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IEEE International Conference on Electronic Information and Communication Technology (ICEICT)

作者： Ting Zeng Li Deng Shufang Li Botao Feng Beijing Laboratory of Advanced Information Networks & Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China College of Electronics and Information Engineering Shenzhen University Shenzhen China

ISBN: (数字)9781728190457

ISBN: (纸本)9781728190464

A reflection metasurface that can generate non-diffraction Bessel beams and achieve anomalous reflection with high efficiency at 5.8 GHz is proposed in this paper. The unit it utilizes has excellent amplitude and phase characteristics, greatly facilitating the construction of the proposed metasurface and laying a solid foundation for the improvement of efficiency. According to non-diffraction theory and anomalous reflection law, two metasurfaces are designed for comparison. The simulation results show that the designed metasurfaces successfully realize the non-diffractive beam with a focusing distance of 126 mm (2.44 λ 0 ), and can bend the normally reflected wave to the direction 10° from the +z direction in a vertical plane 45° away from the +x direction. The average efficiency of the metasurface within the focusing range is as high as 84.5%, thus could be used as radio energy transmission, telecommunication multiplexing and accurate detection devices.

关键词： Multiplexing system dynamics Focusing Metasurfaces Solids Reflection Structural beams

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Reflective Metasurface for Controlling the Beam Divergence Angles of Dual-mode OAM Waves

Reflective Metasurface for Controlling the Beam Divergence A...

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IEEE International Conference on Electronic Information and Communication Technology (ICEICT)

作者： Xiaoyuan He Li Deng Botao Feng Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture Convergence Beijing University of Posts and Telecommunications Beijing China College of Electronics and Information Engineering Shenzhen University Shenzhen China

ISBN: (数字)9781728190457

ISBN: (纸本)9781728190464

For dealing with the problem of receiving multimode orbital-angular momentum (OAM) waves resulting from different beam divergence angles of OAM waves with different topological charges, it is essential to control the beam divergence angles of OAM waves. In this paper, a method is proposed to control the beam divergence angles of multi-mode OAM waves without modifying the inherent topological charges by a reflective metasurface. Based on this method, a reflective metasurface is properly designed to generate dual-mode OAM waves with equal beam divergence angle. As a dual-mode OAM waves generator, the reflective metasurface is composed of 31x31 metal-insulator-metal elements which is capable to manipulate dual-polarized electromagnetic waves (EMWs) independently. Furthermore, as a beam divergence controller, the reflective metasurface is properly divided into two regions that are responsible for +1 mode and +3 mode OAM waves generations. In this way, dual-mode OAM waves with equal beam divergence angle can be generated by the proposed reflective metasurface. The proposed design provides an efficient technology to control the beam divergence angles of multi-mode OAM waves flexibly, which is conductive to simplify the receiving device in OAM based communication systems.

关键词： Communication systems Conferences Electromagnetic scattering Metasurfaces Orbits Generators Information and communication technology

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Fast Recovery of Low-Rank and Joint-Sparse Signals in Wireless Body Area networks

Fast Recovery of Low-Rank and Joint-Sparse Signals in Wirele...

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IEEE International Conference on Communications in China (ICCC)

作者： Yanbin Zhang Longting Huang Yangqing Li Kai Zhang Changchuan Yin Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China School of Information Engineering Wuhan University of Technology Wuhan China

ISBN: (数字)9781728173276

ISBN: (纸本)9781728173283

E-health monitoring signals collected from wireless body area networks (WBANs) usually have some highly correlated structures in a certain transform domain (e.g., discrete cosine transform (DCT)). We exploit these structures and propose a fast recovery algorithm for low-rank and joint-sparse (L&S) structured WBAN signal in the framework of compressed sensing (CS). By using a simultaneously L&S signal model, we employ the number of the bigger singular values and Bayesian learning which incorporates an L&S-inducing prior over the signal and the appropriate hyperpriors over all hyperparameters to recover the signal. Experiments show that the proposed algorithm has a superior performance to state-of-the-art algorithms.

关键词： Wireless communication Wireless sensor networks Transforms Body area networks Brain modeling Bayes methods Discrete cosine transforms

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A Conformal OAM Metasurface Antenna Based On Holographic Principle

A Conformal OAM Metasurface Antenna Based On Holographic Pri...

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Asia-Pacific Conference on Microwave

作者： Xiaokui Ren Li Deng Chen Zhang Botao Feng Beijing Laboratory of Advanced Information Networks & Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunication Beijing China College of Electronics and Information Engineering Shenzhen University Shenzhen China

ISBN: (数字)9781728169620

ISBN: (纸本)9781728169637

We present a conformal metasurface antenna implemented by the holographic method that can be wrapped on the cylindrical carrier and produce the OAM spiral wave-front. Then the radiant principle of a holographic antenna is introduced. Through the derivation, we obtain the formula of three-dimensional phase distribution on this conformal metasurface, and the simulation results are consistent with expected effects.

关键词： Spirals Surface waves Simulation Metasurfaces Microwave theory and techniques Electric fields Antennas

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Hypergraph-Coloring-Based Pilot Allocation Algorithm for Massive MIMO systems

Hypergraph-Coloring-Based Pilot Allocation Algorithm for Mas...

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International Conference on Communications, Signal Processing, and systems, CSPS 2018

作者： Lian, Yongjin Zhang, Tiankui Wang, Youxiang Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing100876 China China Unicom Network Technology Research Institution Beijing China

ISBN: (纸本)9789811362637

Pilot contamination caused by unavoidable reuse of pilots in adjacent cell limits the performance of the massive multiple-input multiple-output (MIMO) systems severely. In this paper, we propose a hypergraph-coloring-based pilot allocation (HCPA) algorithm for pilot contamination mitigation, which can improve the system sum rate with the minimum achievable data rate requirement. In the proposed algorithm, an interference relationship graph with hyperedges to restrict the minimum uplink achievable rate is established, and then the pilots are allocated by graph coloring method. The numerical results show that the proposed algorithm can improve both the minimum achievable data rate and the total uplink sum rate. © 2019, Springer Nature Singapore Pte Ltd.

关键词： MIMO systems

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Adaptive Information Bottleneck Guided Joint Source and Channel Coding for Image Transmission

arXiv

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arXiv 2022年

作者： Sun, Lunan Yang, Yang Chen, Mingzhe Guo, Caili Saad, Walid Poor, H. Vincent The Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing100876 China The Department of Electrical and Computer Engineering Institute for Data Science and Computing University of Miami Coral GablesFL33146 United States The Beijing Laboratory of Advanced Information Net works School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing100876 China The Wireless@VT Group Bradley Department of Electrical and Computer Engineering Virginia Tech ArlingtonVA United States The Department of Electrical and Computer Engineering Princeton University PrincetonNJ08544 United States

Joint source and channel coding (JSCC) for image transmission has attracted increasing attention due to its robustness and high efficiency. However, the existing deep JSCC research mainly focuses on minimizing the distortion between the transmitted and received information under a fixed number of available channels. Therefore, the transmitted rate may be far more than its required minimum value. In this paper, an adaptive information bottleneck (IB) guided joint source and channel coding (AIB-JSCC) method is proposed for image transmission. The goal of AIB-JSCC is to reduce the transmission rate while improving the image reconstruction quality. In particular, a new IB objective for image transmission is proposed so as to minimize the distortion and the transmission rate. A mathematically tractable lower bound on the proposed objective is derived, and then, adopted as the loss function of AIB-JSCC. To trade off compression and reconstruction quality, an adaptive algorithm is proposed to adjust the hyperparameter of the proposed loss function dynamically according to the distortion during the training. Experimental results show that AIB-JSCC can significantly reduce the required amount of transmitted data and improve the reconstruction quality and downstream task accuracy. Copyright © 2022, The Authors. All rights reserved.

关键词： Economic and social effects

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Low Complexity Joint User Scheduling and Hybrid Beamforming for mmWave Massive MIMO systems

Low Complexity Joint User Scheduling and Hybrid Beamforming ...

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IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC)

作者： Xiaomeng Gao Xiaoyong Wu Zhilong Zhang Danpu Liu Beijing University of Posts and Telecommunications Beijing P. R. China Shanghai Radio Equipment Research Institute P.R. China Beijing Laboratory of Advanced Information Network Beijing Key Laboratory of Network System Architecture and Convergence

ISBN: (数字)9781728144900

ISBN: (纸本)9781728144917

Codebook-based hybrid analog and digital beam-forming (HBF) plays a key role in practical millimeter wave (mmWave) massive MIMO systems. Most existing work focuses on the design of analog beams, without considering the coupled relationship between beam selection and user scheduling. In this paper, we consider a downlink HBF system and address the aforementioned problem. By exploiting the orthogonality of the Discrete Fourier Transform (DFT) codebook, we propose two low complexity approaches named as E-DFT and PF-DFT according to different requirements. Specifically, E-DFT aims to maximize the sum achievable rate of the HBF system, and PF-DFT considers both the system throughput and user fairness. Simulation results show that our proposed E-DFT scheme outperforms the baseline methods in the literature, and achieves near optimal sum rate. Meanwhile, the PF-DFT scheme performs better in balancing the achievable rate and scheduling fairness.

关键词： Radio frequency Array signal processing NIST MIMO communication Complexity theory Discrete Fourier transforms Baseband

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A novel received signal strength assisted perspective-three-point algorithm for indoor visible light positioning

arXiv

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arXiv 2020年

作者： Bai, Lin Yang, Yang Feng, Chunyan Guo, Caili Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing Laboratory of Advanced Information Networks School of Information and Communication Engineering Beijing University of Posts and Telecommunications

In this paper, a received signal strength assisted Perspective-three-Point positioning algorithm (R-P3P) is proposed for visible light positioning (VLP) systems. The basic idea of R-P3P is to joint visual and strength information to estimate the receiver position using 3 LEDs regardless of the LEDs' orientations. R-P3P first utilizes visual information captured by the camera to estimate the incidence angles of visible lights. Then, R-P3P calculates the candidate distances between the LEDs and the receiver based on the law of cosines and Wu-Ritt's zero decomposition method. Based on the incidence angles, the candidate distances and the physical characteristics of the LEDs, R-P3P can select the exact distances from all the candidate distances. Finally, the linear least square (LLS) method is employed to estimate the position of the receiver. Due to the combination of visual and strength information of visible light signals, R-P3P can achieve high accuracy using 3 LEDs regardless of the LEDs' orientations. Simulation results show that R-P3P can achieve positioning accuracy within 10 cm over 70% indoor area with low complexity regardless of LEDs orientations. Copyright © 2020, The Authors. All rights reserved.

关键词： Light emitting diodes

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Dynamic Frame-Slotted Aloha in RFID Using Received Signal Strength Information

Dynamic Frame-Slotted Aloha in RFID Using Received Signal St...

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Canadian Conference on Electrical and Computer Engineering (CCECE)

作者： Gan Luan Norman C. Beaulieu School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing China School of Information and Communication Engineering and the Beijing Key Laboratory for Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

ISBN: (数字)9781728154428

ISBN: (纸本)9781728154435

Received signal strength information based dynamic frame-slotted Aloha (RSSI-DFSA) RFID is proposed to replace random slot access where idle and collided slots lead to low system efficiency. Tag coordinates are calculated from received signal strength information, and the slot is chosen based on the coordinates. Simulations show that RSSI-DFSA system efficiencies are 14.9%, 2.4%, and 2.1% higher, and the time efficiencies are 8.3%, 2.5%, and 1.8% higher than those of existing algorithms, when the path loss exponent is 4 and the standard deviations of the shadowing are 1, 2, and 3 dB.

关键词： Heuristic algorithms Standards Passive RFID tags Estimation Shadow mapping Conferences Probabilistic logic

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A Simple Novel Idle Slot Prediction and Avoidance Scheme Using Prediction Bits for DFSA in RFID

A Simple Novel Idle Slot Prediction and Avoidance Scheme Usi...

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IEEE Conference on Wireless Communications and networking

ISBN: (数字)9781728131061

ISBN: (纸本)9781728131078

Idle slots cause identification inefficiency in Aloha-based RFID algorithms. An idle slot prediction and elimination technique is proposed. The algorithm is dubbed idle predicting dynamic frame-slotted Aloha (IP-DFSA). In IP-DFSA, the reader reads a slot for RN16 as well as the idle prediction bits. Using only a few prediction bits, IP-DFSA can predict and eliminate a significant number of successive idle slots following the current time slot. Whereas previous schemes only achieve 36% efficiency on average, simulation results show that IP-DFSA with 1, 2, 3, and 4 idle slot prediction bits achieves 45%, 52.5%, 56%, and 60% system efficiencies, with 83%, 86%, 88%, and 89% time efficiencies, respectively. The system efficiencies of IP-DFSA range from 9% higher to 24% higher than previous schemes for 1 prediction bit to 4 prediction bits. The number k of idle prediction bits is optimized, and it is revealed that k optimal =4 for tag numbers n≥6.

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