车联网作为未来智慧交通系统中的重要组成部分,对通信和感知的要求也越来越高。通信感知一体化(Integrated Sensing and Communication,ISAC)作为车联网方向极具潜力的一项技术,因可以解决通信场景下的位置感知问题而引起业内的广泛关...车联网作为未来智慧交通系统中的重要组成部分,对通信和感知的要求也越来越高。通信感知一体化(Integrated Sensing and Communication,ISAC)作为车联网方向极具潜力的一项技术,因可以解决通信场景下的位置感知问题而引起业内的广泛关注。由于城市场景中电磁环境更加随机和不可控,使得当前传统的通信系统架构已经无法满足车-路侧单元(Vehicle-to-Infrastructure,V2I)系统中的通信与感知需求。对此,考虑在传统的V2I系统加入智能反射面(Reconfigurable Intelligent Surface,RIS),将其与ISAC技术结合,构建多径场景下新的被动感知模型。深入分析了在新的被动感知模型下,RIS辅助ISAC通信系统的抗多径性能优化。提出一种大尺寸RIS单元优化分组方法,使部分单元参与信号的反射,并将单元优化分组后的大尺寸RIS与相同单元数的小尺寸RIS进行系统性能对比。仿真结果表明,优化设计大尺寸RIS实现了高于小尺寸RIS大约1.5 bit/s的信号传输效率,在提升系统信号传输性能的同时有效地减少了信道的估计开销。展开更多
Background:Scabies is a very common skin infection in convicts.The SIMSPE Society(SocietItaliana di Medicina e Sanit`a Penitenziaria)has organized and conducted a multicentre,randomized,comparative,parallel group,in...Background:Scabies is a very common skin infection in convicts.The SIMSPE Society(SocietItaliana di Medicina e Sanit`a Penitenziaria)has organized and conducted a multicentre,randomized,comparative,parallel group,investigator-blinded trial to evaluate the efficacy and tolerability of synergized pyrethrins foam(PF)in comparison with benzyl benzoate(BB)lotion.Methods:A total of 240 convicted patients,enrolled in eight National Jail Institutions,with a clinical diagnosis of scabies,were treated with PF(n = 120)for three consecutive days or BB(n = 120)for five consecutive days.Primary study endpoints were the clinical cure rate and the local tolerability.Secondary endpoints were clinical evolution of scabietic lesions and itching intensity.Study outcomes were assessed using appropriate semiquantitative scores at baseline and after 2 and 4 weeks.A second treatment cycle was applied if after 2 weeks the patient was not judged clinically cured.Results:At week 2,a total of 75%(95 %CI:66-82%)and 71%(95%CI:62-78%)of patients showed a complete clinical cure rate in the PF and BB groups,respectively.At week 4,the percentage of totally cured patients increased up to 95%(95%CI:89-97%)and 91%(95%CI:83-94%)in the PF and BB groups,respectively(P = NS between groups).At week 4,5%in the PF group and 9%in the BB group complained of itching.Burning and irritation after treatment applications were more common in the BB group in comparison with the PF group.The tolerability score was better in the PF group in comparison with to BB group(2.9 vs.2.2;P = 0.0001).A total of 95%of patients in the PV group had a good tolerability score(i.e.= 3)in comparison with 41%in the BB group.Conclusion:Our results show that a 3-day treatment with pyrethrins thermofobic foam is at least as effective as a 5-day treatment with benzyl benzoate lotion in convicted subjects with scabies.The foam formulation is better tolerated than the benzyl benzoate lotion.展开更多
This paper investigates how to achieve integrated sensing and communication(ISAC)based on a cell-free radio access network(CF-RAN)architecture with a minimum footprint of communication resources.We propose a new passi...This paper investigates how to achieve integrated sensing and communication(ISAC)based on a cell-free radio access network(CF-RAN)architecture with a minimum footprint of communication resources.We propose a new passive sensing scheme.The scheme is based on the radio frequency(RF)fingerprint learning of the RF radio unit(RRU)to build an RF fingerprint library of RRUs.The source RRU is identified by comparing the RF fingerprints carried by the signal at the receiver side.The receiver extracts the channel parameters from the signal and estimates the channel environment,thus locating the reflectors in the environment.The proposed scheme can effectively solve the problem of interference between signals in the same time-frequency domain but in different spatial domains when multiple RRUs jointly serve users in CF-RAN architecture.Simulation results show that the proposed passive ISAC scheme can effectively detect reflector location information in the environment without degrading the communication performance.展开更多
This paper studies the sensing base station(SBS)that has great potential to improve the safety of vehicles and pedestrians on roads.SBS can detect the targets on the road with communication signals using the integrate...This paper studies the sensing base station(SBS)that has great potential to improve the safety of vehicles and pedestrians on roads.SBS can detect the targets on the road with communication signals using the integrated sensing and communication(ISAC)technique.Compared with vehicle-mounted radar,SBS has a better sensing field due to its higher deployment position,which can help solve the problem of sensing blind areas.In this paper,key technologies of SBS are studied,including the beamforming algorithm,beam scanning scheme,and interference cancellation algorithm.To transmit and receive ISAC signals simultaneously,a double-coupling antenna array is applied.The free detection beam and directional communication beam are proposed for joint communication and sensing to meet the requirements of beamwidth and pointing directions.The joint timespace-frequency domain division multiple access algorithm is proposed to cancel the interference of SBS,including multiuser interference and duplex interference between sensing and communication.Finally,the sensing and communication performance of SBS under the industrial scientific medical power limitation is analyzed and simulated.Simulation results show that the communication rate of SBS can reach over 100 Mbps and the range of sensing and communication can reach about 500 m.展开更多
随着无线网络传输速率需求的日益增大,第六代移动通信系统(the sixth generation of mobile communication system,6G)将向太赫兹频段演进。亟须破解巨容量太赫兹无线通信难题,以开发太赫兹宽带频谱资源,同时实现超高传输速率、超高频...随着无线网络传输速率需求的日益增大,第六代移动通信系统(the sixth generation of mobile communication system,6G)将向太赫兹频段演进。亟须破解巨容量太赫兹无线通信难题,以开发太赫兹宽带频谱资源,同时实现超高传输速率、超高频谱效率、超高能量效率等6G性能目标。本文主要介绍了国内外太赫兹通信发展现状、太赫兹无线通信系统架构与分类、巨容量太赫兹无线通信技术,总结了巨容量太赫兹无线通信研究进展及瓶颈难题,包括太赫兹信号收发与通信系统架构、宽频信号的高效调制与处理、无线与光纤融合、硬件实验系统等。通过分析研究现状,展望了6G太赫兹无线通信未来发展趋势与挑战。展开更多
通信感知一体化(Integrated Sensing and Communication,ISAC)作为6G的关键技术之一,广泛应用于智慧交通、智能家居等领域。随着频谱资源的紧缺、技术发展的融合,促使通信和感知功能的一体化,其中ISAC的波形设计是同时实现高效率通信和...通信感知一体化(Integrated Sensing and Communication,ISAC)作为6G的关键技术之一,广泛应用于智慧交通、智能家居等领域。随着频谱资源的紧缺、技术发展的融合,促使通信和感知功能的一体化,其中ISAC的波形设计是同时实现高效率通信和高精度感知的研究重点。从ISAC技术趋势、波形设计重要性、应用场景和发展现状四方面进行了简要介绍,对以通信为主的波形设计、以感知为主的波形设计和波形复用设计进行了分析总结,阐述了联合波形设计的一体化性能边界以及潜在的一体化波形新型设计方式;并对ISAC波形设计的发展方向进行展望。展开更多
针对通信频谱资源的匮乏以及去蜂窝MIMO在资源利用方面的优势,提出了一种毫米波(millimeter-wave,mmWave)场景下的去蜂窝MIMO通感一体化(intergraded sensing and communication,ISAC)系统。在该系统中,基站为用户提供服务的同时,多天...针对通信频谱资源的匮乏以及去蜂窝MIMO在资源利用方面的优势,提出了一种毫米波(millimeter-wave,mmWave)场景下的去蜂窝MIMO通感一体化(intergraded sensing and communication,ISAC)系统。在该系统中,基站为用户提供服务的同时,多天线用户设备能够主动检测多个目标。研究目标是设计模拟和数字波束形成器,以优化通信和雷达波束形成误差的加权和。研究中考虑了2种功率约束,并采用改进的正交匹配追踪算法和黎曼共轭梯度算法进行优化。对通信频谱效率和雷达波束方向图进行仿真分析,结果表明,混合波束方案能在频谱利用和波束指向方面实现折中的性能,这种方案对于提高系统性能具有潜在的应用前景。展开更多
文摘Background:Scabies is a very common skin infection in convicts.The SIMSPE Society(SocietItaliana di Medicina e Sanit`a Penitenziaria)has organized and conducted a multicentre,randomized,comparative,parallel group,investigator-blinded trial to evaluate the efficacy and tolerability of synergized pyrethrins foam(PF)in comparison with benzyl benzoate(BB)lotion.Methods:A total of 240 convicted patients,enrolled in eight National Jail Institutions,with a clinical diagnosis of scabies,were treated with PF(n = 120)for three consecutive days or BB(n = 120)for five consecutive days.Primary study endpoints were the clinical cure rate and the local tolerability.Secondary endpoints were clinical evolution of scabietic lesions and itching intensity.Study outcomes were assessed using appropriate semiquantitative scores at baseline and after 2 and 4 weeks.A second treatment cycle was applied if after 2 weeks the patient was not judged clinically cured.Results:At week 2,a total of 75%(95 %CI:66-82%)and 71%(95%CI:62-78%)of patients showed a complete clinical cure rate in the PF and BB groups,respectively.At week 4,the percentage of totally cured patients increased up to 95%(95%CI:89-97%)and 91%(95%CI:83-94%)in the PF and BB groups,respectively(P = NS between groups).At week 4,5%in the PF group and 9%in the BB group complained of itching.Burning and irritation after treatment applications were more common in the BB group in comparison with the PF group.The tolerability score was better in the PF group in comparison with to BB group(2.9 vs.2.2;P = 0.0001).A total of 95%of patients in the PV group had a good tolerability score(i.e.= 3)in comparison with 41%in the BB group.Conclusion:Our results show that a 3-day treatment with pyrethrins thermofobic foam is at least as effective as a 5-day treatment with benzyl benzoate lotion in convicted subjects with scabies.The foam formulation is better tolerated than the benzyl benzoate lotion.
基金supported in part by the National Key Research and Development Program under Grant(2021YFB2900300)by the National Natural Science Foundation of China(NSFC)under Grants 61971127,61871122by the Southeast University-China Mobile Research Institute Joint Innovation Center,and by the Major Key Project of PCL(PCL2021A01-2).
文摘This paper investigates how to achieve integrated sensing and communication(ISAC)based on a cell-free radio access network(CF-RAN)architecture with a minimum footprint of communication resources.We propose a new passive sensing scheme.The scheme is based on the radio frequency(RF)fingerprint learning of the RF radio unit(RRU)to build an RF fingerprint library of RRUs.The source RRU is identified by comparing the RF fingerprints carried by the signal at the receiver side.The receiver extracts the channel parameters from the signal and estimates the channel environment,thus locating the reflectors in the environment.The proposed scheme can effectively solve the problem of interference between signals in the same time-frequency domain but in different spatial domains when multiple RRUs jointly serve users in CF-RAN architecture.Simulation results show that the proposed passive ISAC scheme can effectively detect reflector location information in the environment without degrading the communication performance.
基金supported in part by the National Natural Science Foundation of China under Grant U21B2014,Grant 92267202,and Grant 62271081.
文摘This paper studies the sensing base station(SBS)that has great potential to improve the safety of vehicles and pedestrians on roads.SBS can detect the targets on the road with communication signals using the integrated sensing and communication(ISAC)technique.Compared with vehicle-mounted radar,SBS has a better sensing field due to its higher deployment position,which can help solve the problem of sensing blind areas.In this paper,key technologies of SBS are studied,including the beamforming algorithm,beam scanning scheme,and interference cancellation algorithm.To transmit and receive ISAC signals simultaneously,a double-coupling antenna array is applied.The free detection beam and directional communication beam are proposed for joint communication and sensing to meet the requirements of beamwidth and pointing directions.The joint timespace-frequency domain division multiple access algorithm is proposed to cancel the interference of SBS,including multiuser interference and duplex interference between sensing and communication.Finally,the sensing and communication performance of SBS under the industrial scientific medical power limitation is analyzed and simulated.Simulation results show that the communication rate of SBS can reach over 100 Mbps and the range of sensing and communication can reach about 500 m.
文摘随着无线网络传输速率需求的日益增大,第六代移动通信系统(the sixth generation of mobile communication system,6G)将向太赫兹频段演进。亟须破解巨容量太赫兹无线通信难题,以开发太赫兹宽带频谱资源,同时实现超高传输速率、超高频谱效率、超高能量效率等6G性能目标。本文主要介绍了国内外太赫兹通信发展现状、太赫兹无线通信系统架构与分类、巨容量太赫兹无线通信技术,总结了巨容量太赫兹无线通信研究进展及瓶颈难题,包括太赫兹信号收发与通信系统架构、宽频信号的高效调制与处理、无线与光纤融合、硬件实验系统等。通过分析研究现状,展望了6G太赫兹无线通信未来发展趋势与挑战。
文摘通信感知一体化(Integrated Sensing and Communication,ISAC)作为6G的关键技术之一,广泛应用于智慧交通、智能家居等领域。随着频谱资源的紧缺、技术发展的融合,促使通信和感知功能的一体化,其中ISAC的波形设计是同时实现高效率通信和高精度感知的研究重点。从ISAC技术趋势、波形设计重要性、应用场景和发展现状四方面进行了简要介绍,对以通信为主的波形设计、以感知为主的波形设计和波形复用设计进行了分析总结,阐述了联合波形设计的一体化性能边界以及潜在的一体化波形新型设计方式;并对ISAC波形设计的发展方向进行展望。
文摘针对通信频谱资源的匮乏以及去蜂窝MIMO在资源利用方面的优势,提出了一种毫米波(millimeter-wave,mmWave)场景下的去蜂窝MIMO通感一体化(intergraded sensing and communication,ISAC)系统。在该系统中,基站为用户提供服务的同时,多天线用户设备能够主动检测多个目标。研究目标是设计模拟和数字波束形成器,以优化通信和雷达波束形成误差的加权和。研究中考虑了2种功率约束,并采用改进的正交匹配追踪算法和黎曼共轭梯度算法进行优化。对通信频谱效率和雷达波束方向图进行仿真分析,结果表明,混合波束方案能在频谱利用和波束指向方面实现折中的性能,这种方案对于提高系统性能具有潜在的应用前景。
