{"title":"利用 Karasawa 模型测量对流层最低层振幅闪烁的剖面和分布统计数据","authors":"Ayodeji G. Ashidi, Okikiade A. Layioye","doi":"10.1007/s12647-024-00767-w","DOIUrl":null,"url":null,"abstract":"<p>Characterizing the variation dynamics of amplitude scintillation within the lowest layers of the troposphere is important for many communication system applications. It provides fast fade statistics used to determine the non-rain-induced fade margin needed for implementing effective fade mitigation techniques on both terrestrial and satellite radio channels. This study employed three-year in-situ data of primary radio-climatic factors (temperature and relative humidity) and radio channel parameters (frequency, elevation angle, and antenna diameter) for estimating tropospheric amplitude scintillation and evaluating its vertical profile over Akure, Nigeria, using the Karasawa scintillation model. The radio-climatic parameters were measured at five altitudinal layers from the surface to a height of 200 m at 50 m interval on a 220 m-tall mast using a Davis Vantage Pro2 automatic weather station at 30 min interval. The extracted data spanned January 2008 to December 2010 (3 years). Radio link parameters frequency, elevation angle, and antenna diameter, with values of 12.5 GHz, 53°, and 0.9 m, respectively, were employed for the computation of scintillation amplitude (<i>χ</i>) and intensity (<i>σ</i>) along with the weather variables. From the results, the histogram of annual scintillation intensity at all levels was well approximated by the stable probability density function (pdf) distribution model. The magnitude of scintillation intensity was found to be much higher during the rainy season than during the dry season. Minimal differences, between 2 and 8% in magnitude, were observed in the annual averaged amplitude across the levels, but the rainy-dry season dichotomy was conspicuous following monthly analysis. An allowance of 0.5 dB and 0.38 dB is required to counteract the effects of scintillation amplitude fade and enhancement, respectively, at this location.</p>","PeriodicalId":689,"journal":{"name":"MAPAN","volume":null,"pages":null},"PeriodicalIF":1.0000,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Profile Measurement and Distribution Statistics of Amplitude Scintillation Within the Lowest Tropospheric Layers Using Karasawa Model\",\"authors\":\"Ayodeji G. Ashidi, Okikiade A. Layioye\",\"doi\":\"10.1007/s12647-024-00767-w\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>Characterizing the variation dynamics of amplitude scintillation within the lowest layers of the troposphere is important for many communication system applications. It provides fast fade statistics used to determine the non-rain-induced fade margin needed for implementing effective fade mitigation techniques on both terrestrial and satellite radio channels. This study employed three-year in-situ data of primary radio-climatic factors (temperature and relative humidity) and radio channel parameters (frequency, elevation angle, and antenna diameter) for estimating tropospheric amplitude scintillation and evaluating its vertical profile over Akure, Nigeria, using the Karasawa scintillation model. The radio-climatic parameters were measured at five altitudinal layers from the surface to a height of 200 m at 50 m interval on a 220 m-tall mast using a Davis Vantage Pro2 automatic weather station at 30 min interval. The extracted data spanned January 2008 to December 2010 (3 years). Radio link parameters frequency, elevation angle, and antenna diameter, with values of 12.5 GHz, 53°, and 0.9 m, respectively, were employed for the computation of scintillation amplitude (<i>χ</i>) and intensity (<i>σ</i>) along with the weather variables. From the results, the histogram of annual scintillation intensity at all levels was well approximated by the stable probability density function (pdf) distribution model. The magnitude of scintillation intensity was found to be much higher during the rainy season than during the dry season. Minimal differences, between 2 and 8% in magnitude, were observed in the annual averaged amplitude across the levels, but the rainy-dry season dichotomy was conspicuous following monthly analysis. An allowance of 0.5 dB and 0.38 dB is required to counteract the effects of scintillation amplitude fade and enhancement, respectively, at this location.</p>\",\"PeriodicalId\":689,\"journal\":{\"name\":\"MAPAN\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.0000,\"publicationDate\":\"2024-08-14\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"MAPAN\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://doi.org/10.1007/s12647-024-00767-w\",\"RegionNum\":4,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"INSTRUMENTS & INSTRUMENTATION\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"MAPAN","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1007/s12647-024-00767-w","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"INSTRUMENTS & INSTRUMENTATION","Score":null,"Total":0}
Profile Measurement and Distribution Statistics of Amplitude Scintillation Within the Lowest Tropospheric Layers Using Karasawa Model
Characterizing the variation dynamics of amplitude scintillation within the lowest layers of the troposphere is important for many communication system applications. It provides fast fade statistics used to determine the non-rain-induced fade margin needed for implementing effective fade mitigation techniques on both terrestrial and satellite radio channels. This study employed three-year in-situ data of primary radio-climatic factors (temperature and relative humidity) and radio channel parameters (frequency, elevation angle, and antenna diameter) for estimating tropospheric amplitude scintillation and evaluating its vertical profile over Akure, Nigeria, using the Karasawa scintillation model. The radio-climatic parameters were measured at five altitudinal layers from the surface to a height of 200 m at 50 m interval on a 220 m-tall mast using a Davis Vantage Pro2 automatic weather station at 30 min interval. The extracted data spanned January 2008 to December 2010 (3 years). Radio link parameters frequency, elevation angle, and antenna diameter, with values of 12.5 GHz, 53°, and 0.9 m, respectively, were employed for the computation of scintillation amplitude (χ) and intensity (σ) along with the weather variables. From the results, the histogram of annual scintillation intensity at all levels was well approximated by the stable probability density function (pdf) distribution model. The magnitude of scintillation intensity was found to be much higher during the rainy season than during the dry season. Minimal differences, between 2 and 8% in magnitude, were observed in the annual averaged amplitude across the levels, but the rainy-dry season dichotomy was conspicuous following monthly analysis. An allowance of 0.5 dB and 0.38 dB is required to counteract the effects of scintillation amplitude fade and enhancement, respectively, at this location.
期刊介绍:
MAPAN-Journal Metrology Society of India is a quarterly publication. It is exclusively devoted to Metrology (Scientific, Industrial or Legal). It has been fulfilling an important need of Metrologists and particularly of quality practitioners by publishing exclusive articles on scientific, industrial and legal metrology.
The journal publishes research communication or technical articles of current interest in measurement science; original work, tutorial or survey papers in any metrology related area; reviews and analytical studies in metrology; case studies on reliability, uncertainty in measurements; and reports and results of intercomparison and proficiency testing.