKA JOURNAL
1) The document analyzes error performance in underwater acoustic noise channels with non-Gaussian distributions. Field data was collected off the coast of Malaysia and found to follow a Student's t distribution rather than Gaussian.
2) A probability density function for the noise amplitude is proposed based on the Student's t distribution. An expression for binary error probability is derived considering the non-Gaussian noise characteristics.
3) Simulations show the underwater acoustic noise channel has slightly better error performance than Gaussian noise channels at low SNR, but significantly worse performance at high SNR, due to the shape of the Student's t distribution. The non-Gaussian noise degrades performance more for higher order modulations.
This document summarizes the development of gravitational wave detection and possible sources. It discusses James Weber's early experiments using aluminum bar detectors in the 1960s, which reported the first detections of gravitational waves. It also describes proposals to use laser interferometers and resonant bar detectors, which could achieve greater sensitivity. Finally, it outlines potential sources of gravitational waves including bursts from stellar collapses and mergers, and continuous waves from rapidly spinning neutron stars.
This document presents a method for deriving equations to model the operation of a bistatic tracking radar (BTR) system. A BTR uses separate transmitter and receiver stations to detect and track targets. The document:
1) Uses triangulation geometry to model the positions and angles between the transmitter, receiver, and target.
2) Derives equations to calculate distances and antenna angles/directions based on initial target data and the propagation time delay.
3) Explains how the BTR system would use these equations to continuously track a maneuvering target by adjusting the transmitter antenna position based on receiver measurements and commands.
4) Presents simulation results validating the derived BTR modeling equations and tracking algorithm.
Terrestrial microwave communication uses high-frequency radio waves to transmit data between two fixed points using antennas with a direct line-of-sight. It operates between 2-60 GHz and requires repeaters for long distances. Key advantages are fast deployment, flexibility, and ability to link across obstacles. Design considerations include ensuring the Fresnel zone around the beam path is clear of obstacles to minimize signal diffraction and interference. Link budgets calculate total gains and losses to determine maximum transmission distances.
This document provides an overview of radar principles and technologies. It discusses the different radar frequency bands and power levels used. It then describes the basic components and functioning of pulsed radar systems, including how radar range is calculated from the time it takes a pulse to travel to a target and return. Continuous wave and pulse radar are the two main types discussed, along with Doppler radar. Factors influencing maximum radar range are also covered through the radar range equation.
An Extended Tropospheric Scintillation Model for Free Space Optical Communica...ijeei-iaes
Fluctuations caused mostly by tropospheric scintillation at the free space optical receiver end have been a major problem in the rapid development of telecommunication and the increasing demands for larger bandwidth is forcing the use of free space optical (FSO) technology. This paper examined existing tropospheric scintillation models of Karasawa, Van de Kamp model, Otung, Ortgies and ITU-R, and discovered that all of them operate at the microwave range, which limits their application in FSO laser beam technology that operates in PHz frequency-range. ITU-R model was later selected owing to its global application and modified for use in FSO communication system. The new model can serve as basis for communication engineers to use as platform in the link budgetary for planning and design of low margin systems of free space optical communication link.
This document provides an overview of key concepts in antennas and propagation. It defines an antenna as a device that transmits or receives electromagnetic waves. It describes common antenna types like dipoles and parabolic reflectors. It also covers topics like radiation patterns, antenna gain, propagation modes (ground wave, sky wave, line-of-sight), free space loss, noise, multipath, and techniques to mitigate signal degradation like diversity and error correction.
This document discusses how Interferometric Synthetic Aperture Radar (InSAR) works to measure ground deformation. It explains that InSAR uses the phase difference between two SAR images of the same area taken at different times to detect millimeter-scale changes in the distance to ground targets. It provides examples of how InSAR has been used to measure subsidence from earthquakes and other natural hazards. The document also notes some limitations of InSAR related to decorrelation from changes on the ground surface and in the atmosphere between image acquisitions.
Stationary waves and slowly moving features in the night upper clouds of VenusSérgio Sacani
This document summarizes observations of nightside cloud features in Venus' upper atmosphere made using infrared imaging from the Venus Express spacecraft and ground-based telescopes. Three types of cloud features were observed: 1) Nearly stationary wave patterns with speeds of -10 to +10 m/s, 2) Fast moving filaments and shear-like features with speeds consistent with the daytime cloud tops, and 3) Variable speed patchy features with speeds ranging from -100 to -50 m/s and some moving more slowly. Radiative transfer modeling indicates the features observed in infrared wavelengths of 3.8 and 5.0 μm originate between altitudes of 60-72 km.
A time series analysis of the determinants of savings in namibiaAlexander Decker
This document summarizes a study on the determinants of savings in Namibia from 1991 to 2012. It reviews previous literature on savings determinants in developing countries. The study uses time series analysis including unit root tests, cointegration, and error correction models to analyze the relationship between savings and variables like income, inflation, population growth, deposit rates, and financial deepening in Namibia. The results found inflation and income have a positive impact on savings, while population growth negatively impacts savings. Deposit rates and financial deepening were found to have no significant impact. The study reinforces previous work and emphasizes the importance of improving income levels to achieve higher savings rates in Namibia.
A transformational generative approach towards understanding al-istifhamAlexander Decker
This document discusses a transformational-generative approach to understanding Al-Istifham, which refers to interrogative sentences in Arabic. It begins with an introduction to the origin and development of Arabic grammar. The paper then explains the theoretical framework of transformational-generative grammar that is used. Basic linguistic concepts and terms related to Arabic grammar are defined. The document analyzes how interrogative sentences in Arabic can be derived and transformed via tools from transformational-generative grammar, categorizing Al-Istifham into linguistic and literary questions.
The document discusses various propagation mechanisms that affect radio signals, including reflection, diffraction, scattering, and their effects on signal strength over distance. It also covers propagation models like free space path loss, two-ray ground reflection model, and log-distance path loss for estimating average received signal power at a given distance. Fresnel zones and knife-edge diffraction are explained as factors in signal propagation around obstructions. Log-normal shadowing is described as a statistical model to account for variations from the average path loss.
The document summarizes the observation of gravitational waves from a binary black hole merger detected by the LIGO detectors on September 14, 2015. The key points are:
1) LIGO detected a transient gravitational-wave signal that matches predictions from general relativity for the inspiral and merger of two black holes.
2) Analysis of the signal determines that the initial black hole masses were about 36 and 29 solar masses, which merged into a final black hole of about 62 solar masses over 0.2 seconds.
3) This is the first direct detection of gravitational waves as well as the first observation of a binary black hole merger, confirming predictions from Einstein's theory of general relativity.
Radar works by sending out pulses of energy and measuring the return signal, or backscatter. The strength of the returned signal depends on characteristics of the targets such as size, shape, and concentration. Radar is used to estimate precipitation by relating the measured reflectivity to rainfall rate, though there are limitations since the actual drop size distribution is not known. Doppler radar additionally measures the radial velocity of targets by detecting changes in frequency of the returned signal from the Doppler effect. Managing the pulse repetition frequency allows tradeoffs between maximum unambiguous range and velocity but can cause ambiguities like range folding if not properly adjusted.
WE3.L09 - RAIN EFFECT ON POLARIMETRIC SAR OBSERVATIONgrssieee
The document evaluates the quantitative effects of rain on polarimetric synthetic aperture radar (SAR) observation. It presents a SAR observation model and estimates rain-induced attenuation, attenuation ratios between polarizations, and depolarization for different rain rates, frequencies, incidence angles, and drop canting angles. The results show that rain effects increase with frequency, rain rate, and canting angle. The document concludes that rain significantly impacts polarimetric SAR observation in ways that depend on these experimental conditions.
Multi-Resolution Analysis: MRA Based Bright Band Height Estimation with Preci...Waqas Tariq
A method for reconstruction of cross section of rainfall situations with precipitation radar data based on wavelet analysis of Multi-Resolution Analysis (MRA) which allows extract a peak of the radar reflectivity is proposed in order to detect bright band height. It is found that the bright band height can be estimated by using the MRA with the basis of Daubechies wavelet family. It is also found that the boundaries in rainfall structure can be clearly extracted with MRA.
This document summarizes a research paper on using discrete wavelet transform (DWT) and empirical mode decomposition (EMD) to remove "ghosting effects" from seismic signals. It begins with an introduction to earthquakes and how they are recorded via seismographs. It then describes existing filtering methods and their limitations. The proposed method uses 1D convolutional filtering and vibration analysis with DWT and EMD to enhance noisy seismic wave signals. It involves steps like magnitude spectrum estimation, windowing, phase estimation, noise variance prediction, and directional estimation. The method is able to attenuate coherent noise and improve seismic wave detection, separation and tracking. In conclusion, time-scale directional filters are a powerful tool for seismic data
Estimation of Water Vapour Attenuation And Rain AttenuationIJERA Editor
Attenuation due to and water vapour and rain can severely degrade the radio wave propagation at centimeter or millimeter wavelengths. It restricts the path length of radio communication systems and limits the use of higher frequencies for line-of-sight microwave links and satellite communications. The attenuation will pose a greater problem to communication as the frequency of occurrence of heavy rain increases.In a tropical region, like Malaysia, where excessive rainfall is a common phenomenon throughout the year, the knowledge of the rain attenuation at the frequency of operation is extremely required for the design of a reliable terrestrial and earth space communication link at a particular location.
This document discusses models for predicting path loss of sky wave and ground wave propagation in the HF frequency range. It recommends using the ICEPAC program from the IONCAP family to predict sky wave propagation path loss, as it is the most advanced model and has been effectively used for frequency planning. For ground wave propagation prediction, it discusses different models available and the factors that influence path loss, such as ground conductivity.
Diurnal Effects on Satellite Network Performance Measured In Tropical RegionIOSR Journals
This document analyzes the diurnal effects on satellite network performance in tropical regions. It describes how the signal strength of a DTH (direct-to-home) broadcasting service varies throughout the day due to changes in temperature, humidity, cloud cover and other atmospheric conditions. The study recorded signal strength data from a DTH antenna in Dombivli, India over the month of February. It found that signal strength was generally better in mornings and evenings when temperatures were lower, but dropped in afternoons as temperatures increased, likely due to changes in atmospheric refractivity affecting signal propagation. Understanding these diurnal variations can help improve the availability and quality of service for DTH broadcasting customers.
This document discusses the history and development of radar technology. It begins with early experiments with radio waves in the late 1800s by scientists like Hertz, Hulsmeyer and Tesla. It then outlines key developments in radar including the first demonstration of detecting aircraft using radio echoes in 1935 by Watson-Watt and Wilkins. The document also discusses the basic components and operating principles of radar systems including antennas, transmitters, receivers and data processors. It provides examples of converting between decimal, binary, octal and hexadecimal number systems.
Error Performance Analysis in Underwater Acoustic Noise with Non-Gaussian Dis...TELKOMNIKA JOURNAL
1) The document analyzes error performance in underwater acoustic noise channels with non-Gaussian distributions. Field data was collected off the coast of Malaysia and found to follow a Student's t distribution rather than Gaussian.
2) A probability density function for the noise amplitude is proposed based on the Student's t distribution. An expression for binary error probability is derived considering the non-Gaussian noise characteristics.
3) Simulations show the underwater acoustic noise channel has slightly better error performance than Gaussian noise channels at low SNR, but significantly worse performance at high SNR, due to the shape of the Student's t distribution. The non-Gaussian noise degrades performance more for higher order modulations.
This document summarizes the development of gravitational wave detection and possible sources. It discusses James Weber's early experiments using aluminum bar detectors in the 1960s, which reported the first detections of gravitational waves. It also describes proposals to use laser interferometers and resonant bar detectors, which could achieve greater sensitivity. Finally, it outlines potential sources of gravitational waves including bursts from stellar collapses and mergers, and continuous waves from rapidly spinning neutron stars.
This document presents a method for deriving equations to model the operation of a bistatic tracking radar (BTR) system. A BTR uses separate transmitter and receiver stations to detect and track targets. The document:
1) Uses triangulation geometry to model the positions and angles between the transmitter, receiver, and target.
2) Derives equations to calculate distances and antenna angles/directions based on initial target data and the propagation time delay.
3) Explains how the BTR system would use these equations to continuously track a maneuvering target by adjusting the transmitter antenna position based on receiver measurements and commands.
4) Presents simulation results validating the derived BTR modeling equations and tracking algorithm.
Terrestrial microwave communication uses high-frequency radio waves to transmit data between two fixed points using antennas with a direct line-of-sight. It operates between 2-60 GHz and requires repeaters for long distances. Key advantages are fast deployment, flexibility, and ability to link across obstacles. Design considerations include ensuring the Fresnel zone around the beam path is clear of obstacles to minimize signal diffraction and interference. Link budgets calculate total gains and losses to determine maximum transmission distances.
This document provides an overview of radar principles and technologies. It discusses the different radar frequency bands and power levels used. It then describes the basic components and functioning of pulsed radar systems, including how radar range is calculated from the time it takes a pulse to travel to a target and return. Continuous wave and pulse radar are the two main types discussed, along with Doppler radar. Factors influencing maximum radar range are also covered through the radar range equation.
An Extended Tropospheric Scintillation Model for Free Space Optical Communica...ijeei-iaes
Fluctuations caused mostly by tropospheric scintillation at the free space optical receiver end have been a major problem in the rapid development of telecommunication and the increasing demands for larger bandwidth is forcing the use of free space optical (FSO) technology. This paper examined existing tropospheric scintillation models of Karasawa, Van de Kamp model, Otung, Ortgies and ITU-R, and discovered that all of them operate at the microwave range, which limits their application in FSO laser beam technology that operates in PHz frequency-range. ITU-R model was later selected owing to its global application and modified for use in FSO communication system. The new model can serve as basis for communication engineers to use as platform in the link budgetary for planning and design of low margin systems of free space optical communication link.
This document provides an overview of key concepts in antennas and propagation. It defines an antenna as a device that transmits or receives electromagnetic waves. It describes common antenna types like dipoles and parabolic reflectors. It also covers topics like radiation patterns, antenna gain, propagation modes (ground wave, sky wave, line-of-sight), free space loss, noise, multipath, and techniques to mitigate signal degradation like diversity and error correction.
This document discusses how Interferometric Synthetic Aperture Radar (InSAR) works to measure ground deformation. It explains that InSAR uses the phase difference between two SAR images of the same area taken at different times to detect millimeter-scale changes in the distance to ground targets. It provides examples of how InSAR has been used to measure subsidence from earthquakes and other natural hazards. The document also notes some limitations of InSAR related to decorrelation from changes on the ground surface and in the atmosphere between image acquisitions.
Stationary waves and slowly moving features in the night upper clouds of VenusSérgio Sacani
This document summarizes observations of nightside cloud features in Venus' upper atmosphere made using infrared imaging from the Venus Express spacecraft and ground-based telescopes. Three types of cloud features were observed: 1) Nearly stationary wave patterns with speeds of -10 to +10 m/s, 2) Fast moving filaments and shear-like features with speeds consistent with the daytime cloud tops, and 3) Variable speed patchy features with speeds ranging from -100 to -50 m/s and some moving more slowly. Radiative transfer modeling indicates the features observed in infrared wavelengths of 3.8 and 5.0 μm originate between altitudes of 60-72 km.
A time series analysis of the determinants of savings in namibiaAlexander Decker
This document summarizes a study on the determinants of savings in Namibia from 1991 to 2012. It reviews previous literature on savings determinants in developing countries. The study uses time series analysis including unit root tests, cointegration, and error correction models to analyze the relationship between savings and variables like income, inflation, population growth, deposit rates, and financial deepening in Namibia. The results found inflation and income have a positive impact on savings, while population growth negatively impacts savings. Deposit rates and financial deepening were found to have no significant impact. The study reinforces previous work and emphasizes the importance of improving income levels to achieve higher savings rates in Namibia.
A transformational generative approach towards understanding al-istifhamAlexander Decker
This document discusses a transformational-generative approach to understanding Al-Istifham, which refers to interrogative sentences in Arabic. It begins with an introduction to the origin and development of Arabic grammar. The paper then explains the theoretical framework of transformational-generative grammar that is used. Basic linguistic concepts and terms related to Arabic grammar are defined. The document analyzes how interrogative sentences in Arabic can be derived and transformed via tools from transformational-generative grammar, categorizing Al-Istifham into linguistic and literary questions.
A trends of salmonella and antibiotic resistanceAlexander Decker
This document provides a review of trends in Salmonella and antibiotic resistance. It begins with an introduction to Salmonella as a facultative anaerobe that causes nontyphoidal salmonellosis. The emergence of antimicrobial-resistant Salmonella is then discussed. The document proceeds to cover the historical perspective and classification of Salmonella, definitions of antimicrobials and antibiotic resistance, and mechanisms of antibiotic resistance in Salmonella including modification or destruction of antimicrobial agents, efflux pumps, modification of antibiotic targets, and decreased membrane permeability. Specific resistance mechanisms are discussed for several classes of antimicrobials.
A unique common fixed point theorems in generalized dAlexander Decker
This document presents definitions and properties related to generalized D*-metric spaces and establishes some common fixed point theorems for contractive type mappings in these spaces. It begins by introducing D*-metric spaces and generalized D*-metric spaces, defines concepts like convergence and Cauchy sequences. It presents lemmas showing the uniqueness of limits in these spaces and the equivalence of different definitions of convergence. The goal of the paper is then stated as obtaining a unique common fixed point theorem for generalized D*-metric spaces.
A universal model for managing the marketing executives in nigerian banksAlexander Decker
This document discusses a study that aimed to synthesize motivation theories into a universal model for managing marketing executives in Nigerian banks. The study was guided by Maslow and McGregor's theories. A sample of 303 marketing executives was used. The results showed that managers will be most effective at motivating marketing executives if they consider individual needs and create challenging but attainable goals. The emerged model suggests managers should provide job satisfaction by tailoring assignments to abilities and monitoring performance with feedback. This addresses confusion faced by Nigerian bank managers in determining effective motivation strategies.
A usability evaluation framework for b2 c e commerce websitesAlexander Decker
This document presents a framework for evaluating the usability of B2C e-commerce websites. It involves user testing methods like usability testing and interviews to identify usability problems in areas like navigation, design, purchasing processes, and customer service. The framework specifies goals for the evaluation, determines which website aspects to evaluate, and identifies target users. It then describes collecting data through user testing and analyzing the results to identify usability problems and suggest improvements.
Abnormalities of hormones and inflammatory cytokines in women affected with p...Alexander Decker
Women with polycystic ovary syndrome (PCOS) have elevated levels of hormones like luteinizing hormone and testosterone, as well as higher levels of insulin and insulin resistance compared to healthy women. They also have increased levels of inflammatory markers like C-reactive protein, interleukin-6, and leptin. This study found these abnormalities in the hormones and inflammatory cytokines of women with PCOS ages 23-40, indicating that hormone imbalances associated with insulin resistance and elevated inflammatory markers may worsen infertility in women with PCOS.
International Journal of Research in Engineering and Science is an open access peer-reviewed international forum for scientists involved in research to publish quality and refereed papers. Papers reporting original research or experimentally proved review work are welcome. Papers for publication are selected through peer review to ensure originality, relevance, and readability.
The document discusses satellite communication links, including:
- Design of satellite links, which follow free-space propagation and are affected by factors like rain attenuation.
- Link budgets and their interpretation, which use decibel calculations to account for gains and losses across transmitting, receiving, and atmospheric elements.
- Multiple access systems and frequency band trade-offs that satellite communication must consider.
The document discusses satellite communication links, including:
1) The design of satellite links, which involves line-of-sight transmission between earth stations and satellites governed by free-space propagation and atmospheric effects.
2) Link budgets and their interpretation, which quantify gains and losses across transmitter, receiver, and propagation to determine overall carrier-to-noise ratio and performance.
3) Multiple access systems and frequency band trade-offs used for satellite communication.
Estimation of satellite link’s fade margin using non-meteorological techniqu...IJECEIAES
Satellite technology is shifting to higher frequencies such as Q or V-band to cater to greater bandwidth and higher data rates applications such as videoconferencing, internet of things (IoT) and telemedicine. The main challenge in deploying high-frequency bands in heavy precipitation areas is severe rain attenuation. In this paper, a frequency scaling technique was developed to estimate the fade margin at a higher frequency. The worst month analysis was also conducted since the analysis is also important in determining dependable fade margin. The result was evaluated and analyzed using root mean square error (RMSE) and percentage error. The proposed model offers the smallest RMSE and lowest percentage error when compared to all existing prediction models. A dependable fade margin acquired from high-accuracy rain attenuation estimation is very important. This is to apply the best mitigation technique in overcoming rain attenuation in the satellite-Earth link so that, the best system performance can be delivered.
The Aerial Wetted Path of Geostationary Transmissionijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
The Aerial Wetted Path of Geostationary Transmissionijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
A methodology for precise estimation of rain attenuation on terrestrial milli...TELKOMNIKA JOURNAL
This document presents a methodology for precisely estimating rain attenuation on terrestrial millimeter wave links from raindrop size distribution measurements. Rain-induced attenuation is a major impairment for millimeter wave systems. Modern instruments can provide detailed raindrop size distribution measurements, which can be used to estimate their effects on link measurements. The study uses measurements from two links operating at 26GHz and 38GHz in Malaysia along with raindrop size distribution data from a co-located disdrometer. The raindrop size distribution data is used to estimate rain attenuation, which provides reasonably accurate results after extracting wet antenna effects.
DATA RATE ANALYSIS AND COMPARING THE EFFECT OF FOG AND SNOW FOR FREE SPACE OP...IJEEE
In this paper the combined effect of specific attenuation due to Fog and Snow on FSO and RF links is considered. Optical wave attenuation due to low atmospheric visibility conditions causes a performance degradation of free space optical (FSO) communication systems.
1) Satellites provide a new tool for monitoring extreme rainfall events globally, including over oceans where gauges are sparse.
2) Analysis of TRMM satellite data shows that the relationship between maximum rainfall and duration (the Jennings law) exhibits two slopes for short and long durations, unlike the single slope seen in gauge data.
3) Satellites allow identifying regions experiencing the most extreme rainfall over timescales from days to years, such as Vietnam, Northeast India, and Colombia's Pacific coast.
Rain attenuation statistics for mobile satellite communications estimated fro...TELKOMNIKA JOURNAL
Mobile satellite communications will play a significant role in the next 5th generation mobile
services. The use of high-frequency bands will be the enabler of this advancement. However, at high
frequencies, excess rain attenuation causes severe signal losses and presents a major threat for the
system availability, especially in the tropical region. To that end, this study presents the rain attenuation
impact on mobile satellite communications estimated using long-term radar measurements in Malaysia, by
exploiting the horizontal structure of rain from the radar database and simulating inner-city and highway
mobile terminals scenarios. Additionally, a scaling factor was presented to scale available fixed satellite
terminals measurements to mobile terminals operating at the same locality under similar conditions. In
comparison to the available link measurements, the radar database was reliable enough to provide highly
accurate estimates. In all simulation scenarios, the mobile terminal will depart the rainy area soon enough
and experience lower attenuation statistics in comparison with the fixed terminal. The provided results will
help determine the overall future system performance, especially in tropical regions.
Estimation of Rain Attenuation based on ITU-R Model in Guntur (A.P), IndiaIDES Editor
Satellite communication systems operating at Ku
(12/14 GHz) and Ka band (20/30 GHz) frequencies are used
for broadband multimedia and internet based services. At these
frequencies, the signal will be affected by various propagation
impairments such as rain attenuation, cloud attenuation,
tropospheric scintillation, ionospheric scintillation, water
vapour attenuation, and rain and ice depolarization. Among
all the propagation impairments, rain attenuation is the most
important and critical parameter. In this paper, rain
attenuation is calculated at KL University, Guntur using
ITU-R rain attenuation model. The preliminary results of the
work will be used to calculate the attenuation experimentally
and comparison can be made, which helps to develop a new
rain attenuation model at Ku and Ka bands.
Estimating losses at 40-GHz downlink using non-meteorological techniques in h...TELKOMNIKA JOURNAL
The advancement of satellite communication has arisen tremendously where higher capacity communications systems are needed. Most satellite engineers are shifting to Ka, Q, and V-band upcoming since the low frequencies such as below 10 GHz are already congested. Actual measurement data at millimetre-wave frequencies in tropical regions are minimal. The prediction of rain attenuation at frequencies above 10 GHz is required to determine a reliable fade margin. In this paper, a statistical frequency scaling technique has been developed as an alternative way of estimating rain attenuation. The technique was derived based on the correlation between the attenuation ratio of a higher and lower frequency against the attenuation at a lower frequency. The attenuations from the proposed model were compared to the proposed frequency scaling by International Telecommunication Union-R (ITU-R) as well as the conventional ITU-R rain prediction model. To deliver a reliable model, validation methods have been done using a set of data with different years and locations in tropical regions. A dependent prediction technique with the lowest root mean square error (RMSE) value and error was produced. This technique is beneficial in applying suitable mitigation techniques to moderate rain fade in tropical regions.
Towards the identification of the primary particle nature by the radiodetecti...Ahmed Ammar Rebai PhD
This document summarizes a study using the CODALEMA experiment to analyze radio signals from air showers and identify properties of primary cosmic ray particles. It describes:
1) Analyzing time delays of radio signals compared to a plane wavefront hypothesis and finding systematic deviations, indicating the wavefront is curved.
2) Developing a model to reconstruct the emission center position based on fitting time delays to a parabolic function dependent on curvature radius and antenna distances.
3) Applying the model to 450 selected CODALEMA events and comparing reconstructed shower core positions to results from other models, finding consistency.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Wdm based fso link optimizing for 180 km using bessel filtereSAT Journals
Abstract Free space optical link is a growing field in communication due to its advantage of wide bandwidth, high security and easy installation. A wavelength division multiplexing (WDM) access network using free space optical (FSO) communication in different weather conditions like haze and rain are discussed in this article and find out the possibility of communication link up to 180 km in clear weather with 2.5 Gbps data rate on the wavelength of 1550 nm and up to 54 km in haze condition using same data rate & wave length. Further the effect of using two different low pass filter (Gaussian and Bessel) at the receiver are discussed and conclude that Bessel filter is better on 2.5 Gbps data rate for WDM based FSO link. Keywords: optical communications, wavelength Division Multiplexing (WDM), free space optics (FSO)
International Journal of Business and Management Invention (IJBMI) is an international journal intended for professionals and researchers in all fields of Business and Management. IJBMI publishes research articles and reviews within the whole field Business and Management, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Investigation of time diversity gain for earth to satellite link using rain r...journalBEEI
The utilization of satellites for communication systems has expanded considerably in recent years. C and Ku-bands of frequencies are already congested because of high demand. Future directions of satellite communications are moving towards Ka and V-bands. Earth to satellite communications are moving towards higher frequency bands in future which are more sensitive to environment. Rain causes severe degradation in performances at higher frequency bands specially in tropical regions. Several mitigation techniques are proposed to design reliable system. Time diversity is one of the potential candidate for it. However, time diversity analysis requires measured rain attenuation data. For future high frequency link design those data are not available at most of the places. This thesis proposes a method to utilize 1-minute rain rate to analyze time diversity technique at any desired frequency. This paper proposes a method to utilize 1-minute rain rate to analyse time diversity rain rate gain. In proposed method, it is assumed that rain rate gain with delay can represent rain attenuation gain with delay for same period of time at same location. The characteristics of rain rate and rain attenuation almost same because the attenuation causes due to rain. One year measured rain rate in Malaysia is used to predict rain rate gain. The measured gain at 12.225 GHz signal is compared with that predicted by ITU-R based on rain rate measurement and is found good agreement. Hence it is recommended that the time diversity gain can be predicted using measured rain rate for any desired frequencies.
Determination of Propagation Path Loss and Contour Map for FUTA FM Radio Fede...IOSR Journals
Abstract: FM signal propagation through the troposphere interacts with the terrain as obstacles and reflection planes. To understand the degree of interaction, signal strength measurements of the 93.1MHz frequency modulated Radio located at Federal University of Technology; Akure, Nigeria was carried out in the area surrounding the station. The paper reviews the various models for predicting transmission loss and employed the long rice irregular terrain model for its versatility for the study. The losses along the paths were determined and this was compared with the path loss predicted by the irregular terrain model and this was highly correlated. The result offers useful data for developing the contour map of the propagation loss which was developed for the station. It was concluded that with the irregular terrain model predictions can be used for accurate spectrum management in Nigeria. Keywords: Signal Strength, Transmission Loss, Terrain, Spectrum Management.
Determination of Propagation Path Loss and Contour Map for FUTA FM Radio Fede...IOSR Journals
FM signal propagation through the troposphere interacts with the terrain as obstacles and reflection
planes. To understand the degree of interaction, signal strength measurements of the 93.1MHz frequency
modulated Radio located at Federal University of Technology; Akure, Nigeria was carried out in the area
surrounding the station. The paper reviews the various models for predicting transmission loss and employed
the long rice irregular terrain model for its versatility for the study. The losses along the paths were determined
and this was compared with the path loss predicted by the irregular terrain model and this was highly
correlated. The result offers useful data for developing the contour map of the propagation loss which was
developed for the station. It was concluded that with the irregular terrain model predictions can be used for
accurate spectrum management in Nigeria
Use of mesoscale modeling to increase the reliability of wind resource assess...Jean-Claude Meteodyn
During wind farm design phase, the wind direction distribution is a crucial information for wind turbine layout optimization. However, in complex terrains, the wind rose at hub height of the wind turbines can be quite different from met mast measurement.The study shows that in complex terrains, the use of mesoscale modeling provides a complement to met mast measurement. It allows to better determine the turbine-specific wind rose and to reduce the uncertainty in wind resource assessment. The coupling of mesoscale and CFD model allows to produce high resolution wind map, by taking into account both mesoscale and microscale terrain effects.
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This document summarizes a study on the importance of exercise in maintaining physical and mental fitness for school children. It discusses how physical and mental fitness are developed through participation in regular physical exercises and cannot be achieved solely through classroom learning. The document outlines different types and components of fitness and argues that developing fitness should be a key objective of education systems. It recommends that schools ensure pupils engage in graded physical activities and exercises to support their overall development.
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This document discusses evaluating the link budget for effective 900MHz GSM communication. It describes the basic parameters needed for a high-level link budget calculation, including transmitter power, antenna gains, path loss, and propagation models. Common propagation models for 900MHz that are described include Okumura model for urban areas and Hata model for urban, suburban, and open areas. Rain attenuation is also incorporated using the updated ITU model to improve communication during rainfall.
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A synthesis of taylor’s and fayol’s management approaches for managing market...Alexander Decker
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A survey paper on sequence pattern mining with incrementalAlexander Decker
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This document surveys trust architectures that leverage provenance in wireless sensor networks. It begins with background on provenance, which refers to the documented history or derivation of data. Provenance can be used to assess trust by providing metadata about how data was processed. The document then discusses challenges for using provenance to establish trust in wireless sensor networks, which have constraints on energy and computation. Finally, it provides background on trust, which is the subjective probability that a node will behave dependably. Trust architectures need to be lightweight to account for the constraints of wireless sensor networks.
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TrustArc Webinar - 2024 Global Privacy SurveyTrustArc
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Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind für viele in der HCL-Community seit letztem Jahr ein heißes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und Lizenzgebühren zu kämpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklären Ihnen, wie Sie häufige Konfigurationsprobleme lösen können, die dazu führen können, dass mehr Benutzer gezählt werden als nötig, und wie Sie überflüssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige Ansätze, die zu unnötigen Ausgaben führen können, z. B. wenn ein Personendokument anstelle eines Mail-Ins für geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche Fälle und deren Lösungen. Und natürlich erklären wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt näherbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Überblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
Diese Themen werden behandelt
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Monitoring and Managing Anomaly Detection on OpenShift.pdfTosin Akinosho
Monitoring and Managing Anomaly Detection on OpenShift
Overview
Dive into the world of anomaly detection on edge devices with our comprehensive hands-on tutorial. This SlideShare presentation will guide you through the entire process, from data collection and model training to edge deployment and real-time monitoring. Perfect for those looking to implement robust anomaly detection systems on resource-constrained IoT/edge devices.
Key Topics Covered
1. Introduction to Anomaly Detection
- Understand the fundamentals of anomaly detection and its importance in identifying unusual behavior or failures in systems.
2. Understanding Edge (IoT)
- Learn about edge computing and IoT, and how they enable real-time data processing and decision-making at the source.
3. What is ArgoCD?
- Discover ArgoCD, a declarative, GitOps continuous delivery tool for Kubernetes, and its role in deploying applications on edge devices.
4. Deployment Using ArgoCD for Edge Devices
- Step-by-step guide on deploying anomaly detection models on edge devices using ArgoCD.
5. Introduction to Apache Kafka and S3
- Explore Apache Kafka for real-time data streaming and Amazon S3 for scalable storage solutions.
6. Viewing Kafka Messages in the Data Lake
- Learn how to view and analyze Kafka messages stored in a data lake for better insights.
7. What is Prometheus?
- Get to know Prometheus, an open-source monitoring and alerting toolkit, and its application in monitoring edge devices.
8. Monitoring Application Metrics with Prometheus
- Detailed instructions on setting up Prometheus to monitor the performance and health of your anomaly detection system.
9. What is Camel K?
- Introduction to Camel K, a lightweight integration framework built on Apache Camel, designed for Kubernetes.
10. Configuring Camel K Integrations for Data Pipelines
- Learn how to configure Camel K for seamless data pipeline integrations in your anomaly detection workflow.
11. What is a Jupyter Notebook?
- Overview of Jupyter Notebooks, an open-source web application for creating and sharing documents with live code, equations, visualizations, and narrative text.
12. Jupyter Notebooks with Code Examples
- Hands-on examples and code snippets in Jupyter Notebooks to help you implement and test anomaly detection models.
Programming Foundation Models with DSPy - Meetup SlidesZilliz
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Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slackshyamraj55
Discover the seamless integration of RPA (Robotic Process Automation), COMPOSER, and APM with AWS IDP enhanced with Slack notifications. Explore how these technologies converge to streamline workflows, optimize performance, and ensure secure access, all while leveraging the power of AWS IDP and real-time communication via Slack notifications.
Threats to mobile devices are more prevalent and increasing in scope and complexity. Users of mobile devices desire to take full advantage of the features
available on those devices, but many of the features provide convenience and capability but sacrifice security. This best practices guide outlines steps the users can take to better protect personal devices and information.
Fueling AI with Great Data with Airbyte WebinarZilliz
This talk will focus on how to collect data from a variety of sources, leveraging this data for RAG and other GenAI use cases, and finally charting your course to productionalization.
A high performance model for rainfall effect on radio signals
1. Journal of Information Engineering and Applications www.iiste.org
ISSN 2224-5782 (print) ISSN 2225-0506 (online)
Vol.3, No.7, 2013
25
A High Performance Model for Rainfall Effect on Radio Signals
Jonathan U. Agber Johnson Mise Akura
Department of Electrical and Electronics Engineering
Federal University of Agriculture, Makurdi, Benue State, Nigeria.
*E-mail: juagber@gmail.com Email: akuramise@yahoo.com
Abstract
A mathematical model for calculating the attenuation due to rain is derived using spheroid rain drops over a
broad frequency range. The model is based on the limitation of Okumura’s model which does not account for
other forms of losses, like rainfall, haze, etc. Numerical results are obtained from the simulation of the free space
model and the formulated model with drop size of 3.5mm over a broad frequency range of 3GHz, 5GHz and 10
GHz using MATLAB software package. The validity of the formula for computing rain attenuation is then
checked by comparing the results of the simulation of the path loss and received power as function of distance
between the separations of two antennas with that of the free space model. The results obtained show that the
attenuation (path loss) due to rainfall is 75.46% greater than that due to free space; and the received power for
the rainfall model is 24.61% less than that due to the free space model.
Keywords: Radio communication, Radio wave interference, Rainfall model, Rainfall losses, Rainfall attenuation
1. Introduction
The medium through which radio waves traverse places some basic limitations on the performance of wireless
telecommunication systems. This has a very big role to play in wireless communication systems; it is the main
contributor to many impairments of wireless systems performance. The huge impairments make wireless
communication unpredictable and offer random analysis. Rain attenuation is caused by the scattering and
absorption of electromagnetic waves by drops of liquid water. The scattering diffuses the signal, while
absorption involves the resonance of the waves with individual molecules of water. Absorption increases the
molecular energy corresponding to a slight increase in temperature, and results in an equivalent loss of signal
energy. The study of radio waves scattering and absorption by raindrops therefore becomes very important since
rain attenuation data due to radio waves scattering and absorption are needed in many important applications,
including microwave propagation systems, remote sensing systems, radar systems, and radio link systems [1].
From the view point of radio communication network engineering, communication medium can be viewed as
imperfect bit pipes; the imperfection being that the bit pipes can delay, loose or modify the information they
carry [2]. Rain attenuation is affected by factors such as rain rate, operating frequency, the physical size of drops
and polarization [1], [3]. During a period of heavy rainfall, raindrops fall with a significant canting angle because
of the strong winds usually associated with such events. Hence, rain attenuation is related to the rain rate and the
scattering and absorption mechanism of raindrops at the operating frequency [4]. Although studies of rain
attenuation of microwave signals have been conducted in Europe and the United States dating back to the 1940s,
it is now common knowledge that the rain-attenuation models and raindrop size distribution models are highly
regionalized[5], [6]. So many people have worked on rain rates and rain attenuation models: Calla et.al [7]
worked on the effect of rain and dust on propagation of radio waves within millimeter wavelength. In their
experiment, they placed rain gauge, and dust particle near the receiver to avoid shadowing effect due to nearby
objects. The specification of the LOS link can also be used for the horizontal path attenuation. The vertical path
attenuation was then estimated by subtracting clear sky attenuation (free space) from excess attenuation (rainy
medium) due to rain. Henry researched on rain induced bistatic scattering at 60 GHz. In their work, they
operated at 94 GHz as proposed by Gloaguen and Lavergnat. The first order multiple scattering approximation is
applicable to the scattering at 60 GHz. Hence they used the bistatic radar equation [8] for the particle scattering
by rain. Ojo et.al. [9] worked on rain rate and rain attenuation prediction for satellite communication in Ku and
Ka bands over Nigeria. They used a model that was developed by Moupfouma and Martins to predict rain rate
and concluded that the model is good for tropical and temperate climate [10]. The map for the rain attenuation
over Nigeria was developed using the ITU rain attenuation [11]. The results obtained from their research confirm
that 0.1% of time of rain attenuation is needed for very small aperture terminal (VSAT) network service
availability. Capsoni et.al. [12] researched on the multiple excel model for the prediction of the radio
interference due to hydrometeor scattering. They used a physically-based method for the prediction of the radio
interference due to hydrometeor scattering. The coupling-by-scattering mechanism relies on the bistatic radar
equation which allows for evaluation of interference levels when the electrical and geometrical characteristics as
well as the distribution of scatterers in the common volume are known. Hence, they used the bistatic radar
equation (BRE) to solve for a population of isolated exponential rain cells (EXCELL) model which generates
complex synthetic rain fields reflecting the total first and second order features of the rainfall process. Saikia et
2. Journal of Information Engineering and Applications www.iiste.org
ISSN 2224-5782 (print) ISSN 2225-0506 (online)
Vol.3, No.7, 2013
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al [13] worked on rain attenuation of centimeter radio waves in which they used the laser disnometer for
calibrating and profiling of rain drop size distribution. The rain drop signature is extracted by allowing the drops
to pass through a controlled field of view of a sensor. The laser beam was used as the signal source, the
phototransistor was used as detector-cum-amplifier and optical fibres as trans-receiving ports. Rain drops size
and rain rate at different weather condition were measured. The specific attenuation of the line of sight radio
signals at 10-30 GHz of various drop diameters were then calculated using standard attenuation equations and
model values of scattering function.
2. Development of the model
Radio signals are transmitted from Tx, and when they encounter drops of rain, the waves are scattered in diverse
directions and others are absorbed by the rain drops; which acts as poor dielectric, absorbing power from the
radio waves and dissipating the power by heat loss. This is shown in Figure 1.
In deriving an expression for the attenuation of electromagnetic waves traversing through rain, consideration is
given to a volume, which is bounded by a cone of the power flux lines and two spherical surfaces as shown in
Figure 2. iP corresponds to the component of power emitted from the transmitter, Tx, which is the source power.
Part of the power is absorbed in the volume while the other part is scattered by the different components in the
volume. Those components of the power that are neither scattered nor absorbed in the volume are refracted and
they reach the receiver, Rx [14].
If s cP represents the power that is scattered by the component of rain drops in the volume, while a bP
represents the component of power that is absorbed by rain drops in the volume, and rP represents the
component of power that is refracted (transmitted signals that reach the receiver), then, the power balance in the
beam is given by [15] as:
(1 )i s c a b rP P P P= + +
This equation is feasible because, the incident power iP radiated from the source power is split into various
components of power as the waves come in contact with a drop of rain [14]. Each of the power components can
Tx
Scattered waves
Figure 1: Interference of Signals by Rain Drop
Wave front Rain drop
Rx
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27
therefore be expressed in terms of the time-average Poynting vector which is given by [16] as:
*1
( ) { ( , t ) } { E ( , t ) H ( , t ) } ( 2 )
2
a v eW W Rα α α α= = ×
where: ( ,t)W α is the power density as function of distance and time,
E( ,t)α is the electric field,
*
H ( ,t)α is the magnetic field strength,
α is the distance between the two antennas.
The equation of the time-average Poynting vector gives the value of the power density( )2
/w m . Hence each
component of the power can be easily evaluated in terms of the time-average value of the Poynting vector, such
that
2
( ) n ( 3 )i a vP W dα α= Ω
where n is the normal of the first surface,
dΩ is the differential solid angle which is defined as sind dθ φΩ = ,
2
dα Ω is the spherical surface area,
θ is the elevation or altitude,
φ is the azimuth – angular measurement in a spherical coordinate system.
As the symmetry is spherical, the projection of the average power density is the same as the average power
density [13]. Thus,
( ) W n ( 4 )a v a vW α =
Each component of power can, therefore, be expressed in terms of the time-average Poynting vector [17]. To
obtain the various components of power discussed earlier on, consideration is given to the drop size distribution
denoted as ( )N d , the scattering cross section and absorption cross section in the volume in which the signal is
scattered or absorbed. The scattering cross section is the region within which the signal is scattered in the volume
and is denoted as scσ , while the region or area within which the signal is absorbed by the rain drop in the
volume is denoted as abσ . Hence the total cross section of scattering and absorption of the signal in the volume
is the sum of the scattering cross section and absorbing cross section and is given by [14] as:
( 5 )t o t a l s c a bσ σ σ= +
This leads to the assumption that the total power loss is due to scattering and absorption [14]. The power loss
due to scattering can be obtained by multiplying the average power density, ( )W α , the volume in which the
signal is scattered, V , the drop size distribution, ( )N d , and the scattering cross section scσ [14]. Hence
iP
α
Figure 2: Section of a Cone Bounded by Power Flux
lines
scP
( ) P ( )abd W dα α α α+ +Tx
4. Journal of Information Engineering and Applications www.iiste.org
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Vol.3, No.7, 2013
28
( ) ( )
, ( 6 )
( ) ( )
s c s c
a b a b
P W a V N d
S i m i l a r l y
P W a V N d
σ
σ
=
=
The volume V can therefore be approximated by
2
d dα α Ω; that is multiplying the surface area by the solid
angle [17], then
2
2
( ) ( )
( 7 )
( ) ( )
s c s c
a b a b
P W a d d N d
a n d
P W a d d N d
α α σ
α α σ
= Ω
= Ω
The refracted power is given in equation (8) as:
2
( )( )( ) (8)rP W d dα α α α α= + + Ω
Hence equation (1) becomes:
2 2 2
2
( ) ( ) ( ) ( ) ( )
( )( )( )
sc a bd W d W d d N d W d d N d
W d d
α α α α α σ α α α σ
α α α α α
Ω = Ω + Ω
+ + + Ω
which is then simplified to yield equation (9)
2 2
2( )( )( ) ( )
( ) ( ) 0 (9)total
W d d W
W N d
d
α α α α α α α
α α σ
α
+ + +
+ =
Hence,
2
( )dα α+ from equation (9) can be further simplified by applying Taylor’s series expansion, in which
the equation will reduce to:
2
2 2 2 2
( ) 1 1 2 , 1
d d d
d d for
α α α
α α α α α α
α α α
+ = + = + = + <<
Hence
2 2
2( )( )( )
2 ( )( d ) ( ) 0, 0total
W d d W
W WN d d
d
α α α α α α
α α α α σ α
α
+ + +
+ + + = →
As 0dα → , the differential equation for the transmitted power density becomes:
3 2( )
( ) ( ) 2 ( ) 0 (10)total
dW
N d W W
d
α
α α α σ α α
α
+ + =
Equation (10) has the general solution of second-order differential equation
[ ( ) ]
2
( ) , 0 (11)
totalN d
c e
W
σ α
α α
α
−
= ≠
where c is an arbitrary constant which can be evaluated by considering the power density, ( )isoW a emitted in a
spherical wave beam generated by an isotropic antenna with a time-average radiated power, Ps, (source power)
[17]. The equation of the emitted power density in a spherical wave beam generated by an isotropic antenna is
given in equation (12), as:
2
( ) (12)
4
s
iso
P
W α
πα
=
If equation (11) is compared with equation (12), which is the case for signals propagating in free space, i.e.,
( ) 0totalN d σ α = then the constant c can be found as follows:
2 2
( ) ( ) , 0
4
s
iso av
P c
W W aα α
πα α
= = = ≠
which gives
4
sP
c
π
=
and thus reducing equation (11) to
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29
[ ( ) ]
2
( ) , 0 (13)
4
totalN d
sP e
W a
σ α
α
πα
−
= ≠
However, an isotropic antenna is not realizable in practice and is useful only for comparison purposes. A more
practical type is the directional antenna which radiates more power in some directions and less in other directions
[15]. The commonly used parameter to measure the overall ability of an antenna to direct radiated power in a
given direction is a dimensionless quantity called the directive gain. The directive gain is defined in terms of the
radiation intensity, ( , )I θ φ , which is the time-average power per unit solid angle. Since there are
2
α square
meters for each unit solid angle, radiation intensity ( , )I θ φ equals
2
α multiplied by the magnitude of the time-
average Poynting vector, avW [18].
Therefore,
2
( , ) ( , , ) (14)avI Wθ φ α α θ φ=
The total radiated time–average power is related with the radiation intensity given by Lin and Chen [18] as:
∫ Ω= )15(),( dIPs φθ
Since the antenna has the ability to direct radiated power in a given direction, the directive gain of the antenna
also has a major role to play in the quality and quantity of the signals obtained by the receiver. The directive gain
( , )dG θ φ of an antenna pattern is the ratio of the radiation intensity I( , )θ φ in the direction to the time-
average radiated power [18]:
( , )
G ( , ) (16)
/ 4
d
s
I
P
θ φ
θ φ
π
=
Since the radiation from the antenna is not uniformly distributed, the expression of the attenuated time–average
power density equation (13) has to be improved to include this property. Substituting equation (14) into equation
(16) yields
[ ( ) ]
2
( ) ( , ), 0 (17)
4
totalN d
s
av d
P e
W a G
σ α
θ φ α
π α
−
= ≠
If a receiving antenna is used to measure the transmitted power at a distance from the transmitter, that is the
power that is neither absorbed nor scattered in the volume, the properties of the receiving antenna have to be
considered [19]. The incident waves are being received in an area that is small compared to the physical area of
the receiving antenna. This is the effective area, A ( , )e θ φ of the antenna and is defined as the ratio of the
average power PL delivered to a matched load to the time–average power density of the incident wave [19].
Hence,
P W A ( , )L e θ φ=
PL is the maximum average power transferred to the load when the receiving antenna is oriented with the
polarization of the incident wave [19]. The ratio of the directive gain and effective area of an antenna is a
universal constant [19] and;
2
4
( , ) ( , ) ( , ) (18)d r eG G Aθ φ θ φ θ φ
λ
= =
where λ is the wavelength of the radio signal.
An expression for the received power RP can therefore be obtained by multiplying the receiving antenna
effective area ( , )eA θ φ with the expression for the transmitted time-average power density ( , )tG θ φ [17].
[ ( ) ]
2
( , ) A ( , ) (19)
4
totalN d
s
R t e
P e
P G
σ α
θ φ θ φ
πα
−
=
Substituting equation (18) into equation (19) for ( , )eA θ φ gives
2
[ ( ) ]
2
G e (20)
4
totalN ds
R t r
P
P G σ αλ
πα
−
=
where Gr is the receiver gain.
6. Journal of Information Engineering and Applications www.iiste.org
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Table 1: The simulated results of the path loss for the rainfall attenuation model (RAM) and free space model
Separation between
two antennas (Km)
Data due to the effect of rainfall Data due to the effect of free space
3Ghz 4GHz 10GHz 3Ghz 4GHz 10GHz
1 469 475 493 97.1 103 121
2 483 489 507 111 117 135
3 491 497 515 119 125 143
4 497 502 521 125 131 149
5 501 507 525 129 135 153
6 505 511 529 133 139 157
7 508 514 532 136 142 160
8 511 516 535 139 144 163
9 513 519 537 141 147 165
10 515 521 539 143 149 167
11 517 523 541 145 151 169
12 519 524 543 147 153 171
13 520 526 544 148 154 172
14 522 527 546 150 156 174
15 523 529 547 151 157 175
16 524 530 548 153 158 177
17 526 531 550 154 159 178
18 527 532 551 155 161 179
19 528 534 552 156 162 180
20 529 535 553 157 163 181
21 530 536 554 158 164 182
22 531 537 555 1.59 165 183
23 532 537 556 160 166 184
24 532 538 557 161 166 185
25 533 539 557 161 167 186
26 534 540 558 162 168 186
27 535 541 559 163 169 187
28 536 541 560 164 169 188
29 536 542 560 164 170 188
30 537 543 561 165 171 189
Two antennas can be aligned in such a way that they have maximum value of the directive gain for effective
radio communication. Hence, the maximum directive gain of an antenna can be represented by the directivity of
the antenna [14]. Thus, if the directivity of the transmit antenna is represented by tD and that of the receive
antenna represented by rD , equation (19) can be restated as:
2
[ ( ) ]
2
e (21)
4
totalN dt rR
s
D DP
P
σ αλ
π α
−
=
The path loss denoted as L can be evaluated by finding the reciprocal of equation (20), given as;
2
[ ( ) ]
2
4
10 log e (22)totalN ds
R t r
P
L
P D D
σ απα
λ
= =
7. Journal of Information Engineering and Applications www.iiste.org
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Table 2: The simulated results of the received power for the rainfall attenuation model (RAM) and free space
model
Separation between
two antennas (Km)
Data due to the effect of rainfall Data due to the effect of free space
3Ghz 4GHz 10GHz 3Ghz 4GHz 10GHz
1 213 211 203 1030 973 825
2 207 205 197 901 857 741
3 204 201 194 840 801 699
4 201 199 192 801 766 672
5 200 197 190 774 741 652
6 198 196 189 752 721 637
7 197 195 188 735 705 625
8 196 194 187 721 692 614
9 195 193 186 709 681 606
10 194 192 186 699 672 598
11 193 191 185 690 663 591
12 193 191 184 681 656 585
13 192 190 184 674 649 580
14 192 190 183 667 643 575
15 192 189 183 661 637 570
16 191 189 182 656 632 566
17 190 188 182 650 627 562
18 190 188 182 646 623 559
19 189 187 181 641 618 555
20 189 187 181 637 614 552
21 189 187 181 633 611 549
22 188 186 180 629 607 547
23 188 186 180 626 604 544
24 188 186 180 623 601 541
25 188 186 179 619 598 539
26 187 185 179 616 595 537
27 187 185 179 614 593 535
28 187 185 179 611 590 532
29 186 184 178 608 588 531
30 186 184 178 606 585 529
3. Validation of the model
The formula for the rain attenuation developed using incident electromagnetic waves for oblate spheroidal
raindrops with mean (effective) drop radius ranging up to 0.35 cm and frequencies of 3GHz to 10 GHz; is
compared with free space model of the Okumura- Hata free space model.
The formulated rainfall model and the free space model are simulated using MATLAB software package and
data obtained from the simulation and the results are tabulated in Tables 1 and 2. From the simulation, the
received power and the path loss in both cases are plotted against the distance between the separation of the
transmit and receive antennas and the result is compared and summarized as shown in Figures 3, 4, 5 and 6.
Table 2: The simulated results of the received power for the rainfall attenuation model (RAM) and free space
model
4. Analysis of results
4.1 Path loss as a function of distance for the rain attenuation and free space models for signals of 3, 4,
and 10 GHz
Path loss is an important parameter which must be taken into consideration when planning for a radio
communication system [19]; this helps to determine the distance at which one antenna will be sited from the
other. The parameter is also important in determining the hand off speed and cell sizes [20]. The simulation
results, shown graphically in Figures 3 and 4, are for path loss plotted against the distance between the
separations of the two antennas for the rain attenuation model and free space model. From the graphs, the output
result of the rain attenuation model is higher compared to the output result of the free space propagation model
for all the three frequencies. This accounts for the fact that, degradation of the radio signals occurs as the waves
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traverse through rain. It is also easy to see that the two curves rise exponentially as the separation between the
antenna increases; this could be as a result of the fact that the attenuation produced increases exponentially as the
signal decays gradually.
Though, there is exponential rise in the two curves in the same manner, there is a relatively higher path loss in
the rain attenuation model than the free space model, thus confirming the result obtained by Head, [21].The
analysis of the behavior of the graph at 10GHz is not different from that at 3GHz and 4GHz. From the graph, the
level of attenuation of the radio signal at 10GHz is higher compared to the other operating frequencies [22, 23].
Thus, one can conclude that as the operating frequencies increase, there is higher level of attenuation of the
signals. Also, an increase in the separation between the two antennas results in higher path loss.
Figure 3: The Graph of the Rain Attenuation Path Loss Model Against the Separation Between the Two Antenna
Figure 4: The Graph of the Free Space Path Loss Against the Separation Between the Two Antenna
4.2 Received power as a function of distance for the rain attenuation and free space models for signals of
3, 4, and 10 GHz
The received power is a parameter that is very significant in communication; this parameter was also obtained
during simulation and plotted in Figures 5 and 6. The signal strength at the receive antenna determines the
amount of power that is satisfactorily required to obtain coverage in an area. It was observed from Figures 4 and
5 that the output results at various frequencies for both models slope down gradually; with the graphs
representing the output results for the free space higher than that due to the effect of rain.
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Figure 5: The Graph of the Received Power Against the Separation Between the Two Antennas for the Rainfall
Model
Figure 6: The Graph of the Received Power Against the Separation Between the Two Antennas for the Free
Space Propagation Model (FSPM)
The behavior of the graphs is because, as the attenuation (path loss) increases with increase in distance, the
received power decreases as the distance between the receive and transmit antennas increases. A similar
observation was made by Gilbert, [24]. It was also observed that the received power is higher in the free space
since the signal at all frequencies traverses under a clear line of sight, while that due to the effect of rain is
absorbed by drops of rain or scattered in diverse directions therefore, has higher attenuation and less received
power [20]
5. Conclusions
The equation for the path loss, equation (22), derived here is useful for the calculation of specific microwave
attenuation due to raindrops in the frequency range from 0.6 to 100 GHz. It provides a simple method for quickly
calculating the microwave rain attenuation as a function of frequency, the separation between two antennas and
mean radii of raindrops. This formula thus provides a simple and inexpensive method for calculating attenuation
caused by raindrops as they are propagated, which otherwise requires complicated, tedious, and expensive
algorithms. By inputting the parameters, as used in the formula, a new numerical method for the calculation of
specific rain attenuation is established. The validity of the formula for calculating the specific rain attenuation is
then checked by comparing the obtained results of specific rain attenuation with those obtained by free space
model.
The calculation of microwave rain attenuation can now be carried out for a wide range of frequencies and rain
rates. This formula of specific rain attenuation makes it practical for direct use by wireless communication
system designers. From the studies, it was observed that when the specific rain attenuation is predicted in
different areas, it is important to take into account the effects of drop-size and the operating frequencies.
10. Journal of Information Engineering and Applications www.iiste.org
ISSN 2224-5782 (print) ISSN 2225-0506 (online)
Vol.3, No.7, 2013
34
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11. Journal of Information Engineering and Applications www.iiste.org
ISSN 2224-5782 (print) ISSN 2225-0506 (online)
Vol.3, No.7, 2013
35
Jonathan U. Agber received MSc degree in electromechanical Engineering from
the Moscow Power Engineering Institute, Moscow, Russia in 1976, PhD degree in
Electrical Engineering from the University of Newcastle Upon Tyne in the UK in
1985. He is a Senior Lecturer in the Department of Electrical and Electronics
Engineering, The Federal University of Agriculture, Makurdi, Benue State,
Nigeria. He is a registered engineer and Member Nigerian Society of Engineers.
His research interest includes CAD, simulation and control of incremental motion
devices and software development.
Johnson M. Akura is a lecturer with the Department of Electrical and Electronics
Engineering, The Federal University of Agriculture, Makurdi, Benue State, Nigeria
where he obtained B.Eng degree in 2006. He received his M.Eng at the University
of Nigeria Nsukka in 2012. His research interest includes semiconductor devices
and nano-technology.
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