Recently,unmanned aerial vehicle(UAV)-aided free-space optical(FSO)communication has attracted widespread attentions.However,most of the existing research focuses on communication performance only.The authors investig...Recently,unmanned aerial vehicle(UAV)-aided free-space optical(FSO)communication has attracted widespread attentions.However,most of the existing research focuses on communication performance only.The authors investigate the integrated scheduling of communication,sensing,and control for UAV-aided FSO communication systems.Initially,a sensing-control model is established via the control theory.Moreover,an FSO communication channel model is established by considering the effects of atmospheric loss,atmospheric turbulence,geometrical loss,and angle-of-arrival fluctuation.Then,the relationship between the motion control of the UAV and radial displacement is obtained to link the control aspect and communication aspect.Assuming that the base station has instantaneous channel state information(CSI)or statistical CSI,the thresholds of the sensing-control pattern activation are designed,respectively.Finally,an integrated scheduling scheme for performing communication,sensing,and control is proposed.Numerical results indicate that,compared with conventional time-triggered scheme,the proposed integrated scheduling scheme obtains comparable communication and control performance,but reduces the sensing consumed power by 52.46%.展开更多
In this paper,the performance of a two-way relay (TWR) mixed radio frequency/free space optical (RF/FSO) system with co-channel interference (CCI) is investigated.Different from interference-limited one-way relay (OWR...In this paper,the performance of a two-way relay (TWR) mixed radio frequency/free space optical (RF/FSO) system with co-channel interference (CCI) is investigated.Different from interference-limited one-way relay (OWR) system,CCIs should be considered at both relay and users in TWR system.Additionally,opportunistic user schedule is applied to select the user with the largest signal to interference plus noise ratio (SINR).Exact and asymptotic outage probability (OP) is derived.Approximate bit error rate (BER) is further presented to evaluate the overall performance.Simulation results show that the performance of a TWR system is dominated by the uplink or downlink whose performance is severer.展开更多
Free space optical communication (FSO) proves to be very effective and efficient technology for wireless communication. This work basically deals with the designing of FSO systems. Further, a comparative study has bee...Free space optical communication (FSO) proves to be very effective and efficient technology for wireless communication. This work basically deals with the designing of FSO systems. Further, a comparative study has been made to ascertain which modulation technique proves better for communication. This paper investigates the performance of ASK and PSK modulation based FSO system by varying different FSO parameters under several conditions including haze, rain, mist and fog. Finally, simulation results are analysed and discussed.展开更多
In this paper,we investigate a Recofigurable Intelligent Surface(RIS)-assisted Free-Space Optics-Radio Frequency(FSO-RF)mixed dual-hop communication system for Unmanned Aerial Vehicles(UAVs).In the first hop,a source ...In this paper,we investigate a Recofigurable Intelligent Surface(RIS)-assisted Free-Space Optics-Radio Frequency(FSO-RF)mixed dual-hop communication system for Unmanned Aerial Vehicles(UAVs).In the first hop,a source UAV transmits data to a relay UAV using the FSO technique.In the second hop,the relay UAV forwards data to a destination Mobile Station(MS)via an RF channel,with the RIS enhancing coverage and performance.The relay UAV operates in a Decode-and-Forward(DF)mode.As the main contribution,we provide a mathematical performance analysis of the RIS-assisted FSO-RF mixed dual-hop UAV system,evaluating outage probability,Bit-Error Rate(BER),and average capacity.The analysis accounts for factors such as atmospheric attenuation,turbulence,geometric losses,and link interruptions caused by UAV hovering behaviors.To the best of our knowledge,this is the first theoretical investigation of RIS-assisted FSO-RF mixed dual-hop UAV communication systems.Our analytical results show strong agreement with Monte Carlo simulation outcomes.Furthermore,simulation results demonstrate that RIS significantly enhances the performance of UAV-aided mixed RF/FSO systems,although performance saturation is observed due to uncertainties stemming from UAV hovering behavior.展开更多
In this paper,the eavesdropping model based on eavesdroppers near legitimate users,and the effect of atmospheric channel correlation on the physical layer security(PLS)of the free-space optical(FSO)link are analyzed.A...In this paper,the eavesdropping model based on eavesdroppers near legitimate users,and the effect of atmospheric channel correlation on the physical layer security(PLS)of the free-space optical(FSO)link are analyzed.According to the joint probability density function(PDF)and cumulative distribution function(CDF)of Gamma-Gamma(G-G)distribution,a new closed-form expression of interception probability is derived.Numerical results show that the interception probability of the FSO system depends on turbulence intensity,channel correlation and radial displacement attenuation of eavesdroppers.展开更多
Free space optical(FSO)communication has recently aroused great interest in academia due to its unique features,such as large transmission band,high data rates,and strong anti-electromagnetic interference.With the aim...Free space optical(FSO)communication has recently aroused great interest in academia due to its unique features,such as large transmission band,high data rates,and strong anti-electromagnetic interference.With the aim of evaluating the performance of an FSO communication system and extending the line-of-sight transmission distance,we propose an unmanned aerial vehicle(UAV)-assisted dual-hop FSO communication system equipped with amplifyand-forward protocol at the relay node.Specifically,we consider impairments of atmospheric absorption,pointing errors,atmospheric turbulence,and link interruptions due to angle-of-arrival fluctuations in the relay system.The Gamma-Gamma and Malaga distributions are used to model the influence of atmospheric turbulence on the source-to-UAV and UAVto-destination links,respectively.We derive closedform expressions of the probability density function(PDF)and cumulative distribution function(CDF)for the proposed communication system,in terms of the Meijer-G function.Based on the precise PDF and CDF,analytical expressions for the outage probability,average bit error rate,and ergodic capacity are proposed with the aid of the extended generalized bivariate Fox’s H function.Finally,we show that there is a match between the analytical results and numerical results,and we analyze the influence of the system and channel parameters on the performance.展开更多
Taking into consideration the aperture averaging, the system performance of a point-to-multipoint free space optical(FSO) system for various multiuser diversity scheduling schemes is studied over exponentiated Weibull...Taking into consideration the aperture averaging, the system performance of a point-to-multipoint free space optical(FSO) system for various multiuser diversity scheduling schemes is studied over exponentiated Weibull(EW) fading channels. The selection principles of greedy scheduling(GS), selective multiuser diversity scheduling(SMDS), proportional fair scheduling(PFS) and selective multiuser diversity scheduling with exponential rule(SMDS-ER) schemes are introduced and compared on the basis of time-varying behavior of turbulence channel fading in the present system. The analytical average capacity expressions for the GS and SMDS schemes are derived, respectively. Then, the relative capacity simulations for PFS and SMDS-ER schemes are also provided over EW fading channels with the binary phase shift keying(BPSK) modulation. The results show that the GS scheme obtains the maximum average capacity at the cost of the fairness of users. The SMDS-ER receives the minimum capacity, but it guarantees the fairness of users. The SMDS and PFS schemes can get balance between capacity and fairness. This study can be used for FSO system design.展开更多
Free Space Optical (FSO) communication is one of the most promising access methods. But, the different weather conditions will affect the transceiver performance. In this paper, we build a FSO communication system wit...Free Space Optical (FSO) communication is one of the most promising access methods. But, the different weather conditions will affect the transceiver performance. In this paper, we build a FSO communication system with 16-ary phase shift key-orthogonal frequency division multiplexing (16PSK-OFDM) downstream signals. We analyze the transmission performance of 16PSK-OFDM optical signals under five different weather conditions (sunny, light rain, moderate rain, snow, and fog). The optical spectral diagrams, constellation diagrams, and bit error rate (BER) of the received signals are simulation measured and analyzed. The results show that the constellation diagram under sunny condition is clear, and the value of BER is about 10?4.2 after 16PSK-OFDM optical signals pass through 500 m FSO link. Note that, the constellation points are dispersed under the other weather conditions.展开更多
在深入研究自由空间光通信(FSO Free Space Optical communication)和国内外引信光学装定技术现状的基础上,对实现引信激光装定系统的编码调制技术进行了理论研究,给出一个低功耗、便携式引信激光装定系统设计方案,系统采用半导体激光...在深入研究自由空间光通信(FSO Free Space Optical communication)和国内外引信光学装定技术现状的基础上,对实现引信激光装定系统的编码调制技术进行了理论研究,给出一个低功耗、便携式引信激光装定系统设计方案,系统采用半导体激光器作为光源,采用PIN光敏二极管作为光接收器件,通过RS信道编码、PPM调制及激光驱动电源控制,实现信息在激光载体上的高速率大气传输,最后给出系统的实验结果,探讨了引信激光装定技术的应用前景。展开更多
文摘Recently,unmanned aerial vehicle(UAV)-aided free-space optical(FSO)communication has attracted widespread attentions.However,most of the existing research focuses on communication performance only.The authors investigate the integrated scheduling of communication,sensing,and control for UAV-aided FSO communication systems.Initially,a sensing-control model is established via the control theory.Moreover,an FSO communication channel model is established by considering the effects of atmospheric loss,atmospheric turbulence,geometrical loss,and angle-of-arrival fluctuation.Then,the relationship between the motion control of the UAV and radial displacement is obtained to link the control aspect and communication aspect.Assuming that the base station has instantaneous channel state information(CSI)or statistical CSI,the thresholds of the sensing-control pattern activation are designed,respectively.Finally,an integrated scheduling scheme for performing communication,sensing,and control is proposed.Numerical results indicate that,compared with conventional time-triggered scheme,the proposed integrated scheduling scheme obtains comparable communication and control performance,but reduces the sensing consumed power by 52.46%.
基金supported by the Natural Science Foundation of Jilin Province (No.YDZJ202401626ZYTS)。
文摘In this paper,the performance of a two-way relay (TWR) mixed radio frequency/free space optical (RF/FSO) system with co-channel interference (CCI) is investigated.Different from interference-limited one-way relay (OWR) system,CCIs should be considered at both relay and users in TWR system.Additionally,opportunistic user schedule is applied to select the user with the largest signal to interference plus noise ratio (SINR).Exact and asymptotic outage probability (OP) is derived.Approximate bit error rate (BER) is further presented to evaluate the overall performance.Simulation results show that the performance of a TWR system is dominated by the uplink or downlink whose performance is severer.
文摘Free space optical communication (FSO) proves to be very effective and efficient technology for wireless communication. This work basically deals with the designing of FSO systems. Further, a comparative study has been made to ascertain which modulation technique proves better for communication. This paper investigates the performance of ASK and PSK modulation based FSO system by varying different FSO parameters under several conditions including haze, rain, mist and fog. Finally, simulation results are analysed and discussed.
基金supported in part by the National Research Foundation of Korea(NRF)funded by the Korea government(MSIT)under Grant NRF-2022R1I1A3073740in part by the MSIT(Ministry of Science and ICT),Korea,under the ITRC(Information Technology Research Center)support program(IITP-2024-RS-2024-00436406)supervised by the IITP(Institute for Information&Communications Technology Planning&Evaluation)+1 种基金in part by the Institute for Information and Communications Technology Promotion(IITP)Grant funded by the Korea Government(MSIP,Development of Cube Satellites Based on Core Technologies in Low Earth Orbit Satellite Communications)under Grant RS-2024-00396992in part by the Korea Research Institute for Defense Technology planning and advancement(KRIT)grant,funded by the Korea government(DAPA(Defense Acquisition Program Administration))(21-106-A00-007,Space-Layer Intelligent Communication Network Laboratory,2022).
文摘In this paper,we investigate a Recofigurable Intelligent Surface(RIS)-assisted Free-Space Optics-Radio Frequency(FSO-RF)mixed dual-hop communication system for Unmanned Aerial Vehicles(UAVs).In the first hop,a source UAV transmits data to a relay UAV using the FSO technique.In the second hop,the relay UAV forwards data to a destination Mobile Station(MS)via an RF channel,with the RIS enhancing coverage and performance.The relay UAV operates in a Decode-and-Forward(DF)mode.As the main contribution,we provide a mathematical performance analysis of the RIS-assisted FSO-RF mixed dual-hop UAV system,evaluating outage probability,Bit-Error Rate(BER),and average capacity.The analysis accounts for factors such as atmospheric attenuation,turbulence,geometric losses,and link interruptions caused by UAV hovering behaviors.To the best of our knowledge,this is the first theoretical investigation of RIS-assisted FSO-RF mixed dual-hop UAV communication systems.Our analytical results show strong agreement with Monte Carlo simulation outcomes.Furthermore,simulation results demonstrate that RIS significantly enhances the performance of UAV-aided mixed RF/FSO systems,although performance saturation is observed due to uncertainties stemming from UAV hovering behavior.
基金supported in part by the Fundamental Research Project of Shenzhen(No.JCYJ20200109105216803)。
文摘In this paper,the eavesdropping model based on eavesdroppers near legitimate users,and the effect of atmospheric channel correlation on the physical layer security(PLS)of the free-space optical(FSO)link are analyzed.According to the joint probability density function(PDF)and cumulative distribution function(CDF)of Gamma-Gamma(G-G)distribution,a new closed-form expression of interception probability is derived.Numerical results show that the interception probability of the FSO system depends on turbulence intensity,channel correlation and radial displacement attenuation of eavesdroppers.
文摘Free space optical(FSO)communication has recently aroused great interest in academia due to its unique features,such as large transmission band,high data rates,and strong anti-electromagnetic interference.With the aim of evaluating the performance of an FSO communication system and extending the line-of-sight transmission distance,we propose an unmanned aerial vehicle(UAV)-assisted dual-hop FSO communication system equipped with amplifyand-forward protocol at the relay node.Specifically,we consider impairments of atmospheric absorption,pointing errors,atmospheric turbulence,and link interruptions due to angle-of-arrival fluctuations in the relay system.The Gamma-Gamma and Malaga distributions are used to model the influence of atmospheric turbulence on the source-to-UAV and UAVto-destination links,respectively.We derive closedform expressions of the probability density function(PDF)and cumulative distribution function(CDF)for the proposed communication system,in terms of the Meijer-G function.Based on the precise PDF and CDF,analytical expressions for the outage probability,average bit error rate,and ergodic capacity are proposed with the aid of the extended generalized bivariate Fox’s H function.Finally,we show that there is a match between the analytical results and numerical results,and we analyze the influence of the system and channel parameters on the performance.
基金supported by the National Natural Science Foundation of China(No.61671347)the Natural Science Foundation of Shaanxi Province(No.2016JQ6027)the 111 Project of China(No.B08038)
文摘Taking into consideration the aperture averaging, the system performance of a point-to-multipoint free space optical(FSO) system for various multiuser diversity scheduling schemes is studied over exponentiated Weibull(EW) fading channels. The selection principles of greedy scheduling(GS), selective multiuser diversity scheduling(SMDS), proportional fair scheduling(PFS) and selective multiuser diversity scheduling with exponential rule(SMDS-ER) schemes are introduced and compared on the basis of time-varying behavior of turbulence channel fading in the present system. The analytical average capacity expressions for the GS and SMDS schemes are derived, respectively. Then, the relative capacity simulations for PFS and SMDS-ER schemes are also provided over EW fading channels with the binary phase shift keying(BPSK) modulation. The results show that the GS scheme obtains the maximum average capacity at the cost of the fairness of users. The SMDS-ER receives the minimum capacity, but it guarantees the fairness of users. The SMDS and PFS schemes can get balance between capacity and fairness. This study can be used for FSO system design.
文摘Free Space Optical (FSO) communication is one of the most promising access methods. But, the different weather conditions will affect the transceiver performance. In this paper, we build a FSO communication system with 16-ary phase shift key-orthogonal frequency division multiplexing (16PSK-OFDM) downstream signals. We analyze the transmission performance of 16PSK-OFDM optical signals under five different weather conditions (sunny, light rain, moderate rain, snow, and fog). The optical spectral diagrams, constellation diagrams, and bit error rate (BER) of the received signals are simulation measured and analyzed. The results show that the constellation diagram under sunny condition is clear, and the value of BER is about 10?4.2 after 16PSK-OFDM optical signals pass through 500 m FSO link. Note that, the constellation points are dispersed under the other weather conditions.
文摘在深入研究自由空间光通信(FSO Free Space Optical communication)和国内外引信光学装定技术现状的基础上,对实现引信激光装定系统的编码调制技术进行了理论研究,给出一个低功耗、便携式引信激光装定系统设计方案,系统采用半导体激光器作为光源,采用PIN光敏二极管作为光接收器件,通过RS信道编码、PPM调制及激光驱动电源控制,实现信息在激光载体上的高速率大气传输,最后给出系统的实验结果,探讨了引信激光装定技术的应用前景。
