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Complete analysis of the maximally hyperentangled state via the weak cross-Kerr nonlinearity

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arXiv 2022年

We present a simple method for the complete analysis of maximally hyperentangled state in polarization and spatial-mode degrees of freedom assisted by the weak cross-Kerr nonlinearity. Our method not only can be used for two-photon hyperentangled Bell state analysis and three-photon hyperentangled Greenberger-Horne-Zeilinger (GHZ) state analysis, but also is suitable for N-photon hyperentangled GHZ state analysis. In our protocols, the bit information of hyperentanglement is read out via the nonlinear interaction, and the phase information is obtained by using linear optical element and single photon detector. This approach is achievable with the current technology, and will be useful for the practical high-capacity quantum communication schemes. © 2022, CC BY.

关键词： Photons

Measuring the Orbital-Angular-Momentum Complex Spectrum of Light with the Fast Fourier Transform

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Physical Review Applied 2023年第1期20卷 014010-014010页

作者： Jialong Zhu Yihua Wu Le Wang Hailong Zhou Shengmei Zhao Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications (NUPT) Nanjing 210003 China School of Information Engineering Suqian University Suqian 223800 China Wuhan National Laboratory for Optoelectronics School of Optical and Electronic Information Huazhong University of Science and Technology Wuhan 430074 China Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education Nanjing China National Laboratory of Solid State Microstructures Nanjing University Nanjing 210093 China

Measuring the orbital-angular-momentum (OAM) complex spectrum of light is very important in OAM-based applications. In this paper, we propose and experimentally demonstrate a simple scheme to measure the OAM complex spectrum of light with the fast Fourier transform (FFT). The light with input OAM modes coaxially interferes with a Gaussian light beam that is generated locally to achieve the intensity distribution of the interference. By subtracting the intensity distribution of the input OAM light from this interference intensity distribution, the OAM complex spectrum can be extracted by employing the FFT transform on the result of the subtraction. In addition, we also present an approach to enlarge the range of detectable OAM modes (from 1 to 50) and analyze the effects of optical alignment and the number of superimposed OAM modes on the measurement results. The proposed scheme is demonstrated in a proof-of-principle experiment, where six superimposed OAM modes can be measured without error, with their average deviation of amplitude and phase being 0.07 and 0.308, respectively. The proposed scheme can exploit applications in some advanced domains, including OAM sensing, OAM imaging, optical communication decoding, and various other OAM-based systems.

关键词： Angular momentum of light Metrology Spatial profiles of optical beams Optical sources & detectors Optical spectroscopy

Precoding and Destination-Aided Cooperative Jamming in MIMO Untrusted Relay Systems

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Precoding and Destination-Aided Cooperative Jamming in MIMO ...

IEEE International Conference on communications in China (ICCC)

作者： Luyuan Zhang Hang Long Li Huang Wireless Signal Processing and Network Lab Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing China

ISBN: (数字)9781728173276

ISBN: (纸本)9781728173283

In this paper, secrecy communications with cooperative jamming in a two-hop one-way untrusted relay system is studied. Assuming that all nodes are equipped with multiple antennas, new precoding designs are proposed to increase the secrecy capacity. Two situations are considered, namely only designing precoding vector for jamming signal when user signal has been determined, and designing precoding vectors for both user and jamming signals by jointly considering the source node. For each situation, two alignment algorithms are proposed, namely zero-forcing-based (ZF) alignment algorithm and minimum-mean-squared-error-based (MMSE) alignment algorithm. Both algorithms are designed to ensure that the equivalent wiretap channel matrix forms two aligned vectors. The channel vector from the destination node is designed to be aligned with that from the source node, so that the eavesdropping node cannot decode user signals. Analytical and simulation results show that all proposed scheme can achieve secure communication, and the MMSE algorithm performs better than the ZF. In addition, the destination-relay link has greater impact on the secrecy performance than the relay-destination link.

关键词： Precoding Simulation Security Jamming Relays MIMO communication signal to noise ratio

Fast Neighbor Discovery for wireless Ad Hoc network with Successive Interference Cancellation

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arXiv 2023年

作者： Wei, Zhiqing Liang, Yueyue Meng, Zeyang Feng, Zhiyong Han, Kaifeng Wu, Huici Key Laboratory of Universal Wireless Communications Ministry of Education School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing100876 China The National Engineering Lab for Mobile Network Technologies Beijing University of Posts and Telecommunications Beijing100876 China The China Academy of Information and Communications Technology Beijing100191 China

Neighbor discovery (ND) is a key step in wireless ad hoc network, which directly affects the efficiency of wireless networking. Improving the speed of ND has always been the goal of ND algorithms. The classical ND algorithms lose packets due to the collision of multiple packets, which greatly affects the speed of the ND algorithms. Traditional methods detect packet collision and implement retransmission when encountering packet loss. However, they does not solve the packet collision problem and the performance improvement of ND algorithms is limited. In this paper, the successive interference cancellation (SIC) technology is introduced into the ND algorithms to unpack multiple collision packets by distinguishing multiple packets in the power domain. Besides, the multi-packet reception (MPR) is further applied to reduce the probability of packet collision by distinguishing multiple received packets, thus further improving the speed of ND algorithms. Six ND algorithms, namely completely random algorithm (CRA), CRA based on SIC (CRA-SIC), CRA based on SIC and MPR (CRA-SIC-MPR), scan-based algorithm (SBA), SBA based on SIC (SBA-SIC), and SBA based on SIC and MPR (SBA-SIC-MPR), are theoretically analyzed and verified by simulation. The simulation results show that SIC and MPR reduce the ND time of SBA by 69.02% and CRA by 66.03% *** Codes 60B99, 94A99 Copyright © 2023, The Authors. All rights reserved.

关键词： Internet of things

Symbol-level Integrated Sensing and communication enabled Multiple Base Stations Cooperative Sensing

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arXiv 2023年

作者： Wei, Zhiqing Xu, Ruizhong Feng, Zhiyong Wu, Huici Zhang, Ning Jiang, Wangjun Yang, Xiaoyu The Key Laboratory of Universal Wireless Communications Ministry of Education School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing100876 China The National Engineering Lab for Mobile Network Technologies Beijing University of Posts and Telecommunications Beijing100876 China The Department of Electrical and Computer Engineering University of Windsor WindsorONN9B 3P4 Canada

With the support of integrated sensing and communication (ISAC) technology, mobile communication system will integrate the function of wireless sensing, thereby facilitating new intelligent applications such as smart city and intelligent transportation. Due to the limited sensing accuracy and sensing range of single base station (BS), multi-BS cooperative sensing can be applied to realize high-accurate, long-range and continuous sensing, exploiting the specific advantages of large-scale networked mobile communication system. This paper proposes a cooperative sensing method suitable to mobile communication systems, which applies symbol-level sensing information fusion to estimate the location and velocity of target. With the demodulation symbols obtained from the echo signals of multiple BSs, the phase features contained in the demodulation symbols are used in the fusion procedure, which realizes cooperative sensing with the synchronization level of mobile communication system. Compared with the signal-level fusion in the area of distributed aperture coherence-synthetic radars, the requirement of synchronization is much lower. When signal-to-noise ratio (SNR) is -5 dB, it is evaluated that symbol-level multi-BS cooperative sensing effectively improves the accuracy of distance and velocity estimation of target. Compared with single-BS sensing, the accuracy of distance and velocity estimation is improved by 40% and 72%, respectively. Compared with data-level multi-BS cooperative sensing based on maximum likelihood (ML) estimation, the accuracy of location and velocity estimation is improved by 12% and 63%, respectively. This work may provide a guideline for the design of multi-BS cooperative sensing system to exploit the widely deployed networked mobile communication system. Copyright © 2023, The Authors. All rights reserved.

关键词： Base stations

Multi-Ring on-Chip Interconnected Architecture for Spiking Neural network Hardware Implementations 22

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Multi-Ring on-Chip Interconnected Architecture for Spiking N...

22nd IEEE International Conference on High Performance Computing and communications, 18th IEEE International Conference on Smart City and 6th IEEE International Conference on Data Science and Systems, HPCC-SmartCity-DSS 2020

作者： Liu, Junxiu Jiang, Dong Luo, Yuling Qiu, Senhui Guangxi Normal University School of Electronic Engineering Guilin China Guangxi Key Lab of Multi-source Information Mining Security Guilin China Guangxi Key Laboratory of Wireless Wideband Communication and Signal Processing Guilin China

ISBN: (纸本)9781728176499

Spiking Neural network (SNN) is an artificial intelligence approach inspired by mammalian brain. Recent research has explored SNNs in network-on-Chip (NoC) electronic circuits with the aim to deal with spatiotemporal dynamic tasks in real time. For the NoC-based hardware SNNs, their interconnections are suffering from large area overhead and power consumption due to the numerous buffers and complex structures of routers. This paper presents a novel Multi-Ring Interconnected Architecture (MRIA) to address this problem. Specifically, multiple unidirectional ring topologies are incorporated in MRIA to simplify the routers' crossbar switches, control logic and routing calculation units, and to decrease the interconnections' hardware area and power consumption. In addition, many buffers are also eliminated to further reduce interconnection costs. Experimental results demonstrate that compared to prior approaches, the proposed MRIA achieves average 20.3X and 7.9X reductions for the router area and power, respectively. Meantime, a high throughput of two million spikes per second is obtained. © 2020 IEEE.

关键词： Neural networks

Complete hyperentangled Greenberger-Horne-Zeilinger state analysis for polarization and time-bin hyperentanglement

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arXiv 2022年

We present an efficient scheme for the complete analysis of hyperentangled Greenberger-Horne-Zeilinger (GHZ) state in polarization and time-bin degrees of freedom with two steps. First, the polarization GHZ state is distinguished completely and nondestructively, resorting to the controlled phase flip (CPF) gate constructed by the cavity-assisted interaction. Subsequently, the time-bin GHZ state is analyzed by using the preserved polarization entanglement. With the help of CPF gate and self-assisted mechanism, our scheme can be directly generalized to the complete Nphoton hyperentangled GHZ state analysis, and it may have potential applications in the hyperentanglement-based quantum communication. © 2022, CC BY.

关键词： Polarization

Fault Diagnosis and Location based on Graph Neural network in Telecom networks

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Fault Diagnosis and Location based on Graph Neural Network i...

International Conference on networking and network Applications (NaNA)

作者： Jiajin He Hui Zhao Wireless Signal Processing and Networks (WSPN) Lab Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications (BUPT) Beijing China Key Laboratory of Universal Wireless Communications Beijing China

ISBN: (数字)9781728189543

ISBN: (纸本)9781728189550

As the scale of telecom networks continues to expand and the structure becomes more complex, telecom networks generate a large number of continuous warning messages every day. It may lead to massive network paralysis. To solve this problem, this paper proposes a fault diagnosis scheme of telecom networks based on Graph Neural network (GNN). The scheme can be applied to locate the fault-root-devices. Firstly, Long Short-Term Memory (LSTM) is used to cluster the state level of partial devices, and the results provide prior information for the construction of the GNN. Then, the embedded representation of graph network is introduced to aggregate the information of the whole graph. Finally, the device network is set up and the data information is embedded into the whole graph network. GNN model is built to diagnose the fault of all devices and locate the fault- root-devices. Moreover, the performance of the model constructed respectively by Graph Convolutional network (GCN) and Graph Attention network (GAT) are compared and analyzed. Based on public fault data, the experimental results show that the accuracy of GAT is higher than that of GCN; the correct rate of fault diagnosis can exceed 93 %; and the fault- root-devices can be accurately located. In addition, the complexity is only O(n) in our scheme.

关键词： Fault diagnosis Performance evaluation Analytical models Graph neural networks Telecommunications Complexity theory Paralysis

Probe Selection and Power Weighting for MIMO OTA Testing with Multiple Users 19

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Probe Selection and Power Weighting for MIMO OTA Testing wit...

19th IEEE International Conference on communication Technology, ICCT 2019

作者： Zhe, Shitong Xin, Lijian Li, Yong Wei, Guiming Beijing University of Posts and Telecommunications Wireless Signal Processing and Network Laboratory Key Laboratory of Universal Wireless Communications Ministry of Education Beijing China China Academy of Information and Communications Technology Beijing China

ISBN: (纸本)9781728105352

This paper discusses multiple-input multiple-output (MIMO) over-the-air (OTA) test for multiple users based on multi-probe anechoic chamber (MPAC) method. The spatial correlation is used as a criterion to evaluate the accuracy of the reconstructed channel model. In order to test multiple user equipments (UEs) at the same time and reproduce the target channel model more accurately, the number of channel emulators and probes needs to be increased, which will increase the testing system cost. However, the traditional algorithm can not minimize the correlation error between the real radio environment and the emulated channel environment very well because it substitutes the sum of power angular spectrums (PASs) for multiple users into the optimization function. Given this problem, a novel MIMO OTA optimization method for multiple users is proposed in this paper, which directly balances the probe position according to the different mean angles-of-arrival (AoAs) of each user and minimizes the sum of correlation errors for all users. Moreover, the simulation results show that the proposed method is superior to the traditional and reference algorithm. © 2019 IEEE.

关键词： Probes