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    25 September 2023, Volume 44 Issue 9
    Papers
    Unified ultraviolet communication and sensing:modeling and system optimization
    Chen GONG, Yuchen PAN, Zhengyuan XU
    2023, 44(9):  1-11.  doi:10.11959/j.issn.1000-436x.2023146
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    Currently, there exist few communication works which combine with sensing.It is necessary to build up a unified communication and sensing signal model and system joint design optimization framework.Based on this, a unified ultraviolet communication and sensing framework was proposed, consisting of a transmitter, a sensing detector and a communication receiver.The transmitter sent modulated signals to the communication receiver for information transmission.Due to the non-line of sight scattering effect, certain components of the transmitted signals reached the unknown target which further reflected to the sensing detector for target detection.Two performance metrics for communication and sensing were considered, including the mutual information between the transmitted symbol and the signal at the communication receiver, and the miss detection probability for the target detector.The relationship between the two metrics and the transmission parameters was further analyzed, including the transmission power for the high-level signal, the transmission power for the low-level signal, and the prior probabilities.The results demonstrate a tradeoff between the communication performance metric and sensing performance metric.It is also shown that the power for the high-level signal should be set to be the peak power, and the power for the low-level signal and the prior probabilities should be optimized, to minimize the miss detection probability given a lower bound on the mutual information.

    Spectrum allocation algorithm based on multi-agent reinforcement learning in smart grid
    Feng YAN, Xiaowei LIN, Zhenghao LI, Xia XU, Weiwei XIA, Lianfeng SHEN
    2023, 44(9):  12-24.  doi:10.11959/j.issn.1000-436x.2023179
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    In view of the fact that 5G networks are used to meet the service requirements of various power terminals in smart grid, a spectrum allocation algorithm based on multi-agent reinforcement learning was proposed.Firstly, for the integrated access backhaul system deployed in smart grid, considering the different communication requirements of services in lightweight and non-lightweight terminal, the spectrum allocation problem was formulated as a non-convex mixed-integer programming aiming to maximize the overall energy efficiency.Secondly, the above problem was modeled as a partially observable Markov decision process and transformed into a fully cooperative multi-agent problem, then a spectrum allocation algorithm was proposed which was based on multi-agent proximal policy optimization under the framework of centralized training and distributed execution.Finally, the performance of the proposed algorithm was verified by simulation.The results show that the proposed algorithm has a faster convergence speed and can increase the overall transmission rate by 25.2% through effectively reducing intra-layer and inter-layer interference and balancing the access and backhaul link rates.

    Low-complexity ATPM-VSIMM algorithm with adaptive model parameters
    Hao ZENG, Wangqiang MU, Yang JIANG, Shunping YANG
    2023, 44(9):  25-35.  doi:10.11959/j.issn.1000-436x.2023186
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    Aiming at the problem that for maneuvering target tracking, the accuracy of tracking degraded in interacting multiple model algorithms due to the fixed model sets and the fixed transition probability matrix, a low-complexity ATPM-VSIMM algorithm was proposed, which could update the model parameters adaptively.The maneuvering situation of the target was judged according to the innovation changes of the system, and the state noise of the model sets was adjusted to realize the adaptive update of the model sets.Then, the more accurate transition probability matrix was computed through the change of the model posterior probability and the inter-model switching relationship.Therefore, the matching degree between the system motion model and the target motion trajectory was improved.Finally, the high filtering accuracy and the fast response speed of the tracking system were guaranteed.The effectiveness of the proposed algorithm was verified through three aspects that are the initial value of the model posterior probability, the initial value of the transition probability matrix, and the state noise.Simulation results demonstrate that the filtering accuracy of the ATPM-VSIMM algorithm is improved about 8% compared with the existing algorithms.

    Fast panoramic image stitching algorithm based on parameter regression
    Fan GUO, Xiaohu LI, Wentao LIU, Jin TANG
    2023, 44(9):  36-47.  doi:10.11959/j.issn.1000-436x.2023182
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    In reality, the field of view of images acquired by cameras was usually limited, and the demand for panoramic images was increasing.Therefore, a fast panoramic image stitching algorithm based on parameter regression was proposed for panoramic image sequences.The traditional image registration task was transformed into deep learning combined with machine learning, a multi-scale deep convolutional neural network (MDCNN) based on Gaussian difference pyramid was designed to extract features of stitching images, and LightGBM regression model was used to predict stitching parameters.The transformation matrix and the focal length of the camera were obtained to align the images, and a hyperbolic image fusion algorithm was designed to eliminate the stitching seam between the images.The experimental results show that the proposed algorithm can quickly mosaic images and obtain clearer and more natural panoramic mosaic effects than the existing representative algorithms.It also has good adaptability for infrared images.

    High capacity reversible hiding in encrypted domain based on cipher-feedback secret sharing
    Minqing ZHANG, Chao JIANG, Fuqiang DI, Zongbao JIANG, Xiong ZHANG
    2023, 44(9):  48-57.  doi:10.11959/j.issn.1000-436x.2023170
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    To improve the security, robustness and embedding rate of reversible hiding in encrypted domain in the distributed environment, a multiple embedding algorithm based on cipher-feedback secret sharing was proposed.Firstly, the additional data were embedded into the polynomial coefficients redundancy generated in the process of secret image sharing.Secondly, the extra secrets were embedded by using the additive homomorphism of secret sharing.Experimental results demonstrate that a better security and robustness has been obtained by improving the diffusion characteristic of secret sharing using the feedback mechanism.In the (3,4) and (3,5) threshold, the embedding rates can reach 6.00 bit per pixel and 4.80 bit per pixel respectively.The proposed algorithm can not only maintain the strong security and separability, but also obtain a better embedding capacity.Meanwhile, the embedding rate of the scheme is not affected by the carrier image and is only related to the selection of algorithm parameters.

    Research on interleaved training for massive MIMO downlink with multi-user zero-forcing precoding
    Cheng ZHANG, Minjie DING, Chang LIU, Jing Yindi, Fei YU, Yongming HUANG
    2023, 44(9):  58-69.  doi:10.11959/j.issn.1000-436x.2023163
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    To solve the channel acquisition overhead problem of frequency division duplex massive MIMO, for the typical scenario of zero-forcing (ZF) precoding at the base station with users’ quality of service guarantee, a supervisory mechanism for the signal-to-interference-and-noise ratio (SINR) was introduced, and a multi-user antenna-by-antenna interleaved training scheme was designed.Then, considering the additional time overhead introduced by the interleaved training, a multi-user interleaved training scheme based on antenna grouping was designed.Closed-form expressions of the average training length, transmission success rate, and average effective sum spectrum efficiency were derived for the proposed schemes.Theoretical and simulation results reveal the impact of transmit power, SINR threshold, user number, group length, and the error level of channel on the performance of the proposed schemes, and demonstrate that the proposed schemes significantly reduce the pilot overhead and improve the transmission success rate compared to the full and partial training.

    Research on IoV resource allocation algorithm assisted by reconfigurable intelligent surface
    Fatang CHEN, Ruofan ZHANG
    2023, 44(9):  70-78.  doi:10.11959/j.issn.1000-436x.2023145
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    In order to meet the higher requirements of vehicle communication quality and spectral efficiency, a IoV resource allocation algorithm assisted by reconfigurable intelligent surface (RIS) was proposed.The RIS reflection coefficient matrix, power allocation, and spectrum sharing schemes were combined to solve the problem of maximizing the total capacity of V2I link under the condition of ensuring the reliability of V2V link.As this problem was a non-convex optimization problem with highly coupled variables, it was difficult to solve it directly.Therefore, after introducing an analytic expression to approximate the interrupt probability of V2V link, the problem was decomposed into three sub-problems by using the block coordinate descent (BCD) method, and the sub-problems were solved by introducing auxiliary variables, successive convex approximation (SCA), Hungarian algorithm, etc., and then the approximate suboptimal solution of the problem was obtained.Simulation results show that the proposed algorithm has good convergence performance and can effectively improve the total capacity of V2I link.

    Design and optimization for wireless-powered IRS-aided mobile edge computing system
    Dong TANG, Xuwei HUANG, Zhiwei LUO, Sai ZHAO, Gaofei HUANG
    2023, 44(9):  79-92.  doi:10.11959/j.issn.1000-436x.2023165
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    A new design of intelligent reflecting surface (IRS)-aided mobile edge computing (MEC) system was studied, which consisted of a hybrid access point (HAP) connected with an MEC server, an IRS equipped with radio-frequency (RF) energy harvesting (EH) circuits, and a user side with random task arrival.To reduce energy consumption at the user, a novel protocol was proposed first, in which the system was enabled to select a proper operation mode among an EH mode, an IRS-aided task offloading mode, and an IRS-inactive task offloading mode.Then, based on the proposed protocol, an optimization problem was formulated, which aimed at minimizing the amount of consumed energy at the user by optimizing the selection of system operation mode and the resource allocation in each mode.Lyapunov optimization framework was employed to solve the problem to achieve a low-complexity and efficient optimization algorithm.Simulation results show that the proposed scheme can save 50% to 90% of energy consumption for the MEC system as compared with the existing baseline schemes.

    Low frequency acoustic source imaging method based on coprime position non-synchronous measurement
    Juan WEI, Yutao HE, Fangli NING
    2023, 44(9):  93-103.  doi:10.11959/j.issn.1000-436x.2023166
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    In order to solve the problem that the acoustic imaging resolution was low under the condition of low frequency and low SNR due to the limited microphone array aperture and element density, a high resolution imaging method of low frequency and low SNR sound source was proposed based on the non-synchronous measurement of the coprime position.Firstly, the acoustic signal was received at the coprime position and the missing cross-spectrum matrix was calculated by the mobile prototype array.Then, the improved accelerated proximity gradient algorithm was used to complete the missing cross-spectrum matrix, and the complete cross-spectrum matrix was vectorized.Finally, the virtual array signal model was established and solved.The simulation results demonstrate that the proposed method has lower positioning error, higher imaging resolution, and better robustness and noise immunity than the previous methods under the condition of low frequency and low SNR.

    Adaptive pilot design for OFDM based on deep reinforcement learning
    Qiaoshou LIU, Xiong ZHOU, Shuang LIU, Yifeng DENG
    2023, 44(9):  104-114.  doi:10.11959/j.issn.1000-436x.2023169
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    For orthogonal frequency division multiplexing (OFDM) systems, an adaptive pilot design algorithm based on deep reinforcement learning was proposed.The pilot design problem was formulated as a Markov decision process, where the index of pilot positions was defined as actions.A reward function based on mean squared error (MSE) reduction strategy was formulated, and deep reinforcement learning was employed to update the pilot positions.The pilot was adaptively and dynamically allocated based on channel conditions, thereby utilizing channel characteristics to combat channel fading.The simulation results show that the proposed algorithm has significantly improved channel estimation performance compared with the traditional pilot uniform allocation scheme under three typical multipath channels of 3GPP.

    Graph neural network-based address classification method for account balance model blockchain
    Zhiyuan LI, Binglei XU, Yingyi ZHOU
    2023, 44(9):  115-126.  doi:10.11959/j.issn.1000-436x.2023173
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    To regulate the transactional activities on the public blockchain involving account balance models, it is necessary to conduct research on address classification for transactions on such blockchains.A blockchain address classification method, named AJKGS-ABCM (attention jumping knowledge graph SAGE account-based blockchain classification model), was proposed to categorize blockchain addresses, providing effective support for blockchain transaction tracking.Blockchain transaction data was represented as a graph structure, with addressed as nodes and transactions as edges.The AJK-GraphSAGE algorithm was introduced to learn embedded representations of the graph, where the model’s input required only nodes and their sampled neighboring node sets.Simultaneously, attention mechanisms and skip-connection knowledge integration strategies were incorporated into the model, allowing for adaptive weight allocation across different layers and information sharing between various levels, thereby enhancing training speed and generalization capabilities.Finally, experimental comparisons are conducted, demonstrating superior performance in terms of accuracy, recall, and F1 score compared to other methods.

    Dual functional radar communication based on serial time division CC-CDMA
    Yubo LI, Jian CUI, Junchao FENG, Xiaoyu CHEN
    2023, 44(9):  127-138.  doi:10.11959/j.issn.1000-436x.2023183
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    In order to improve the performance of target detection and solve the problem of self-interference and mutual interference between multiple targets and multiple users, a radar communication integration system based on serial time division CC-CDMA was proposed.Firstly, the code division multiplexing mechanism was used to adjust the spread spectrum sequence of different subcodes in the complementary code to the signals on different time slices at the transmitter through the generalized PTM sequence to generate the integrated signal of radar communication.Secondly, the receiving end of the radar processed the data twice, and the point-by-point minimization method was used to fuse the processing results to improve the target detection capability of the radar subsystem.Lastly, at the receiving end of communication, the subcodes corresponding to the spread spectrum sequence at the transmitting end were used to de-amplify the received signals, and the bit error ratio was further reduced by interleaved coding and Hamming coding.Simulation results show that compared with other radar communication integration systems, the proposed system has lower bit error rate, higher Doppler resolution and better side lobe suppression performance.

    Near-field microwave imaging and quantitative characterization of defects in PE pipeline
    Mingshi LUO, Mengmeng ZHANG, Yang FANG
    2023, 44(9):  139-148.  doi:10.11959/j.issn.1000-436x.2023180
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    In order to effectively detect internal defects in polyethylene (PE) pipeline, microwave non-destructive testing technology was used to detect and quantify defects in PE pipelines.A clutter suppression imaging enhancement method based on principal component analysis (PCA) was proposed for extracting defect images from PE pipelines.Threshold segmentation techniques were used to extract defect features from the enhanced images.Experimental results demonstrate that the proposed method can effectively image PE pipelines and highlight defects.The imaging quality is superior to that of images without clutter suppression.Compared to theoretical values, the average relative error in defect localization is 2.38 mm, and the relative error in area quantification is 13.25%.

    mVulSniffer: a multi-type source code vulnerability sniffer method
    Xuejun ZHANG, Fenghe ZHANG, Jiyang GAI, Xiaogang DU, Wenjie ZHOU, Teli CAI, Bo ZHAO
    2023, 44(9):  149-160.  doi:10.11959/j.issn.1000-436x.2023184
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    Given the problem that the code slice used by existing deep learning-based vulnerability sniffer methods could not comprehensively encompass the subtle characteristics between vulnerability classes, and a single deep learning sniffer model had insufficient ability to learn long context-dependent information between cross-file and cross-function code statements, a multi-type source code vulnerability sniffer method was proposed.Firstly, fine-grained two-level slices containing the types of vulnerabilities were extracted based on the control dependency and data dependency information in program dependency graph.Secondly, the two-level slices were transformed into initial feature vector.Finally, a fusion model of deep learning vulnerability sniffer suitable for two-level slices was constructed to achieve accurate vulnerability detection of multi-type source code.The experimental results on multiple synthetic datasets and two real datasets show that the proposed method outperforms the existing multi-type source code vulnerability sniffer methods.

    Honeypot contract detection method for Ethereum based on source code structure and graph attention network
    Youwei WANG, Yudong HOU, Lizhou FENG
    2023, 44(9):  161-172.  doi:10.11959/j.issn.1000-436x.2023178
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    To address the problems of low accuracy and poor generalization of current honeypot contract detection methods, a honeypot contract detection method for Ethereum based on source code structure and graph attention network was proposed.Firstly, in order to extract the structural information of the Solidity source code of the smart contract, the source code was parsed and converted into an XML parsing tree.Then, a set of feature words that could express the structural and content characteristics of the contract was selected, and the contract source code structure graph was constructed.Finally, in order to avoid the impact of dataset imbalance, the concepts of teacher model and student model were introduced based on the ensemble learning theory.Moreover, the graph attention network model was trained from the global and local perspectives, respectively, and the outputs of all models were fused to obtain the final contract detection result.The experiments demonstrate that CSGDetector has higher honeypot detection capability than the existing method KOLSTM, with increments of 1.27% and 7.21% on F1 measurement in two-class classification and multi-class classification experiments, respectively.When comparing with the existing method XGB, the average recall rate of CSGDetector in the masked honeypot detection experiments for different types of honeypot contracts is improved by 7.57%, which verifies the effectiveness of the method in improving the generalization performance of the algorithm.

    Comprehensive Reviews
    6G knowledge system construction: academic knowledge mining and on-demand application for full domains and omni scenarios
    Zifan SHA, Nan CHENG, Yilong HUI, Wenwei YUE, Yuchuan FU, Ruijin SUN
    2023, 44(9):  173-187.  doi:10.11959/j.issn.1000-436x.2023181
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    At present, the concepts related to 6G have not been unified, and there is an urgent need for consistent cognition and definition.Academics and industries lack a clear understanding of the overall development of 6G and the research progress in related fields.Therefore, the 6G knowledge base and knowledge system was constructed.Firstly, the existing 6G academic documents were automatically screened and stored in a structured way.Secondly, a 6G knowledge base was constructed on the basis of labeling and standardizing text data.In addition, a comprehensive statistical analysis was conducted across all domains of 6G based on the knowledge base and the technologies such as natural language processing, deep neural network and latent tree model were used to realize the extraction and generation of 6G knowledge.Finally, on the basis of large-scale model training, the on-demand knowledge application was realized for diversified service requirements.

    Survey on privacy protection indoor positioning
    Zhiheng WANG, Yanyan XU
    2023, 44(9):  188-204.  doi:10.11959/j.issn.1000-436x.2023162
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    Smartphones are usually provided with indoor positioning services by third-party positioning service providers, in which the unique privacy leakage risk has become a major factor limiting its development.How to protect the privacy of users and data in the positioning process has become an important issue to be solved.The research progress of indoor positioning privacy protection in recent years was reviewed.The commonly used indoor positioning technologies were introduced, different implementation architectures of indoor positioning systems and their threat models, privacy protection requirements were discussed, security technologies applied to indoor positioning privacy protection were summarized, indoor positioning privacy protection schemes for different architectures were classified and introduced, and the performance of different schemes and their advantages and disadvantages were comprehensively compared and analyzed, and finally future research trends were summarized and looked forward to.

    Correspondences
    Keyword-aware optimal route planning method for large-scale graph data
    Ziyang LI, Pengcheng CHEN, Jiong YU, Yonglin PU, Zhenzhen HE, Xue LI, Shijie ZHENG
    2023, 44(9):  205-217.  doi:10.11959/j.issn.1000-436x.2023171
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    Focused on the problem that the planned routes cannot meet the personalized demand of different users in route planning of personalized self-driving tour, a keyword-aware optimal route planning method based on different user interests was proposed.Firstly, the road network information preprocessing model was set up and the road network information query graph was built by the road network information preprocessing algorithm.Secondly, the inverted index algorithm was proposed to prune the road network information query graph according to the personalized requirements from users, which improved the execution efficiency of keyword-aware optimal route planning method and reduced the memory cost of large-scale data processing effectively.Finally, the keyword-aware optimal route planning algorithm was proposed to realize personalized recommendation according to user interest by bidirectional parallel extension.The experimental results show that the method not only realizes the route planning to meet the individual needs of users but also improves the execution efficiency of the method through pruning and bidirectional parallel extension.

    Multi frequency hopping network station sorting based on joint feature clustering in complex environment
    Zhengyu ZHU, Jiazheng WANG, Jing LIANG, Zhongyong WANG, Kexian GONG
    2023, 44(9):  218-227.  doi:10.11959/j.issn.1000-436x.2023164
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    In order to remove interference from hybrid signals and sort each frequency hopping station signal, a multi frequency hopping network station sorting algorithm based on joint feature clustering was proposed.Firstly, short-time Fourier transform was applied to the sorted hybrid signals to obtain the time-frequency matrix, and adaptive threshold denoising was carried out according to the energy distribution histogram of time-frequency matrix.Secondly, the sweep interference was removed by morphological filtering.Thirdly, the connected domain was labeled, the duration and average energy of each signal were calculated to remove the fixed frequency interference, and the joint feature vector for each frequency hop was formed.Finally, the MeanShift algorithm was used to cluster and analyze the joint feature vectors of each segment of the signal, completing the sorting of each frequency hopping signal.The simulation results show that the proposed algorithm has higher sorting rate, stronger anti-interference ability and wider applicability to hybrid signals compared with the traditional algorithm.

    Beamforming and resource optimization in UAV integrated sensing and communication network with edge computing
    Bin LI, Sicong PENG, Zesong FEI
    2023, 44(9):  228-237.  doi:10.11959/j.issn.1000-436x.2023172
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    To address the dependence of traditional integrated sensing and communication network mode on ground infrastructure, the unmanned aerial vehicle (UAV) with edge computing server and radar transceiver was proposed to solve the problems of high-power consumption, signal blocking, and coverage blind spots in complex scenarios.Firstly, under the conditions of satisfying the user’s transmission power, radar estimation information rate and task offloading proportion limit, the system energy consumption was minimized by jointly optimizing UAV radar beamforming, computing resource allocation, task offloading, user transmission power, and UAV flight trajectory.Secondly, the non-convex optimization problem was reformulated as a Markov decision process, and the proximal policy optimization method based deep reinforcement learning was used to achieve the optimal solution.Simulation results show that the proposed algorithm has a faster training speed and can reduce the system energy consumption effectively while satisfying the sensing and computing delay requirements.

Copyright Information
Authorized by: China Association for Science and Technology
Sponsored by: China Institute of Communications
Editor-in-Chief: Zhang Ping
Associate Editor-in-Chief:
Zhang Yanchuan, Ma Jianfeng, Yang Zhen, Shen Lianfeng, Tao Xiaofeng, Liu Hualu
Editorial Director: Wu Nada, Zhao Li
Address: F2, Beiyang Chenguang Building, Shunbatiao No.1 Courtyard, Fengtai District, Beijing, China
Post: 100079
Tel: 010-53933889、53878169、
53859522、010-53878236
Email: xuebao@ptpress.com.cn
Email: txxb@bjxintong.com.cn
ISSN 1000-436X
CN 11-2102/TN
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