A novel all-optical bit-error indicating scheme based on self-phase modulation and band-pass filtering is proposed.In this scheme,the amplified original bit stream propagates through a high-nonlinear fiber where self-...A novel all-optical bit-error indicating scheme based on self-phase modulation and band-pass filtering is proposed.In this scheme,the amplified original bit stream propagates through a high-nonlinear fiber where self-phase modulation occurs,and then passes through a band-pass filter to be converted to a bit-error indicating signal.In the bit-error indicating signal,the error bit has the highest peak power,and the "1" and "0" bits have lower ones.At the same time,the bit-error indicating signal is synchronous with the delayed original bit stream.Therefore,the position of the error bit in the original bit stream can be identified by setting only one judge threshold in the bit error indicating signal.The performance of this scheme has been demonstrated for an 80 Gb/s bit-stream with return-to-zero format by simulation.The results show that the proposed scheme can be used for the all-optical bit-error indicating of the super high bit-rate systems with the return-to-zero format.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
基金Supported by the National Natural Science Foundation of China (Grant No. 60377021)Foundation of New Century Excellent Talents in University (Grant No. NCET-07-0152)Sichuan Scientific Funds for Young Researchers (Grant No. 08ZQ026-012)
文摘A novel all-optical bit-error indicating scheme based on self-phase modulation and band-pass filtering is proposed.In this scheme,the amplified original bit stream propagates through a high-nonlinear fiber where self-phase modulation occurs,and then passes through a band-pass filter to be converted to a bit-error indicating signal.In the bit-error indicating signal,the error bit has the highest peak power,and the "1" and "0" bits have lower ones.At the same time,the bit-error indicating signal is synchronous with the delayed original bit stream.Therefore,the position of the error bit in the original bit stream can be identified by setting only one judge threshold in the bit error indicating signal.The performance of this scheme has been demonstrated for an 80 Gb/s bit-stream with return-to-zero format by simulation.The results show that the proposed scheme can be used for the all-optical bit-error indicating of the super high bit-rate systems with the return-to-zero format.
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.
