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International Conference on Communication Technology (ICCT)

作者： Dingcheng Zhu Yijing Yao Lei Xu Hongwei Zhang Hongyu Fang Xiaohui Li Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education Anhui University Hefei china

The closed-form formula derivation of the power domain cooperative Non-Orthogonal Multiple Access (NOMA) system is of great significance for further improving the performance of the system. However, the system performance formulas of the channel capacity and the paired bit error rate Pairwise Error Probability (PEP) are too complicated, which have increased the difficulty in system performance optimization. Therefore, based on the Amplify Forward (AF) relay cooperative NOMA model, the signal Interference Noise Ratio (SINR) formulas of the two weak-user nodes are constructed. Through the assumption of that, the Symbol Error Rate (SER) of each user is fair, the simplification condition of Moment Generating Function (MGF) with the harmonic mean form is satisfied. Combined with the SER calculation formula of MGF, the system SER asymptotically tight approximation formula with simple structure is derived at high signal-to-noise ratio (SNR). The Monte Carlo simulation results show that, the formula can accurately describe the SER performance of the power domain cooperative NOMA system with the non-ideal Successive Interference Cancellation (SIC) system when SNR is high. Under the condition of certain total power, the optimal power distribution factor is solved in order to minimize the total system SER.

关键词： Conferences Communications technology

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Dynamic Multi-user Detection Scheme Based on CVA-SSAOMP Algorithm in Uplink Grant-Free NOMA

Dynamic Multi-user Detection Scheme Based on CVA-SSAOMP Algo...

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International Conference on Communication Technology (ICCT)

作者： Jian Zhang Shichao Bai Lei Xu Hongwei Zhang Hongyu Fang Xiaohui Li Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education Anhui University Hefei China

In the uplink grant-free non-orthogonal multiple access (NOMA) scenario, since the active user at the sender has a structured sparsity transmission characteristic, the compressive sensing recovery algorithm is initially applied to the joint detection of the active user and the transmitted data. However, the existing compressive sensing recovery algorithms with unknown sparsity often require noise power or signal-to-noise ratio (SNR) as the priori conditions, which greatly reduces the algorithm adaptability in multi-user detection. Therefore, an algorithm based on cross validation aided structured sparsity adaptive orthogonal matching pursuit (CVA-SSAOMP) is proposed to realize multi-user detection in dynamic change communication scenario of channel state information (CSI). The proposed algorithm transforms the structured sparsity model into a block sparse model, and without the priori conditions above, the cross validation method in the field of statistics and machine learning is used to adaptively estimate the sparsity of active user through the residual update of cross validation. The simulation results show that, compared with the traditional orthogonal matching pursuit (OMP) algorithm, subspace pursuit (SP) algorithm and cross validation aided block sparsity adaptive subspace pursuit (CVA-BSASP) algorithm, the proposed algorithm can effectively improve the accurate estimation of the sparsity of active user and the performance of system bit error ratio (BER), and has the advantage of low-complexity.

关键词： Matching pursuit algorithms Heuristic algorithms signal processing algorithms Multiuser detection Machine learning algorithms Adaptation models Periodic structures

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Electromagnetic Compatibitility Analysis with Ultra-Wideband Simultaneous Switching Noise Suppression for Antenna-in-Package

Electromagnetic Compatibitility Analysis with Ultra-Wideband...

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Hao-Ran Zhu Yu-Fa Sun Xian-Liang Wu Ministry of Education Key Laboratory of Intelligent Computing and Signal Processing Anhui University Hefei China

ISBN: (数字)9780996007894

ISBN: (纸本)9781728146331

In this paper, a compact power distribution network (PDN) structure with ultra-wideband simultaneous switching noise (SSN) mitigation for antenna in package is presented. Only one spiral slot is etched on the square patch of the EBG pattern, which is constituted the presented PDN structure. The equivalent circuit model is developed to analyze the mechanism of the electromagnetic compatibility behavior that a high-impedance is provided for reducing the SSN coupling. An ultra-wideband SSN mitigation performance is obtained from 0.35 GHz to 20 GHz under the suppression level of -40 dB. Good agreements are observed between the simulated and measured results.

关键词： Periodic structures Metamaterials Spirals Switches Equivalent circuits Integrated circuit modeling Power systems

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A Compact Circularly Polarized Mono-pulse Antenna with Frequency Agility

A Compact Circularly Polarized Mono-pulse Antenna with Frequ...

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Progress in Electromagnetics Research Symposium - Fall (PIERS - FALL)

作者： Yan Xue Jie Wu Lihua Wang Key Laboratory of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei China

ISBN: (数字)9781728153049

ISBN: (纸本)9781728153056

This paper presents a 1 × 4 circularly polarized patch antenna array with frequency agility. A compact 4-cell array patch antenna with low-profile (i.e., about 0.013λ 0 ) has been designed for circular polarization mono-pulse applications. By properly switching between the different states of these p-i-n diodes, four discrete operating frequency bands can be achieved. Circularly polarization can be achieved by the perturbation segment. A Rat-Race coupler based feed network is developed showing the high isolation between input terminals as well as efficient placement of sum and difference ports, including to generate sum and difference patterns for mono-pulse applications operating. Because of a suitable replacement of the sum and difference ports, the antenna radiation patterns were symmetrical. The simulated peak gains of the four discrete operating frequencies for 4.4 GHz, 4.7 GHz, 5.3 GHz and 5.6 GHz are 11.7 dBi, 12.0 dBi, 12.1 dBi, and 12.3 dBi, respectively. Both the null-depth at four different frequencies are less than -15 dBi. The simulation results show that the 3 dB axial ratio at four different center frequencies are 0.89 dB, 1.87 dB, 0.91 dB and 2.15 dB, respectively.

关键词： Antenna arrays Switches Patch antennas Pins Polarization Antenna radiation patterns

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A Compact Bandpass Filter Using Novel Microstrip Dual-mode Resonator with Hexagonal Structure

A Compact Bandpass Filter Using Novel Microstrip Dual-mode R...

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Progress in Electromagnetics Research Symposium - Fall (PIERS - FALL)

作者： Xin-Yu Ning Han-Ran Zhu Zhi-Xiang Huang Key Laboratory of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei China

ISBN: (数字)9781728153049

ISBN: (纸本)9781728153056

A dual-mode bandpass filter with miniaturized size is presented in this paper. A hexagonal microstrip dual-mode resonator is employed to reduce the size of the filter. A pair of tortuous parallel coupled input and output structures are used to introduce the transmission zeros, which can improve the selectivity and the stopband of the filter. Compared to other dual-mode resonator filters, a compact advantage is also achieved with the presented design. A sample circuit is fabricated with the thin film technology to validate the design. The size of the filter is 4.98 × 4.57mm 2 , which is equivalent to $0.147 \times 0.134\lambda _g^2$ at 8.75GHz. The prototype filter has a fractional bandwidth of 5.7%, a low passband insertion loss of 0.6dB. Moreover, excellent out-of-band rejection characteristics are achieved in the hexagonal dual mode filter. Four transmission zeros are generated in the stopband to improve out-of-band rejection, and out of-band rejection greater than 20dB can be achieved in the stopband below 15GHz. In addition, a size reduction of approximately 30% is observed when compared with miniaturized rectangular ring patch resonators, for the same center frequency.

关键词： Microstrip resonators Resonant frequency Optical ring resonators Filtering theory Passband Perturbation methods

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Cancelable Finger Vein Template Based on Variable Curvature Gabor Gilter and Improved Canonical Correlation Analysis

Cancelable Finger Vein Template Based on Variable Curvature ...

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IEEE International Conference on Information Communication and signal processing (ICICSP)

作者： Lulu Ye Huabin Wang Yufeng Shi Liang Tao Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education Anhui University Hefei China

At present, the biometric template algorithms with state of the art recognition performance cannot guarantee the security of the system, whereas the security biometric template algorithms usually suffer from inaccurate recognition. In order to improve both the recognition performance and security of feature template for finger vein, a cancelable template algorithm is proposed in this paper. Firstly, a variable curvature Gabor filter is designed for finger vein orientation feature extraction. The maximum and sub-maximum orientation of Gabor filter are combined with differential excitation respectively to generate joint distribution features, which serve as feature vectors of finger vein. Secondly, the extracted feature vectors are reduced dimension by PCA, and the reduced feature vectors are combined with the pseudo random matrix, which is produced by a token to generate a cancelable template to guarantee the security. Finally, cancelable templates in two orientations are fused to increase the irreversibility of templates by using the improved canonical correlation analysis. Extensive experiments on the SDUMLA-FV and PolyU databases demonstrate the superiority of the proposed method in terms of verification performance, diversity, revocability/reusability and irreversibility.

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A Low-Complexity and High-Efficient Pilot Allocation Scheme Based on User Grouping in Massive MIMO System

A Low-Complexity and High-Efficient Pilot Allocation Scheme ...

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International Conference on Communication Technology (ICCT)

作者： Xinying Zhao Yijing Yao Lei Xu Hongyu Fang Hongwei Zhang Xiaohui Li Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education Anhui University Hefei China

Pilot allocation is one of the effective means to reduce pilot pollution in massive Multiple-Input Multiple-Output (MIMO) systems. The goal of this paper is to improve the uplink achievable sum rates of strong users, and ensure the quality of service (QoS) requirements of weak users at the same time, so that the sum rates of system can be improved. Combining with the technical advantage of pilot grouping, a low complexity pilot allocation scheme based on matching algorithm is proposed, which divides the users in the target cell into weak user group and strong user group, and adopts the minimum-maximum matching method to allocate pilots in weak user group. Through the introduction of Hungarian algorithm, a pilot allocation method is designed to ensure the fairness of the strong users. The simulation results show that, compared with the smart pilot allocation scheme, the pilot allocation scheme based on Hungarian algorithm, the pilot allocation scheme based on user grouping and the random pilot allocation scheme, the system performance of the proposed scheme has been effectively improved.

关键词： Resource management Pollution Uplink Interference Fading channels Antennas Massive MIMO

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Separable reversible data hiding based on MSB prediction for encrypted 3D mesh models?

arXiv

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arXiv 2019年

作者： Xu, Na Yin, Zhaoxia Key Lab of Intelligent Computing and Signal Processing of Ministry of Education School of Computer Science and Technology Anhui University Hefei

Reversible data hiding in encrypted domain (RDH-ED) has received tremendous attention from the research community because data can be embedded into cover media without exposing it to the third party data hider and the cover media can be losslessly recovered after the extraction of the embedded data. Although, in recent years, exten- sive studies have been carried out about images based RDH-ED, little attention is paid to RDH-ED in 3D mesh models due to its complex data structure and irregular geometry. We propose a separable RDH-ED method for 3D mesh models based on MSB (most significant bit) predic- tion. Firstly, we divide all the vertices of the mesh into the "embedded" set and "reference" set according to topological information between ver- tices, and calculate the MSB prediction errors for the vertices of the "em- bedded" set. Then, bit-stream encryption is used to encrypt the mesh. Finally, data is embedded by replacing the MSB of the encrypted vertex coordinates of the "embedded" set by the additional data bits. Recipient with data hiding key can correctly extract the additional data from the marked encrypted mesh. Recipient with encryption key can recover the mesh perfectly by using MSB prediction. Experimental results show that the proposed method has higher embedding capacity and higher quality of the recovered meshes compared to the existing RDH-ED method for 3D meshes based on symmetric encryption. Copyright © 2019, The Authors. All rights reserved.

关键词： Forecasting

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Semantic knowledge transfer for semi-supervised medical image segmentation

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Engineering Applications of Artificial Intelligence 2025年 158卷

作者： Shiwei Zhou Haifeng Zhao Leilei Ma Dengdi Sun Key Laboratory of Intelligent Computing & Signal Processing (ICSP) Ministry of Education Anhui University Hefei 230601 China Anhui Provincial Key Laboratory of Multimodal Cognitive Computation Anhui University Hefei 230601 China School of Computer Science and Technology Anhui University Hefei 230601 China School of Artificial Intelligence Anhui University Hefei 230601 China Institute of Artificial Intelligence Hefei Comprehensive National Science Center Hefei 230026 China

In semi-supervised medical image segmentation, due to possible differences in information content and distribution between labeled and unlabeled data, dealing with the two separately usually prevents knowledge transfer from labeled to unlabeled data. This prevents the model from effectively sharing learned information between the two types of data. To alleviate this problem, we train labeled and unlabeled data as a whole. Semantic mixing of labeled and unlabeled data is achieved by selecting and exchanging some of the region images of both through a mask to generate complementary input views. In addition, due to the limited labeled data, the unlabeled data has a weak ability to distinguish categories in the feature space. Traditional methods rely on pixel positions to generate positive and negative samples for contrastive learning to solve this problem, but relying on pixel position sampling can easily lead to semantic inconsistency, which affects the effect of feature learning; therefore, to address this problem, we propose an innovative labeled data-guided inter-class contrastive learning strategy, which extracts the category features from labeled and unlabeled data and exploits the accurate category information in the labeled data to guide contrastive learning, while introducing a similarity-based ranking weighting mechanism. Combining the two designs, we propose a new semantic knowledge transfer framework for semi-supervised medical image segmentation. Experiments demonstrate a significant improvement in our model compared to State of the Art (SOTA) on the Automatic Cardiac Diagnosis Challenge (ACDC) dataset and the Left Atrium (LA) dataset.

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A Wideband Dual-Band Magneto-Electric Dipole Antenna with Modified Feed Structure 10

A Wideband Dual-Band Magneto-Electric Dipole Antenna with Mo...

引用

10th International Conference on Microwave and Millimeter Wave Technology, ICMMT 2018

作者： Li, Fan Sun, Yufa Zhu, Haoran Fang, Ionzvu Anhui University Ministry of Education Key Lab of Intelligent Computing and Signal Processing Hefei230601 China

ISBN: (纸本)9781538624166

In this paper, a novel wideband dual-band magneto-electric dipole antenna with modified feed structure is proposed. Double-layer patches are utilized to design a pair of folding metal. The double-layer patches dipole can generate two resonant frequencies, which are employed to form a dual-band magneto-electric dipole antenna. A stair-shaped feeding strip with a hexagonal structure is designed to modify the impedance matching. It is found from simulated results that two operation bands with bandwidths of 60% from 1.61 to 2.99 GHz and 31.9% from 4.99 to 6.89 GHz under the return loss level of 10 dB were achieved. The gain of the antenna ranged from 7.56 to 10.56 dBi. Furthermore, low cross-polarization level and low back-radiation are also obtained with the proposed antenna. © 2018 IEEE.

关键词： Natural frequencies

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