Tropospheric Effect 4. Project Description : Abstract( rain attenuation) this is the report for the rain attenuation is "estimation of microwave power margin losses due to earth's atmosphere and weather in the frequency range of 3-30 ghz ". Heavy precipitation severely degrades the performance of satellite communication systems operating at frequencies higher than 10 GHz. It is a measured parameter, which is a function of many factors . Rain Attenuation Model of Satellite 3. As an example, for Ottawa, the rain attenuation exceeds 1.9 dB for 0.1 percent of the time. The simplest way to compensate the rain fade effect in satellite communications is to increase the transmission power: this dynamic fade countermeasure is called uplink power control (UPC). Rain induced attenuation prediction is considered a fundamental step in the analysis of satellite communication links for frequencies above 10 GHz, due to their major effect on the satellite communication link and services. Several adaptive compensation techniques have been elaborated to counteract its effects and most often applied one at a time. In the design and planning of reliable communication systems, rain attenuation prediction studies become necessary [5]. Downlink rain-fade margin - In EU, there is performed the study of the satellite rain attenuation prediction and it's compensation schemes of the satellite link using OTS, OLYMPUS, etc with COS 255 and 280 cooperative projects Using this technique, the modulation of a link between a satellite and antenna can be automatically lowered to compensate for interference caused by atmospheric interference. The present paper proposes the contemporary exploitation of different techniques in a combined approach. Some problems dea- ling with the study of the performance of microwave systems working at these frequencies are treated here. Rain attenuation may affect your signals even if the storm is many miles removed from the receiving antenna, due to the line of sight, or elevation angle, between the transmitting and receiving station. This paper proposes a model for predicting rain attenuation in the tropical region. For the implementation of effective countermeasures, rain attenuation statistics are needed, second order statistics in particular. Rain attenuation predictions. Rain attenuation is studied for 19.8 and 20.73 GHz respectively. 2 Satellite G/T EIRP (Equivalent Isotropic Radiated Power) SFD (Saturated Flux Density) Amplifier Characteristic Downlink Path Loss Rain Attenuation Receiving Earth Station Antenna Gain LNA /LNB Noise Temperature Other Equipment Signal Power Calculation Antenna Gain G = (* d / )2 [dBi] Where, = C / f , C = Speed of light f = frequency of interest Rain attenuation - The attenuation of the signal due rain is the . However, GEO satellite communication suffers from large delay (i.e., 270 ms), is not able to benefit from frequency reuse, and the needed power to transmit to GEO is extremely high. Abstract The important factor to be considered in the link budget estimation for satellite communication systems, operating at frequencies above 10 GHz is the rain attenuation. Rain attenuation values of hourly rain fall rates in the month of August 2010 RANK RAIN RATE (mm/h) FREQUENCY (GHz) RAIN ATTENUATION (dB) Rain attenuation prediction model can be categorized into s empirical and -physical models. It is the first Africa geosynchronous communication satellite and is positioned at 42.50 E. Frequency Scaling of Rain Attenuation for Satellite Communication Links Jeff D. Laster and Warren L. Stutzman, Fellow, ZEEE Abstruct-One year of copolarized signal data from the OLYM- PUS satellite's 12, 20, and 30 GHz beacons were examined for frequency scaling of attenuation. In Akobra S. et al, other than rainfall, the effect of Hamartan, sunshine and cloudy weather are .

It is also commonly known as the military band. INTRODUCTION frequency and is highly correlated with rain rate. Rain attenuation is a major factor limiting the reliabi- lity of both terrestrial and earth-to-satellite paths opera- ting at frequencies above 10 GHz. AbstractThe X-band satellite communication (satcom) has been conventionally set aside for military and government organizations. semi mpirical model is An e 1. Final Reports on Rain Attenuation Studies for Communication Systems Operating in Tropical Regions. Frequency scaling of rain attenuation for satellite communication links. Rain rate and rain attenuation predictions are one of the vital steps to be considered when analyzing a microwave satellite communication links at the Ku and Ka bands. is an encouraging step towards a highly comprehensive and accurate prediction of tropospheric impairments in Ka-band satellite communications in the tropical region. Crane, R. K., "Prediction of the effects of rain on satellite communication system," Proceedings of the IEEE, Vol. Measurements of attenuation and depolarization, primarily due to rain, of the 12-GHz communication technology satellite (CTS) beacon have been made at Crawford Hill, Holmdel, NJ. Intense rain can cause large attenuation values on an Earth-space link. 9.06o N and longitude 7.48o E. Rain attenuation and link outages is a predominant challenges for satellite service for both direct to home (DTH) television or broadband internet service [2]. The higher frequency bands such as Ku (12/14 GHz) and Ka (20/30 GHz) are most effective in satellite communication and promise future demands of higher data rate services. Moreover, the attenuation is considered as blockage at extreme weather . Where T rain is known as apparent absorber temperature. Skip to Article Content; Skip to Article Information; Search within. The standard method of . Slant path rain attenuation measurements were carried out in Singapore by analyzing the beacon signals from two satellites, namely WINDS and GE23, operating at frequencies of 18.9 and 12.75 GHz, respectively. the frequency being used. The DAH Model for rain attenuation prediction is valid for Indonesia, as is the ITU model. Rain attenuation at Ka-band is a severe phenomenon that drastically impairs satellite communications at these frequencies. In Ka-band(30/20 GHz), however, the effect of rain attenuation is more significant than in lower frequency bands, such as Ku-band(14112 GHz) and C-band (6/4 GHz) 111. Rain effects become most se at wavelength . One of these problems, called rain fade, is associated with the transmission of electromagnetic signals through moisture in the Earth's atmosphere. Rain attenuation predictions have become one of the vital considerations while setting up a satellite communication link. This study investigates the effect of rain attenuation in the Space-to-Earth direction for a Nigerian Communication Satellite (NigComSat-1R) located at 42.5 degrees east longitude. Rain Attenuation Prediction Models The amount of fading due to rain is a function of the I. Search term . * Limited knowledge of the rain process makes it difficult to come up with accurate predictions of rain attenuation . One of the problems faced by the satellite communication is rain fade; responsible for distortion phenomenon in signals being propagated at KU band during rain and droplet precipitation. Rain Attenuation In Satellite Communication. It is the first Africa geosynchronous communication satellite and is positioned at 42.50 E. 2.1.3 Rain drop distribution Rain attenuation and depolarization occurs because of two reasons: 1) Individual rain drops absorb energy from radio waves (i.e. This research explores the characterization of rain specific attenuation and frequency scaling technique for satellite communication system in Akure (7.17N, 5.18E, 358 m), Nigeria. Introduction. Rain attenuation events are one of the foremost drawbacks in satellite communications, impairing satellite link availability. For example, experimental measurement and methods of analysis are discussed in the book Radiowave Propagation in Satellite Communications by Louis J. Ippolito (Van Nostrand, 1986). lite communications systems requires designers to address and overcome many complex scientific problems. The most classical approach of determining rain attenuation for radio-wave frequency has been to theoretically determine the specific attenuation. The important factor to be considered in the link budget estimation for satellite communication systems, operating at frequencies above 10 GHz is the rain attenuation. the goal of this study has been to perform an evaluation of radio wave . This means that to meet the specified power requirements at the input to the satellite for 99.9 percent of the time, the earth station must be capable of providing a 1.9-dB margin over the clear-sky conditions. The physical quantity used to determine attenuation is rain rate, .

2.1 Satellite Communication System 7 2.1.1 Introduction 7 2.1.2 Satellite Orbits 8 2.1.3 Satellite Visibility 10 2.1.4 Look Angle Determination 11 . The research adopted KM concept for data learning to produce meaningful information for knowledge . It is not necessarily available (for instance in broadcasting systems) and is also a cost and security issue. E. Gutierrez, J. Restrepo, and C. Fradique-Mendez, "Development of rain-attenuation and rain-rate maps for satellite system design in the Ku and Ka bands in Colombia," IEEE Antenna and Propag. Satellite communication system like other systems has some impairments for example, the transmitting and receiving equipment, polarization mismatch losses, di-pointing losses and free- space losses, the first three impairments can be improved and overcome their effects is not . intensity and rain attenuation, for the design of satellite systems in the tropical countries and particularly in Nigeria. It results in scattering and absorption of downlink signals. Scattering and absorption are the main concern for system designers at these frequency bands. meters per second with diameter D by Index Terms satellite communication, propagation R 0.6 10 3 D 3V ( D ) N ( D ) dD mm/hr (2) impairments, rain attenuation, ITU-R model, rain fall rate A. 2000. Satellite communications system operating in frequency band over 10GHz, is restricted in steady operation due to . satellite communication link availability. 1. Crossing the wave through a rain area, a cross polarization e ect appears due to this e ect. Center WC. Rainfall rates at the location of the beacon receivers were recorded. It is mainly dependent on communication. At frequency over 10 GHz, rain and precipitation can influence the attenuation a lot; the effect of atmospheric attenuation between the source and destination over wireless communication is of major concern and a proper site visit and proper method . This has resulted in the need for suitable prediction models that can best provide estimates of attenuation due to rain with available . This question appears in Mumbai University > Satellite Communication and Network subject. In: Proceedings of the 2000 TENCON; 2000; Kuala Lumpur, Malaysia. In this paper, tools for the prediction of rain rate and rain attenuation are presented in the form of contour maps for Nigeria using a massive rainfall data bank of 30 years which are taken from measurements made from the coast . In other case, it may exit through the side. Marks: 5 M. Year: May 2013. satellite communication and network . The inherent drawback of Ka-band satellite system is that increase in signal Higher power can overcome the loss to rain fade. The Ka-band (18-40 GHz) frequency spectrum has gained attention for satellite communication. 211 . Sensors (Basel). intensity and rain attenuation, for the design of satellite systems in the tropical countries and particularly in Nigeria. . Link Power Budgetting 10.Calculation of link margin. The traditional C and Ku bands in satellite communications are getting crowded, So the systems are moving towards higher frequency ranges above 20 GHz. Down link rain attenuation Rain fall introduces attenuation by absorption and scattering of signal energy, and the absorptive attenuation introduces noise.. Component model [8]. 2) Some energy in the wave is scattered out of propagation path. Proc IRE. This implies that the rain can be considered as an isotropic media for the electromagnetic wave propagation. The analysis involved a satellite terminal located in Selangor, Malaysia (Latitude 3.01 N, Longitude 101.6 E), and the was fixed to 45. 1. frequencies of transmission: 12 and 50 GHz. Rain attenuation plays a significant role in satellite communications in the Ka band. Measurements of rain attenuation in Indonesia have been done for satellite communication links in Padang, Cibinong, Surabaya and Bandung. 2. Yagasena A, Hassan SI. 2006).The restrained use of millimeter bands for commercial operations is due to severe rain attenuation. At a rain rate of 47.6 mm/hr, measured by Indian Meteorological Department for 2018 for Gadanki, near Tirupati, India, the attenuation values were . The operation of high speed satellite transmission in the Ka-band (20/30GHz) will therefore be susceptible to rain attenuation in a tropical country such as Nigeria. Evaluation of Ka-Band Rain Attenuation for Satellite Communication in Tropical Regions Through a Measurement of Multiple Antenna Sizes P. M. Kalaivaanan, . The frequency of the satellite signal transmitted during rain events has a significant effect on the amount of signal power attenuation as shown in Figure 6. Rain fade is characterized primarily by the attenuation of the radiofrequency (RF) Satellite communications operating at 10 GHz and above in the tropics suffer severe signal degradation due to rain.Attenuation due to rain at 38 GHz had been measured for a period of 20 months in Malaysia.Analyses carried out include seasonal variations, diurnal effects and the annual cumulative distributions. One year of copolarized signal data from the OLYMPUS satellite's 12, 20, and 30 GHz beacons were examined for frequency scaling of attenuation. It normally shows up when we operate above 10GHz. Some countermeasures for rain attenuation using site and/or satellite diversities are therefore required in order to operate reliable Ka-band satellite communication links. 1948;36(3):353-355. The accumulation of ice, water droplets, and snow on the satellite dish surface may decrease signal strength by up to 15%. the drops are heated). The paper studied the rain attenuation using empirical formulations of the prominent models like ITU-R P.618-13, ITU-R P.838-3, Moupfouma, and Garcia Lopez. In the case of two Earth stations existing, you can use the p618SiteDiversityConfig object to model the parameters required for the calculation of the outage probability due to rain attenuation. A more sophisticated method to dealing with rain fade in satellite communications is adaptive coding and modulation (ACM). The cumulative distributions of . 15. signal propagated for satellite communication at frequency above 10GHz (Nweke 2015). The emergence and development of complex radio access networks have increased spectrum occupancy necessitated by the demand for higher bandwidths. Then, you can use the p618SiteDiversityOutage function, which initializes configuration parameters settings, to calculate the . Since rain attenuation significantly affects microwave satellite communication at frequencies above 10 GHz, we will focus our attention on satellite services in the Ku band and above. Until more recently, uplink power control had limited use, since it required more powerful transmitters - ones that could normally run at lower levels and could be increased in power level on command (i.e . Keywords. Rain attenuation, gas attenuation and depolarization are the major losses along earth station and satellite reduces the strength of the carrier. Rain rate and Rain Attenuation predictions are important in radio system operating at Ku and Ka bands as they affect telecommunication systems performance. 16. Rain Attenuation and Doppler Shift Compensation for Satellite Communications Sooyoung Kim Shin, Kwangjae Lim, Kwonhue Choi, and Kunseok Kang In high-. : Rain attenuation prediction model for satellite communications 3329 tween the Earth terminals and the satellite is required to con-vey the feedback. Effective noise temp of rain as. Nigeria has recently launched her first communication satellite, known as Nigerian Communication Satellite (NIGCOMSAT-1). Satellite communication system operates on the principle of point to point and point to multipoint, with clear view from all form of the rain attenuation at such frequency range is desirable in the planning of a reliable communication system at any location. Rain attenuation is a key limiting factor in the introduction of higher frequency bands into satellite and terrestrial microwave systems. 10 pp. The measurement. Introduction. The statistics of the ratios of attenuation in dB for the frequency pairs 30/20, 20/12, and 30/12 GHz computed at each 0.1 s . The weather conditions that attenuate the light beam are sand storms, rain, snow, or fog. Worst-month rain attenuation statistics for satellite-Earth link design at Ku-band in Malaysia. 2017 Aug 12;17 (8):1864. doi: 10.3390/s17081864. In this paper, tools for the. Satellite Link Frequency 2. "Satellite communication networks", Networks beyond 4G", vol. On the Rain Attenuation of Ku-Band Satellite Signal and Prediction Model at Bangkok, Thailand 1Donekeo Lakanchanh,1Attasit Datsong,2Yoshiaki Moriya,1Narong Hemmakorn and1Nipha Leelaruji 1Faculty of Engineering and Research Center for Communications and Information Technology King Mongkut's Institute of Technology Ladkrabang (KMITL), Bangkok, 10520, Thailand, When the weather improves, ACM technology will also raise the modulation back up to full capacity. For this reason, it is necessary to foresee rain events to avoid an outage of the satellite link. Nigeria has recently launched her first communication satellite, known as Nigerian Communication Satellite (NIGCOMSAT-1). Author: Mercy Shields 3 downloads 0 Views 635KB Size At 12 GHz, the rain attenuation that exceeded . I. Dahman et al. Rain rate and rain attenuation pred ictions are one of the vital steps to be considered when analyzing a microwave satellite communication links at the Ku and Ka bands. 46 . Fig. To adequately estimate rain-induced attenuation and fading, the International Telecommunication Union (ITU) recommends use of rainfall data collected using 1-minute integration time. Find . Attenuation due to clouds and fog. These bands are assigned to direct-to-home (DTH) television (TV) broadcast from GEO satellites and also to two-way broadband services, either with GEO or LEO . Abstract Rain attenuation is a major challenge to microwave satellite communication especially at frequencies above 10 GHz, causing unavailability of signals most of the time. Considerable research has been carried out to model rain attenuation mathematically and to characterize rainfall throughout the world. Two-year archived rain-attenuation data on Ku-Band satellite link over the earth-space path of Akure was used for the study. Mag., Vol. written 6.1 years ago by teamques10 ★ 30k: Rain Attenuation: Water droplets scatter and absorb impinging radiation, causing attenuation. The problem with satellite communication is the inability to guarantee communication during rainfall or when the line of sight is obstructed (Oh et al. in order to estimate the amount of rain attenuation on a satellite-to ground slant path and to design cost effective satellite communication links in tropical regions, an accurate rain attenuation prediction model is essential. Scattering and absorption are the main concern for system designers at these frequency bands. This video contains detailed discussion about topics: 1. 9.06o N and longitude 7.48o E. Rain attenuation and link outages is a predominant challenges for satellite service for both direct to home (DTH) television or broadband internet service [2]. 65, 456-474, 1977 . Evaluation of some rain attenuation prediction models for satellite communication at Ku and Ka bands, Journal of Atmospheric and Solar-Terrestrial Physics, 10.1016/j.jastp.2019.03.005, (2019). For RF and Satellite communication reseach and implementations | Explore the latest full-text research PDFs, articles, conference papers, preprints and more on SATELLITE COMMUNICATION. This will be more crucial in tropical regions . Recommendation ITU-R P.840-5 It is quite equivalent to the rain attenuation method The attenuation values are . World map of koppen . The path attenuation caused by heavy rainfall can result in signals to become indistinguishable from the noise signal of the receiver [ 2 ]. Other techniques require a forecast of the attenuation some . lnutt and Haidara (DAH) rain induced attenuation model [6], the Crane-Global model [7] and the Crane-Two . The statistics of the ratios of Rain attenuation is a significant impairment in terrestrial and satellite communications wave propagation, among other environmental disturbances [] [].Due to the Fourth Industrial Revolution, the demand to transfer the data volume is increasing [].The millimeter-wave (mm-wave) frequency is a viable alternative for creating bandwidth to transfer the higher data volume []. Analogous to the associated "static" rain attenuation model, which yields yearly attenuation predictions and is the subject of part I of this work (NASA Contractor Report #179498, Sept. 19861, this dynamic model is applicable at any location in the world that is . . Rain attenuation is a major challenge to microwave satellite communication espe- cially at frequencies above 10 GHz, causing unavailability of signals most of the time. T rain =T A (1-(1/A)). The difference between the two scenarios is significant. Real-Time Rain Rate Evaluation via Satellite Downlink Signal Attenuation Measurement. Satellite communication systems become increasingly sensitive to weather conditions as their operating frequency increases to avoid electromagnetic spectrum congestion and enhance their capacity. Satellite communication system operates on the principle of point to point and point to multipoint, with clear view from all form of 17.