{"title":"认知无线网络中AF中继非对称RF-FSO系统容量分析","authors":"M. Torabi, Nasim Mohammadi","doi":"10.1109/WACOWC.2019.8770001","DOIUrl":null,"url":null,"abstract":"This paper presents a performance analysis for the average channel capacity of an asymmetric two-hop cooperative relaying in cognitive-radio system, in which the first hop is a radio-frequency (RF) link and the second hop is a free-space-optical (FSO) communication link. In the considered cognitive radio, the licence spectrum of a primary user (PU)is shared with an unlicensed user, denoted as secondary user (SU), using underlay spectrum-sharing and power control mechanism to keep the interference at the PU receiver side, always below a given threshold. For the FSO link, some practical issues such as pointing errors, and atmospheric turbulence are taken into considerations, where the IM/DD scheme is used for signal detection. It is also assumed that RF and FSO links follow the Rayleigh and the Gamma-Gamma distributions, respectively. To perform a performance analysis, the cumulative distribution function (CDF) of the received signal-to-noise-ratio (SNR) at the SU receiver is presented. Using the CDF expression, a closed-form expression is derived for the average channel capacity of the considered hybrid RF-FSO system. Finally, the numerical results as well as Monte-Carlo simulation results, and discussions are presented.","PeriodicalId":375524,"journal":{"name":"2019 2nd West Asian Colloquium on Optical Wireless Communications (WACOWC)","volume":"312 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":"{\"title\":\"Capacity Analysis of an AF Relaying Asymmetric RF-FSO System in a Cognitive Radio Network\",\"authors\":\"M. Torabi, Nasim Mohammadi\",\"doi\":\"10.1109/WACOWC.2019.8770001\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"This paper presents a performance analysis for the average channel capacity of an asymmetric two-hop cooperative relaying in cognitive-radio system, in which the first hop is a radio-frequency (RF) link and the second hop is a free-space-optical (FSO) communication link. In the considered cognitive radio, the licence spectrum of a primary user (PU)is shared with an unlicensed user, denoted as secondary user (SU), using underlay spectrum-sharing and power control mechanism to keep the interference at the PU receiver side, always below a given threshold. For the FSO link, some practical issues such as pointing errors, and atmospheric turbulence are taken into considerations, where the IM/DD scheme is used for signal detection. It is also assumed that RF and FSO links follow the Rayleigh and the Gamma-Gamma distributions, respectively. To perform a performance analysis, the cumulative distribution function (CDF) of the received signal-to-noise-ratio (SNR) at the SU receiver is presented. Using the CDF expression, a closed-form expression is derived for the average channel capacity of the considered hybrid RF-FSO system. Finally, the numerical results as well as Monte-Carlo simulation results, and discussions are presented.\",\"PeriodicalId\":375524,\"journal\":{\"name\":\"2019 2nd West Asian Colloquium on Optical Wireless Communications (WACOWC)\",\"volume\":\"312 1\",\"pages\":\"0\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2019-04-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"3\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"2019 2nd West Asian Colloquium on Optical Wireless Communications (WACOWC)\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1109/WACOWC.2019.8770001\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"2019 2nd West Asian Colloquium on Optical Wireless Communications (WACOWC)","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/WACOWC.2019.8770001","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Capacity Analysis of an AF Relaying Asymmetric RF-FSO System in a Cognitive Radio Network
This paper presents a performance analysis for the average channel capacity of an asymmetric two-hop cooperative relaying in cognitive-radio system, in which the first hop is a radio-frequency (RF) link and the second hop is a free-space-optical (FSO) communication link. In the considered cognitive radio, the licence spectrum of a primary user (PU)is shared with an unlicensed user, denoted as secondary user (SU), using underlay spectrum-sharing and power control mechanism to keep the interference at the PU receiver side, always below a given threshold. For the FSO link, some practical issues such as pointing errors, and atmospheric turbulence are taken into considerations, where the IM/DD scheme is used for signal detection. It is also assumed that RF and FSO links follow the Rayleigh and the Gamma-Gamma distributions, respectively. To perform a performance analysis, the cumulative distribution function (CDF) of the received signal-to-noise-ratio (SNR) at the SU receiver is presented. Using the CDF expression, a closed-form expression is derived for the average channel capacity of the considered hybrid RF-FSO system. Finally, the numerical results as well as Monte-Carlo simulation results, and discussions are presented.