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research in Astronomy and Astrophysics 2024年第3期24卷 224-236页

作者： ying yang Lan-Qiang Zhang Nan-Fei Yan Jin-Sheng yang Zhen Li Teng-Fei Song Xue-Jun Rao Chang-Hui Rao Key laboratory on Adaptive Optics Chinese Academy of SciencesChengdu 610209China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China School of Electronic Electrical and Communication Engineering of the University of Chinese Academy of SciencesBeijing 100049China university of Chinese Academy of Sciences Beijing 100049China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key laboratory of Modern A&A Ministry of EducationNanjing 210023China Yunnan Observatories Chinese Academy of SciencesKunming 650216.China

The 2.5 m wide-field and high-resolution solar telescope(WeHoST)is currently under developing for solar *** aims to achieve high-resolution observations over a super-wide field of view(FOV)of5′×5′,and a desired resolution of 0.3″.To meet the scientific requirements of WeHoST,the ground-layer adaptive optics(GLAO)with a specially designed wave front sensing system is as the primary *** introduce the GLAO configuration,particularly the wave front sensing *** analytic method,we simulate the performance of both classical AO and GLAO systems,optimize the wave front sensing system,and evaluate GLAO performance in terms of PSF uniformity and correction improvement across whole *** results indicate that,the classical AO will achieve diffraction-limited resolution;the suggested GLAO configuration will uniformly improve the seeing across the full 5′×5′FOV,reducing the FWHM across the axis FOV to less than0.3″(λ≥705 nm,r0≥11 cm),which is more than two times *** specially designed wave front sensor schedule offers new potential for WeHoST’s GLAO,particularly the multi-FOV GLAO and the flexibility to select the detected *** capabilities will significantly enhance the scientific output of the telescope.

关键词： instrumentation adaptive optics-instrumentation detectors-instrumentation high angular resolution-methods numerical-telescopes-Sun activity

离散信号空间上的最小能量框架在升余弦脉冲信号上的去噪算法

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通信学报 2012年第3期33卷 44-51页

作者：谢映海杨维樊婷婷北京交通大学轨道交通控制与安全国家重点实验室北京100044 东南大学移动通信国家重点实验室江苏南京210096

利用离散信号空间上的最小能量(小波)框架对升余弦脉冲信号展开去噪算法的研究。对于所给的2组不同最小能量框架,升余弦脉冲信号和加性高斯白噪声的抽样离散信号在这2组框架的各个子数列下的分解系数将出现明显不同的统计特征。据此给出... 详细信息

利用离散信号空间上的最小能量(小波)框架对升余弦脉冲信号展开去噪算法的研究。对于所给的2组不同最小能量框架,升余弦脉冲信号和加性高斯白噪声的抽样离散信号在这2组框架的各个子数列下的分解系数将出现明显不同的统计特征。据此给出了2个具体的阈值去噪算法,两者都充分利用了最小能量框架在信号去噪应用上的优点,在保持发送原始信号成分的同时去除了部分噪声成分,获得了较好的处理效果。仿真结果表明,当调制方式为BPSK且升余弦脉冲信号受加性高斯白噪声影响时,如果利用2个算法对接收波形进行去噪预处理,则接收信号的信噪比大幅度提升,在误码率上可以分别获得3.1dB和2.7dB左右的性能增益。

关键词：离散信号空间最小能量(小波)框架升余弦脉冲信号阈值去噪算法

Novel multi-path routing scheme for UWB Ad hoc network

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通信学报 2005年第10期26卷 89-96页

作者： XU Ping-ping yang Cai-yu SONG Shu-qing BI Guang-guo national mobile communication research laboratory Southeast University Nanjing 210096 China

The routing protocols play an important role for ad hoc networks *** some problems with DSR,SMR,and AMR protocols were analyzed,a new routing protocol suitable for UWB Ad hoc networks was proposed in this *** new routing protocol utilize an act of orientation of UWB and tries to get sufficient route information and decrease the network load caused by route discovery at the same *** results show that the routing load of the new protocol is lower and throughput is higher than that of *** the node’s mobility increases,these advantages become more obvious.

关键词：多路技术邮件路由 UWB通信动态系统

A compact multi-pixel superconducting nanowire single-photon detector array supporting gigabit space-to-ground communications

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Light(Science & Applications) 2024年第2期13卷 254-266页

作者： Hao Hao Qing-Yuan Zhao yang-Hui Huang Jie Deng Fan yang Sai-ying Ru Zhen Liu Chao Wan Hao Liu Zhi-Jian Li Hua-Bing Wang Xue-Cou Tu La-Bao Zhang Xiao-Qing Jia Xing-Long Wu Jian Chen Lin Kang Pei-Heng Wu research Institute of Superconductor Electronics(RISE) School of Electronic Science and EngineeringNanjing UniversityNanjingJiangsu 210023China Purple Mountain Laboratories NanjingJiangsu 211111China Hefei national laboratory HefeiAnhui 230088China national laboratory of Solid State Microstructures and Department of Physics Nanjing UniversityNanjing 210023China

Classical and quantum space-to-ground communications necessitate highly sensitive receivers capable of extracting information from modulated photons to extend the communication distance from near-earth orbits to deep space *** achieve gigabit data rates while mitigating strong background noise photons and beam drift in a highly attenuated free-space channel,a comprehensive design of a multi-functional detector is *** this study,we present an innovative compact multi-pixel superconducting nanowire single-photon detector array that integrates near-unity detection efficiency(91.6%),high photon counting rate(1.61 Gcps),large dynamic range for resolving different photon numbers(1-24),and four-quadrant position sensing function all within one ***,we have constructed a communication testbed to validate the advantages offered by such an *** 8-PPM(pulse position modulation)format communication experiments,we have achieved an impressive maximum data rate of 1.5 Gbps,demonstrating sensitivities surpassing previous benchmarks at respective *** incorporating photon number information into error correction codes,the receiver can tolerate maximum background noise levels equivalent to 0.8 photons/slot at a data rate of 120 Mbps—showcasing a great potential for daylight operation ***,preliminary beam tracking tests were conducted through open-loop scanning techniques,which revealed clear quantitative dependence indicating sensitivity variations based on beam *** on the device characterizations and communication results,we anticipate that this device architecture,along with its corresponding signal processing and coding techniques,will be applicable in future space-to-ground communication tasks.

关键词： photon supporting correction

A Correlation-Based Stochastic Model for Massive MIMO Channel

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China communications 2024年第1期21卷 175-187页

作者： yang Liu Gang Li Chengxiang Wang national mobile communications research laboratory School of Information Science and EngineeringSoutheast UniversityNanjing 211189China School of Internet of Things Engineering Jiangnan UniversityWuxi 214122China Pervasive communication research Center Purple Mountain LaboratoriesNanjing 211111China

In this paper,the channel impulse response matrix(CIRM)can be expressed as a sum of couplings between the steering vectors at the base station(BS)and the eigenbases at the mobile station(MS).Nakagami distribution was used to describe the fading of the coupling between the steering vectors and the *** measurements were carried out to evaluate the performance of this proposed ***,the physical implications of this model were illustrated and the capacities are *** addition,the azimuthal power spectrum(APS)of several models was ***,the channel hardening effect was simulated and *** showed that the proposed model provides a better fit to the measured results than the other CBSM,i.e.,Weichselberger ***,the proposed model can provide better tradeoff between accuracy and complexity in channel *** CIRM model can be used for massive MIMO design in the future communication system design.

关键词： CBSM channel capacity channel hardening channel modeling massive MIMO

Accelerating BP-Based Iterative Low-Density Parity-Check Decoding by Modified Vertical and Horizontal Processes

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Journal of Southwest Jiaotong university(English Edition) 2009年第4期17卷 275-282页

作者：陈婧文仰枫帆罗琳 THO Le-Ngoc College of Information Science and Technology Nanjing University of Aeronautics and Astronautics College of Information Science and Engineering Southeast University Department of Electrical and Computer Engineering McGill UniversityMontreal

Two modified BP algorithms related to vertical and horizontal processes are proposed to accelerate iterative low-density parity- check （LDPC） decoding over an additive white Gaussian noise （AWGN） channel, where the newly updated extrinsic information is immediately used in the current decoding round. Theoretical analysis and simulation results demonstrate that both the modified approaches provide significant performance improvements over the traditional BP algorithm with almost no additional decoding complexity. The proposed algorithm with modified horizontal process offers even better performance than another algorithm with the modified horizontal process. The two modified BP algorithms are very promising in practical communications since both can achieve an excellent trade-off between the performance and decoding complexity.

关键词： LDPC codes Iterative decoding BP algorithm Extrinsic information Horizontal process Vertical process

Epidemic-Like Proximity-Based Traffic Offloading

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China communications 2015年第10期12卷 91-107页

作者： DONG Wenxiang CHEN Jie yang ying ZHANG Wenyi Department of Electronic Engineering and Information Science University of Science and Technology of China Key laboratory of Wireless-Optical communications Chinese Academy of Sciences

Cellular networks are overloaded due to the mobile traffic surge,and mobile social networks(MSNets) can be leveraged for traffic *** this paper,we study the issue of choosing seed users for maximizing the mobile traffic offloaded from cellular *** introduce a gossip-style social cascade(GSC) model to model the epidemic-like information diffusion process in *** static-case and mobile-case networks,we establish an equivalent view and a temporal mapping of the information diffusion process,*** further prove the submodularity in the information diffusion and propose a greedy algorithm to choose the seed users for traffic offloading,yielding a sub-optimal solution to the NP-hard traffic offloading maximization(TOM) *** are carried out to study the offloading performance,illustrating that the greedy algorithm significantly outperforms the heuristic and random algorithms,and user mobility can help further reduce cellular load.

关键词： cellular traffic offloading graph theory information diffusion mobile social networks proximity-based communication

Towards Near-Field communications for 6G:Challenges and Opportunities

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ZTE communications 2024年第1期22卷 3-15页

作者： LIU Mengyu ZHANG yang JIN Yasheng ZHI Kangda PAN Cunhua southeast university Nanjing 210096China Queen Mary university of London London E14NSUK

Extremely large-scale multiple-input multiple-output(XL-MIMO)and terahertz(THz)communications are pivotal candidate technologies for supporting the development of 6G mobile ***,these techniques invalidate the common assumptions of far-field plane waves and introduce many new *** accurately understand the performance of these new techniques,spherical wave modeling of near-field communications needs to be applied for future ***,the investigation of near-field communication holds significant importance for the advancement of 6G,which brings many new and open research challenges in contrast to conventional far-field *** this paper,we first formulate a general model of the near-field channel and discuss the influence of spatial nonstationary properties on the near-field channel ***,we discuss the challenges encountered in the near field in terms of beam training,localization,and transmission scheme design,***,we point out some promising research directions for near-field communications.

关键词： near-field communications extremely large-scale antenna arrays spatial non-stationarity beam training localization

Low-Complexity Integrated Super-Resolution Sensing and communication with Signal Decimation and Ambiguity Removal

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ZTE communications 2024年第3期22卷 48-55页

作者： DAI Qianglong ZHOU Zhiwen XIAO Zhiqiang ZENG Yong yang Fei CHEN Yan national mobile communications research laboratory Southeast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 211111China Wireless Technology Lab. 2012 LabShanghai Huawei Technolo-gies Co.LtdShanghai 201206China

Integrated sensing and communication(ISAC)is one of the main usage scenarios for 6G wireless *** most efficiently utilize the limited wireless resources,integrated super-resolution sensing and communication(ISSAC)has been recently proposed to significantly improve sensing performance with super-resolution algorithms for ISAC systems,such as the Multiple Signal Classification(MUSIC)***,traditional super-resolution sensing algorithms suffer from prohibitive computational complexity of orthogonal-frequency division multiplexing(OFDM)systems due to the large dimensions of the signals in the subcarrier and symbol *** address such issues,we propose a novel two-stage approach to reduce the computational complexity for super-resolution range estimation *** key idea of the proposed scheme is to first uniformly decimate signals in the subcarrier domain so that the computational complexity is significantly reduced without missing any target in the range ***,the decimation operation may result in range ambiguity due to pseudo peaks,which is addressed by the second stage where the total collocated subcarrier data are used to verify the detected *** with traditional MUSIC algorithms,the proposed scheme reduces computational complexity by two orders of magnitude,while maintaining the range resolution and *** results verify the effectiveness of the proposed scheme.

关键词： ISSAC sparse decimation range ambiguity two-stage approach