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Multi-image encryption combining four-dimensional chaotic systems and multi-layer embedding

The European Physical Journal Special Topics 2024年 1-18页

作者： Zhou, Kai Zhang, Jiaxin Xiang, Jianhong Zhong, Yu College of Information and Communication Engineering Harbin Engineering University Harbin China Key Laboratory of Advanced Ship Communication and Information Technology Harbin Engineering University Harbin China Sichuan Key Laboratory of Agile Intelligent Computing Chengdu China

A multi-image encryption technique combining a four-dimensional chaotic system and multi-layer embedding is proposed because images are easily attacked from the outside during network transmission and that traditional image encryption algorithms have limitations such as long encryption time, low ciphertext image security, and poor information diffusion when a single image is encrypted multiple times. algorithm first creates a four-dimensional chaotic system to produce chaotic sequences; the system’s positive Lyapunov exponent indicates that it has chaotic properties in four directions; then, multiple images are processed using multi-layer embedding and chaotic sequences to create a composite image. Next, block scrambling and variable parameter Arnold’s scrambling are combined to perform block sorting and pixel disorder on the composite image. Lastly, the composite image is processed in separate blocks to execute various encryption techniques. To obtain the ciphertext image, several blocks are finally treated using either same-or-different-or diffusion processing. Simulation experiments show that this algorithm has a faster encryption time, better security and information diffusion in the encrypted image, a maximum correlation value of $$-$$ 0.00244 between adjacent pixels in the ciphertext image, and UACI of 33.4663% and 99.6086%, respectively (the theoretical values are 0, 99.61% and 33.46%)

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Design and Analysis of Inter-RBs Hopping SCMA System under Jamming Attacks 22

Design and Analysis of Inter-RBs Hopping SCMA System under J...

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22nd IEEE International Conference on Communication Technology, ICCT 2022

作者： Yang, Kun Zeng, Qi Liu, Xing Fang, Ke Niu, Xianhua College of Electrical Engineering Sichuan University Chengdu China Agile and Intelligent Computing Key Laboratory of Sichuan Province Chengdu China College of Computer Xihua University Chengdu China

ISBN: (纸本)9781665470674

Sparse code division multiple access (SCMA) technology has superior time-frequency resource utilization, which can support a large-scale connectivity in B5G/6G cellular. However, the prototypical SCMA always transmits the non-zero code-words over the fixed resource-blocks (RBs), thus likely suffering from severe performance degradation due to the external jamming threats. To address this issue, an improved SCMA system based on inter-RBs hopping is proposed in this paper, where physical RBs utilized by codewords are randomly hopped over the RB-group (i.e., frequency-hopped (FH) subcarriers). To implement the optimal inter-RB hopping SCMA, a pseudo-random hopping strategy is designed via prime code and interleavering operations. By such a hopping strategy, the instantaneous RB of SCMA is uniformly operated over the whole RB-group. Followed by the transceiver of proposed inter-RB hopping SCMA, the signal processing is derived in details. The signal processing and simulation results show that, under the jamming scenarios, the proposed inter-RB hopping SCMA system can reduce/average the effect of jamming on bit-error-rate performance, compared to the traditional SCMA systems. © 2022 IEEE.

关键词： Code division multiple access

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A Parallel GMRES Method for Large Linear System

A Parallel GMRES Method for Large Linear System

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Computer Technology and Information Science (ISCTIS), International Symposium on

作者： Kangxin He Guojiang Xi Ying Chen Agile And Intelligent Computing Key Laboratory of Sichuan Province Southwest China Institute of Electronic Technology Chengdu China

Solving large linear system is of fundamental importance in engineering and scientific computing. Based on a multi-core CPU cluster, we propose a parallel GMRES (Generalized Minimal Residual) method to solve a large linear system ${Ax}={b}$ , where $A$ is an ${n}\times {n}$ matrix, and in practice, ${n}$ can be 10 5 or even 10 6 . We validate the effectiveness of the algorithm with the test problem coming from the finite element discretization of Poisson equation.

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Channel estimation for massive MIMO systems based on adaptive angular domain compensation 23

Channel estimation for massive MIMO systems based on adaptiv...

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Proceedings of the 2023 5th International Conference on Video, Signal and Image Processing

作者： Ting Liu Yong Wang Jianhong Xiang Ying Wang Yang Liu College of Information and Communication Engineering Harbin Engineering University China Sichuan Key Laboratory of Agile Intelligent Computing Southwest China Institute of Electronics Technology China

ISBN: (纸本)9798400709272

Millimeter-wave (mmWave) and massive Multiple Input Multiple Output (MIMO) technologies rely heavily on accurate channel state information (CSI) to significantly increase system capacity. However, the large size of the antenna array makes it more difficult to obtain accurate channel state information. We propose to utilize beam domain channels to improve the channel estimation accuracy. Specifically, we first construct the angular domain compensation. By utilizing this angular domain compensation, we further propose an angular domain compensated alternating direction multiplier method (ADC-ADMM) algorithm. The scheme models the channel estimation problem as a bi-objective convex optimization problem with joint angular domain compensation, which can capture channel state information more comprehensively. In addition, the angular domain compensation can provide a priori information and improve the robustness in noisy environments. The simulation results confirm the feasibility of the proposed ADC-ADMM scheme.

关键词： ADC-ADMM Millimeter wave (mmWave) Multiple Input Multiple Output (MIMO) channel estimation

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OTFS Channel Estimator based on Embedded Pilot Sequence Similarity

OTFS Channel Estimator based on Embedded Pilot Sequence Simi...

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Communication Technology and Information Technology (ICCTIT), International Conference on

作者： Youzhi Zhao Linyu Wang Jianhong Xiang Yang Liu College of Information and Communication Engineering Harbin Engineering University Harbin China Agile and Intelligent Computing Key Laboratory China Electronic Technology Group(cetc-10) Sichuan China

ISBN: (数字)9798331528973

ISBN: (纸本)9798331528980

Traditional orthogonal time-frequency space (OTFS) channel estimation schemes place guard symbols around pilots to avoid interference from data symbols, thereby reducing spectrum efficiency (SE). To address this issue, this paper proposes an OTFS channel estimator based on the similarity of embedded pilot sequences (EPSS). Firstly, according to prior channel information, multiple pilots are sparsely embedded into an OTFS data frame, preventing mutual interference between pilots while fully utilizing the channel diversity gain, and the guard symbols of the pilots at the transmitter are revoked to improve SE. Secondly, at the receiver, a shift sequence with strong correlation to the embedded pilot sequence at the transmitter is designed. Through linear search, when the autocorrelation value of the shift sequence with the pilot sequence is greater than a threshold, the delay-Doppler taps of the channel can be estimated. Finally, an inverse gain matrix is designed to eliminate interference from data symbols to the pilots, thereby obtaining the channel gain. Through the design of an OTFS communication system, simulation results verify that the EPSS scheme significantly improves SE with a slight reduction in reliable communication performance.

关键词： Time-frequency analysis Spectral efficiency Partial transmit sequences Simulation Channel estimation Symbols Interference Receivers Diversity methods Autocorrelation

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Near-field Beamforming Technique Based on 3-D Cylindrical Array: Enlarging Region and Improving Spectral Efficiency

Near-field Beamforming Technique Based on 3-D Cylindrical Ar...

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IEEE Asia-Pacific Conference on Antennas and Propagation (APCAP)

作者： Shuai Gao Kai Zhou Ying Wang Jianhong Xiang Yu Zhong College of Information and Communication Engineering Harbin Engineering University Harbin China Agile and Intelligent Computing Key Laboratory China Electronic Technology Group (Cetc-10) Chengdu China

ISBN: (数字)9798350351019

ISBN: (纸本)9798350351026

For large incidence/emergence angles in uniform linear arrays, the near-field region shrinks sharply. In this paper, we present Uniform 3D Cylindrical Array (UCA-3D), which can enlarge the near-field region and improve the spectral efficiency. Specifically, using the rotational symmetry of UCA-3D, we can obtain near-field regions that are uniformly enlarged at all angles. As UCA-3D can generate orthogonal near-field beams along the same direction, we can improve the spectral efficiency. The simulation results prove that the theory is valid, and the UCA-3D is feasible.

关键词： Three-dimensional displays Spectral efficiency Array signal processing Simulation Antenna arrays

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An Encoded Double Auxiliary Pilot Channel Estimation Method for Intrinsic Interference Cancellation in FBMC/OQAM Systems

An Encoded Double Auxiliary Pilot Channel Estimation Method ...

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IEEE International Conference on Artificial Intelligence in Engineering and Technology (IICAIET)

作者： Sixuan Xing Jianhong Xiang Ying Wang Liangang Qi Yu Zhong College of Information and Communication Engineering Harbin Engineering University Harbin China Key Laboratory of Advanced Ship Communication and Information Technology Harbin Engineering University Harbin China Agile and Intelligent Computing Key Laboratory Chengdu China

ISBN: (数字)9798350389692

ISBN: (纸本)9798350389708

Filter bank multicarrier technique (FBMC) is considered as a promising modulation technique suitable for future communications. However, the presence of intrinsic interference prevents the efficient implementation of techniques such as channel estimation. This paper presents a encode double auxiliary pilot channel estimation method (EDAP) for filter bank multicarrier offset quadrature amplitude modulation (FBMC/OQAM) systems. In order to eliminate the intrinsic interference, we add auxiliary symbols around the pilot, and at the same time perform a precoding process to minimize the auxiliary pilot energy loss and computational complexity. In order to validate the above method, the OQAM/FBMC system is modeled. Theoretical analysis and numerical results show that the method improves the channel estimation accuracy by 2.15-3.22 dB in double selective channels while maintaining low power consumption and low complexity.

关键词： Power demand Spectral efficiency Quadrature amplitude modulation System performance Precoding Channel estimation Filter banks Symbols Filtering algorithms Numerical models

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Noise Detection and Removal for Underground Communication Systems Based on L2 N onnal Inner Product

Noise Detection and Removal for Underground Communication Sy...

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IEEE International Conference on Artificial Intelligence in Engineering and Technology (IICAIET)

作者： Bangwei Yu Yong Wang Liangang Qi Yang Liu College of Information and Communication Engineering Harbin Engineering University Harbin China Key Laboratory of Advanced Ship Communication and Information Technology Harbin Engineering University Harbin China Sichuan Key Laboratory of Agile Intelligent Computing Chengdu China

ISBN: (数字)9798350389692

ISBN: (纸本)9798350389708

In underground communication systems, continuous mud pulse signals are susceptible to pump noise during transmission, resulting in a high bit error rate(BER). In this paper, a Normal Inner Product Orthogonal Matching Pursuit(NIPOMP) algorithm is proposed for the transmission characteristics of continuous waves in the underground. First, a cyclic prefix(CP) is added in front of the sent data. Then the observation vector is obtained by making a difference between the CP of the latter set of data and the CP of the former set of data. Then, the columns of the sensing matrix that are most correlated with the observation vectors are selected as candidate support sets by calculating the L2 norm. The least squares method was used to solve for the previous set of pump noise estimates. Finally, the pump noise is reconstructed using the correspondence between the time and frequency domains. This paper establishes a complete underground communication system. We discuss the noise characteristics of pump noise and analyze the denoising performance of the NIPOMP algorithm in depth. Simulation results show that the algorithm significantly reduces the system BER in complex channel environments with more drastic fading, including gas-phase, liquid-phase, gas-liquid two-phase, and liquid-solid two-channel environments.

关键词： Liquids Communication systems Simulation Oils Noise Noise reduction Matching pursuit algorithms Vectors Sensors Signal to noise ratio

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DOA estimation for beam scanning radar based on sparse signal reconstruction with incomplete pulse

DOA estimation for beam scanning radar based on sparse signa...

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2022 IEEE International Conference on Signal Processing, Communications and computing, ICSPCC 2022

作者： Wu, Ran Zhang, Yan Ni, Lihua Zhang, Kehao Liu, Ning Wan, Qun University of Electronic Science and Technology of China School of Information and Communication Engineering Chengdu611731 China Northern Institute of Electronic Equipment Beijing100191 China Agile and Intelligent Computing Key Laboratory of Sichuan Province Chengdu611731 China

ISBN: (数字)9781665469722

ISBN: (纸本)9781665469722

Direction of Arrival (DOA) is one of the commonly used measurement for source localization. However, the receiving equipment of modern electronic reconnaissance can not completely intercept the pulse signal in the complex and dense electromagnetic environment. Thus, it is not easy to accurately estimate its DOA, especially in the case of multiple targets. In order to solve this problem, we propose a sparse super-resolution DOA method to achieve DOA estimation incomplete pulse. Combined with compressed sensing theory, the complex DOA estimation problem is transformed into Basis Pursuit (BP) method based on the minimum 1 norm optimization criterion. The method estimates the DOA by solving the optimal sparse vector that constitutes the signal and can detect multiple targets in the same range-azimuth unit. In addition, compared with the traditional direction-finding method using the BP method, our method can guarantee the performance of direction-finding while reducing the requirement of pulse integrity. The simulation results support the theoretical analysis. © 2022 IEEE.

关键词： Direction of arrival

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K-Means Clustering based Sparse Cross-Entropy Minimization algorithm for DOA estimation

K-Means Clustering based Sparse Cross-Entropy Minimization a...

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IET International Radar Conference (IRC 2023)

作者： Qiang Guo Hanyu Jiang Jianhong Xiang Yu Zhong College of Information and Communication Harbin Engineering University Harbin People's Republic of China Agile and Intelligent Computing Key Laboratory Chengdu People's Republic of China

ISBN: (数字)9781837240982

Aiming at the problem that traditional greedy class compressed sensing algorithms are influenced by noise in the estimation of direction of arrival (DOA), this paper proposes the K-Means Clustering based Sparse Cross-Entropy Minimization (KMCSCEM) algorithm. First the algorithm selects atoms by minimizing the sparse cross-entropy to improve the accuracy of atom selection at the low signal-to-noise ratio (SNR). Subsequently, K-mean clustering is added in each iteration to reduce the range of atom selection, which further improves the estimation accuracy. Finally, the speed of convergence is improved by introducing an orthogonal least squares (OLS) criterion. Simulation experiments show that the proposed algorithm has an exact estimation ratio close to 90% when the SNR is less than -5 dB.

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