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Modeling of All-Optical Even and Odd Parity Generator Circuits Using Metal-Insulator-Metal Plasmonic Waveguides

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Photonic Sensors 2017年第2期7卷 182-192页

作者： Lokendra SINGH Amna BEDI Santosh KUMAR Photonics lab Department of Electronics and Communication Engineering DIT University Dehradun-248009 India

Plasmonic metal-insulator-metal （MIM） waveguides sustain excellent property of confining the surface plasmons up to a deep subwavelength scale. In this paper, linear and S-shaped MIM waveguides are cascaded together to design the model of Mach-Zehnder interferometer （MZI）. Nonlinear material has been used for switching of light across its output ports. The structures of even and odd parity generators are projected by cascading the MZIs. Parity generator and checker circuit are used for error correction and detection in an optical communication system. Study and analysis of proposed designs are carried out by using the MATlab simulation and finite-difference- time-domain （FDTD） method.

关键词： Plasmonics MIM waveguides Mach-Zehnder interferometer nonlinear process FDTD method

OvBNN authentication based on cooperative signature for wireless sensor networks

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High Technology Letters 2018年第3期24卷 287-295页

作者：秦丹阳 Zhang Yan Ma Jingya Ji Ping Key lab of Electronic and communication Engineering Heilongjiang University

The universality of the application of wireless sensor networks( WSN) makes more attention be paid on the security problem. Node authentication is not only the basis of network security,but also the premise of key management and secure routing protocol. Although the signature mechanism based on symmetric encryption is high in energy efficiency,it is vulnerable to be attacked and there is a time delay during authentication. Traditional public key encryption mechanism with improvement in security brings in complex algorithm and costs much time,which is not suitable for WSN. In this paper,a signature authentication mechanism,an optimized variant Bellare Namprempre Neven( OvBNN) is presented to quickly complete the authentication by mutual cooperation between nodes so as to make the nodes use the intermediate calculation results of their neighbor nodes *** results show that the proposed mechanism is superior to traditional authentication mechanisms both in energy consumption and authentication time.

关键词： optimized variant Bellare Namprempre Neven (OvBNN) digital signature authentication speed energy consumption wireless sensor networks (WSN)

High speed optical transmission utilizing constant envelope modulation based on frequency shift keying and minimum-shift keying

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Chinese Optics Letters 2010年第9期8卷 837-843页

作者：迟楠方武良邵宇丰张俊文黄博朱江波陶理 Department of communication Science and Engineering State Key Lab of ASIC and System Fudan University

A novel 40-Gb/s constant envelope optical frequency shift keying （FSK） transmitter and the transmission characteristics are investigated both by simulation and experiment. Meanwhile, to increase the spectrum efficiency of FSK, we propose a novel optical minimum-shift keying （MSK） scheme and analyze its per-formance compared with other MSK schemes and other traditional modulation formats. Simulation and experimental results show that the novel FSK scheme could be a potential candidate for the future high speed transmission and label switching systems. And the novel MSK scheme deserves future deep research for its potential excellent performance.

关键词： Light transmission

A digital twins enabled underwater intelligent internet vehicle path planning system via reinforcement learning and edge computing

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digital communications and Networks 2024年第2期10卷 282-291页

作者： Jiachen Yang Meng Xi Jiabao Wen Yang Li Houbing Herbert Song School of Electrical and Information Engineering Tianjin UniversityTianjin300072China Security and Optimization for Networked Globe laboratory(SONG lab) Embry-Riddle Aeronautical UniversityDaytona BeachFL32114USA

The Autonomous Underwater Glider(AUG)is a kind of prevailing underwater intelligent internet vehicle and occupies a dominant position in industrial applications,in which path planning is an essential *** to the complexity and variability of the ocean,accurate environment modeling and flexible path planning algorithms are pivotal *** traditional models mainly utilize mathematical functions,which are not complete and *** existing path planning algorithms depend on the environment and lack *** overcome these challenges,we propose a path planning system for underwater intelligent internet *** applies digital twins and sensor data to map the real ocean environment to a virtual digital space,which provides a comprehensive and reliable environment for path *** design a value-based reinforcement learning path planning algorithm and explore the optimal network structure *** path simulation is controlled by a closed-loop model integrated into the terminal vehicle through edge *** integration of state input enriches the learning of neural networks and helps to improve generalization and *** task-related reward function promotes the rapid convergence of the *** experimental results prove that our reinforcement learning based path planning algorithm has great flexibility and can effectively adapt to a variety of different ocean conditions.

关键词： digital twins Reinforcement learning Edge computing Underwater intelligent internet vehicle Path planning

Efficient stochastic successive cancellation list decoder for polar codes

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Science China(Information Sciences) 2020年第10期63卷 133-151页

作者： Xiao LIANG Huizheng WANG Yifei SHEN Zaichen ZHANG Xiaohu YOU Chuan ZHANG laboratory of Efficient Architectures for digital-communication and Signal-processing (LEADS) Southeast University National Mobile communications Research laboratory Southeast University Quantum Information Center of Southeast University

Polar codes are one of the most favorable capacity-achieving codes owing to their simple structures and low decoding complexity. Successive cancellation list(SCL) decoders with large list sizes achieve performances very close to those of maximum-likelihood(ML) decoders. However, hardware cost is a severe problem because an SCL decoder with list size L consists of L copies of a successive cancellation(SC)decoder. To address this issue, a stochastic SCL(SSCL) polar decoder is proposed. Although stochastic computing can achieve a good hardware reduction compared with the deterministic one, its straightforward application to an SCL decoder is not well-suited owing to the precision loss and severe latency. Therefore,a doubling probability approach and adaptive distributed sorting(DS) are introduced. A corresponding hardware architecture is also developed. Field programmable gate array(FPGA) results demonstrate that the proposed stochastic SCL polar decoder can achieve a good performance and complexity tradeoff.

关键词： SCL polar decoder stochastic computing 2-bit decoding distributed sorting hardware

A Novel Orthogonal LoRa Multiple Access Algorithm for Satellite Internet of Things

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China communications 2022年第3期19卷 279-289页

作者： Chengwen Zhang Liankai Wang Libin Jiao Shipeng Wang Jun Shi Jia Yue School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150080China Science and Technology on communication Networks laboratory Shijiazhuang 050081China Key laboratory of Police Wireless digital communication Ministry of Public SecurityHarbin 150001China

In recent years,LoRa has been extensively researched in the satellite Internet of Things(IoT).However,the multiple access technology of LoRa is still one of the bottlenecks of satellite *** improve the multiple access performance of LoRa satellite IoT,based on the orthogonality of LoRa symbols in the fractional domain,this paper proposes a low complexity Orthogonal LoRa Multiple Access(OLMA)algorithm for multiple LoRa users occupying the same frequency *** algorithm introduces the address code to divide the fractional bandwidth into multiple parts,and the OLMA users with different address codes occupy different parts to transmit the information code,thus avoiding mutual interference caused by collisions in the same frequency *** multiple access capability of OLMA can be flexibly configured only by simply adjusting the length of the address code according to the actual application requirements of data *** analysis and simulation results show that the OLMA algorithm can greatly improve the multiple access capability and the total transmission bit rate of LoRa IoT without changing the existing LoRa modulation parameters and process.

关键词： LoRa satellite Internet of Things multiple access fractional domain linear frequency modulation

Polar-coded forward error correction for MLC NAND flash memory

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Science China(Information Sciences) 2018年第10期61卷 224-239页

作者： Haochuan SONG Jen-Chien FU Shih-Jia ZENG Jin SHA Zaichen ZHANG Xiaohu YOU Chuan ZHANG lab of Efficient Architectures for digital-communication(LEADS) National Mobile Communications Research Laboratory Southeast University Quantum Information Center of Southeast University National Mobile communications Research laboratory Southeast University Lite-On Technology Corporation School of Electronic Science and Engineering Nanjing University

With the ever-growing storage density, high-speed, and low-cost data access, flash memory has inevitably become popular. Multi-level cell(MLC) NAND flash memory, which can well balance the data density and memory stability, has occupied the largest market share of flash memory. With the aggressive memory scaling, however, the reliability decays sharply owing to multiple interferences. Therefore, the control system should be embedded with a suitable error correction code(ECC) to guarantee the data integrity and accuracy. We proposed the pre-check scheme which is a multi-strategy polar code scheme to strike a balance between reasonable frame error rate(FER) and decoding latency. Three decoders namely binaryinput, quantized-soft, and pure-soft decoders are embedded in this scheme. Since the calculation of soft loglikelihood ratio(LLR) inputs needs multiple sensing operations and optional quantization boundaries, a 2-bit quantized hard-decision decoder is proposed to outperform the hard-decoded LDPC bit-flipping decoder with fewer sensing operations. We notice that polar codes have much lower computational complexity compared with LDPC codes. The stepwise maximum mutual information(SMMI) scheme is also proposed to obtain overlapped boundaries without exhausting search. The mapping scheme using Gray code is employed and proved to achieve better raw error performance compared with other alternatives. Hardware architectures are also given in this paper.

关键词： polar coding non-volatile memory error correcting code NAND flash memory

AI for conceptual architecture:Reflections on designing with text-to-text,text-to-image,and image-to-image generators

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Frontiers of Architectural Research 2024年第3期13卷 593-612页

作者： Anca-Simona Horvath Panagiota Pouliou Research laboratory for Art and Technology Aalborg UniversityAalborg 9000Denmark Lighting Design lab Aalborg UniversityCopenhagen 2450Denmark

In this paper we present a research-through-design study where we employed text-to-text,text-to-image,and image-to-image generative tools for a conceptual architecture project for the eVolo skyscraper *** trained these algorithms on a dataset that we collected and curated,consisting of texts about and images of *** describe our design process,present the final proposal,reflect on the usefulness of such tools for early-stage design,and discuss implications for future research and *** analysing the results from training the text-to-text generators we could establish a specific design brief that informed the final *** results from the image-to-image generator gave an overview of the shape grammars of previous *** results were intriguing and can assist creativity and in this way,the tools were useful for gaining insight into historical architectural data,helped shape a specific design brief,and provoked new *** reflecting on our design process,we argue that the use of language when employing such tools takes a new role and that three layers of language intertwined in our work:architectural discourse,programming languages,and *** present a map that unfolds how these layers came together as a contribution to making machine learning more explainable for creatives.

关键词： Machine learning StyleGAN2-ADA RNN TensorFlow VQGAN+clip AD journal eVolo Conceptual design Architectural design

Innovative Design and Performance Evaluation of a High-speed Bionic Mechanical Leg

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Journal of Bionic Engineering 2015年第3期12卷 352-360页

作者： Hua Nie Ronglei Sun Chaoke Guo Guohua Qin Huiyang Yu State Key lab of digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430070 China

For most legged robots the drive-motors are mounted on the joints of legs, which increase leg＇s mass and rotary inertia. When mounted on legs, the drive-motor has to rotate clockwise and anticlockwise periodically to swing a leg back and forth. Larger inertia of the leg, as well as the ever-changing status of frequent acceleration and deceleration of the motors, limits the moving speed of the legged robots. This article proposes an improved mechanical design to overcome such problems. All the drive-motors are installed on the robot body to reduce the rotary inertia of the legs. Then a crank-rocker mechanism is used to transform continuous rotation of motors to back and forth motion of the leg. With this scheme, the motor may reach higher rotation speed since it drives a lighter leg with no change of the rotation direction. In addition, an elastic tendon is attached to the ankle to reduce the pulse stress on the leg. Kinematics and dynamics analysis demonstrates that the new design enlarges end-workspace, reduces driving torque and increases ground reaction force, which means the new robot has lager stride and higher swing frequency of leg to achieve faster moving.

关键词： high-speed mechanical design bionic leg dynamics