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Improvement of convergence speed for subband adaptive digital filter using the multirate repeating method

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE 1995年第10期78卷 37-45页

作者： Kiya, H Nishikawa, K Ashihara, K Faculty of Technology Tokyo Metropolitan University Hachioji Japan 192-03 Members Kiyoshi Nshikawa graduated in 1990 from the Department of Electrical Engineering Tokyo Metropolitan University where he completed the Master's Program in 1992 and affiliated with Nippon Steel Co. Computer Systems Laboratory. He was a Research Associate in 1993 in the Department of Elect. Inf. Eng. Tokyo Metropolitan University engaged in research onadaptive signal processing and information source coding. He is a member of the IEEE. Associate Member

The subband adaptive system, where the idea of the filter bank is applied to the adaptive filter, has a feature that a higher-order adaptation can be reduced to lower-order adaptations. The reduction of the order of the adaptive filter is related closely to the number of channels and the decimation ratio. The order of adaptive digital filter (ADF) is decreased greatly when the number of subbands is increased, and the decimation ratio is increased up to the maximum value. Then, however, the number of coefficient-updates per unit time is decreased, which results in the deterioration of the convergence Speed. From such a viewpoint, this paper discusses a method to improve the convergence speed, which is deteriorated in the subband adaptive system, due to the decimation. The idea of the proposed method is to utilize effectively the data which have been discarded in the decimation process and to improve the convergence speed. It is called the multirate repeating method. As the first step, the multirate repeating method is applied to the conventional subband adaptive system and the convergence speed is improved. Then a subband adaptive system is introduced in which the multirate repeating method can be utilized more effectively. As a result, a faster convergence is realized while retaining the ADF order-reduction effect, which is an advantage of the subband adaptive system.

关键词： adaptive signal processing subband adaptive system multirate repeating method rational decimation

Numerical simulation of two-dimensional photonic crystal with FDTD method

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Wuhan Ligong Daxue Xuebao/Journal of Wuhan University of Technology 2008年第3期30卷 5-7页

作者： Zhou, Jian Jiang, Hong-Zhou Zhang, Lin Wang, Lin Zeng, Chun-Nian Chen, Ji State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China School of Information Engineering Wuhan University of Technology Wuhan 430070 China School of Automotive Engineering Wuhan University of Technology Wuhan 430070 China Department of Electrical and Computer Engineering University of Houston Houston United States

Based on the theory of photonic crystal and its characteristic, which was known as photonic band gap (PBG), the finite-difference time-domain (FDTD) method, including absorbing boundary condition and periodic boundary condition, was used to simulate transmission characteristic of two-dimensional photonic crystal, which has periodic Al2O3 cylinder array structure. Incident wave was presumed as s-polarized wave. In two incident angles which were 0° and 30°, electric field, phase and transmissivity in the range of 1-30 μm were calculated. Numerical simulation results showed that PBG of photonic crystal existed in the range 12-18 μm (infrared waveband), and it may be used to develop infrared wave-guide.

关键词： FDTD Periodic structure Photonic band gap Photonic crystal

Efficient Image Super-Resolution with Feature Interaction Weighted Hybrid Network

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arXiv 2022年

作者： Li, Wenjie Li, Juncheng Gao, Guangwei Deng, Weihong Yang, Jian Qi, Guo-Jun Lin, Chia-Wen Pattern Recognition and Intelligent System Laboratory School of Artificial Intelligence Beijing University of Posts and Telecommunications Beijing100080 China Intelligent Visual Information Perception Laboratory Institute of Advanced Technology Nanjing University of Posts and Telecommunications Nanjing210046 China Key Laboratory of Artificial Intelligence Ministry of Education Shanghai200240 China Provincial Key Laboratory for Computer Information Processing Technology Soochow University Suzhou215006 China School of Communication and Information Engineering Shanghai University Shanghai200444 China School of Computer Science and Technology Nanjing University of Science and Technology Nanjing210094 China Research Center for Industries of the Future the School of Engineering Westlake University Hangzhou310024 China OPPO Research SeattleWA98101 United States Department of Electrical Engineering National Tsing Hua University Hsinchu30013 Taiwan

Lightweight image super-resolution aims to reconstruct high-resolution images from low-resolution images using low computational costs. However, existing methods result in the loss of middle-layer features due to activation functions. To minimize the impact of intermediate feature loss on reconstruction quality, we propose a Feature Interaction Weighted Hybrid Network (FIWHN), which comprises a series of Wide-residual Distillation Interaction Block (WDIB) as the backbone. Every third WDIB forms a Feature Shuffle Weighted Group (FSWG) by applying mutual information shuffle and fusion. Moreover, to mitigate the negative effects of intermediate feature loss, we introduce Wide Residual Weighting units within WDIB. These units effectively fuse features of varying levels of detail through a Wide-residual Distillation Connection (WRDC) and a Self-Calibrating Fusion (SCF). To compensate for global feature deficiencies, we incorporate a Transformer and explore a novel architecture to combine CNN and Transformer. We show that our FIWHN achieves a favorable balance between performance and efficiency through extensive experiments on low-level and high-level tasks. Codes will be available at https://***/IVIPLab/FIWHN. Copyright © 2022, The Authors. All rights reserved.

关键词： Image reconstruction

Updated radiometric calibration for the Landsat-5 thematic mapper reflective bands

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Updated radiometric calibration for the Landsat-5 thematic m...

作者： Helder, Dennis L. Markham, Brian L. Thome, Kurtis J. Barsi, Julia A. Chander, Gyanesh Malla, Rimy Department of Electrical Engineering and Computer Science South Dakota State University Brookings SD 57007 United States Landsat Project Science Office NASA Goddard Space Flight Center Greenbelt MD 20771 United States Remote Sensing Group Optical Sciences Center University of Arizona Tucson AZ 85721 United States Science Systems and Applications Inc. NASA Goddard Space Flight Center Greenbelt MD 20771 United States Science Applications International Corporation U.S. Geological Survey Center for Earth Resources Observation and Science Sioux Falls SD 57198 United States Image Processing Laboratory South Dakota State University Brookings SD 57007 United States

The Landsat-5 Thematic Mapper (TM) has been the workhorse of the Landsat system. Launched in 1984, it continues collecting data through the time frame of this paper. Thus, it provides an invaluable link to the past history of the land features of the Earth's surface, and it becomes imperative to provide an accurate radiometric calibration of the reflective bands to the user community. Previous calibration has been based on information obtained from prelaunch, the onboard calibrator, vicarious calibration attempts, and cross-calibration with Landsat-7. Currently, additional data sources are available to improve this calibration. Specifically, improvements in vicarious calibration methods and development of the use of pseudoinvariant sites for trending provide two additional independent calibration sources. The use of these additional estimates has resulted in a consistent calibration approach that ties together all of the available calibration data sources. Results from this analysis indicate a simple exponential, or a constant model may be used for all bands throughout the lifetime of Landsat-5 TM. Where previously time constants for the exponential models were approximately one year, the updated model has significantly longer time constants in bands 1-3. In contrast, bands 4, 5, and 7 are shown to be best modeled by a constant. The models proposed in this paper indicate calibration knowledge of 5% or better early in life, decreasing to nearly 2% later in life. These models have been implemented at the U.S. Geological Survey Earth Resources Observation and Science (EROS) and are the default calibration used for all Landsat TM data now distributed through EROS. © 2008 IEEE.

关键词： Landsat

Energy-efficient resource allocation in noma heterogeneous networks

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arXiv 2018年

作者： Zhang, Haijun Fang, Fang Cheng, Julian Long, Keping Wang, Wei Leung, Victor C.M. Engineering and Technology Research Center for Convergence Networks University of Science and Technology Beijing Beijing100083 China School of Engineering University of British Columbia KelownaBCV1X 1V7 Canada College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China Zhejiang Provincial Key Laboratory of Information Processing Communication and Networking Hangzhou310027 China Department of Electrical and Computer Engineering University of British Columbia VancouverBCV6T 1Z4 Canada

Non-orthogonal multiple access (NOMA) has attracted much recent attention owing to its capability for improving the system spectral efficiency in wireless communications. Deploying NOMA in heterogeneous network can satisfy users' explosive data traffic requirements, and NOMA will likely play an important role in the fifth-generation (5G) mobile communication networks. However, NOMA brings new technical challenges on resource allocation due to the mutual cross-tier interference in heterogeneous networks. In this article, to study the tradeoff between data rate performance and energy consumption in NOMA, we examine the problem of energy-efficient user scheduling and power optimization in 5G NOMA heterogeneous networks. The energy-efficient user scheduling and power allocation schemes are introduced for the downlink 5G NOMA heterogeneous network for perfect and imperfect channel state information (CSI) respectively. Simulation results show that the resource allocation schemes can significantly increase the energy efficiency of 5G NOMA heterogeneous network for both cases of perfect CSI and imperfect CSI. Copyright © 2018, The Authors. All rights reserved.

关键词： Heterogeneous networks

Corrections to “Stability of Multidimensional Systems Using Genetic Algorithms”

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IEEE Transactions on Circuits and Systems I: Regular Papers 2005年第9期52卷 1982-1982页

作者： N.E. Mastorakis I.F. Gonos M.N.S. Swamy Department of Computer Science Military Institution Hellenic Naval Academy University Education Piraeus Greece High Voltage Laboratory School of Electrical and Computer Engineering National and Technical University of Athens Athens Greece Center for Signal Processing and Communications Department of Electrical and Computer Engineering Concordia University Montreal QUE Canada

Coherent oscillations of driven rf SQUID metamaterials

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arXiv 2017年

作者： Trepanier, Melissa Zhang, Daimeng Mukhanov, Oleg Koshelets, V.P. Jung, Philipp Butz, Susanne Ott, Edward Antonsen, Thomas M. Ustinov, Alexey V. Anlage, Steven M. Department of Physics CNAM University of Maryland College ParkMD20742 United States Department of Electrical and Computer Engineering University of Maryland College ParkMD20742 United States Hypres Inc. 175 Clearbrook Road ElmsfordNY10523 United States Laboratory of Superconducting Devices for Signal Detection and Processing Kotelnikov Institute of Radio Engineering and Electronics Moscow125009 Russia Physikalisches Institut Karlsruhe Institute of Technology Germany Russian Quantum Center National University of Science and Technology MISIS Moscow119049 Russia

Through experiments and numerical simulations we explore the behavior of rf SQUID (radio frequency superconducting quantum interference device) metamaterials, which show extreme tunability and nonlinearity. The emergent electromagnetic properties of this metamaterial are sensitive to the degree of coherent response of the driven interacting SQUIDs. Coherence suffers in the presence of disorder, which is experimentally found to be mainly due to a dc flux gradient. We demonstrate methods to recover the coherence, specifically by varying the coupling between the SQUID meta-atoms and increasing the temperature or the amplitude of the applied rf flux. Copyright © 2017, The Authors. All rights reserved.

关键词： Metamaterials

A Learning Convolutional Neural Network Approach for Network Robustness Prediction

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arXiv 2022年

作者： Lou, Yang Wu, Ruizi Li, Junli Wang, Lin Li, Xiang Chen, Guanrong The Department of Computing and Decision Sciences Lingnan University Hong Kong The Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai200240 China The College of Computer Science Sichuan Normal University Chengdu610066 China The Department of Automation Shanghai Jiao Tong University Shanghai200240 China The Institute of Complex Networks and Intelligent Systems Shanghai Research Institute for Intelligent Autonomous Systems Tongji University Shanghai201210 China The Department of Control Science and Engineering Tongji University Shanghai200240 China The Department of Electrical Engineering City University of Hong Kong Hong Kong

Network robustness is critical for various societal and industrial networks again malicious attacks. In particular, connectivity robustness and controllability robustness reflect how well a networked system can maintain its connectedness and controllability against destructive attacks, which can be quantified by a sequence of values that record the remaining connectivity and controllability of the network after a sequence of node- or edge-removal attacks. Traditionally, robustness is determined by attack simulations, which are computationally very time-consuming or even practically infeasible. In this paper, an improved method for network robustness prediction is developed based on learning feature representation using convolutional neural network (LFR-CNN). In this scheme, higher-dimensional network data are compressed to lower-dimensional representations, and then passed to a CNN to perform robustness prediction. Extensive experimental studies on both synthetic and real-world networks, both directed and undirected, demonstrate that 1) the proposed LFR-CNN performs better than other two state-of-the-art prediction methods, with significantly lower prediction errors;2) LFR-CNN is insensitive to the variation of the network size, which significantly extends its applicability;3) although LFR-CNN needs more time to perform feature learning, it can achieve accurate prediction faster than attack simulations;4) LFR-CNN not only can accurately predict network robustness, but also provides a good indicator for connectivity robustness, better than the classical spectral measures. © 2022, CC BY.

关键词： Complex networks

TLM MODELING USING AN SIMD computer

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INTERNATIONAL JOURNAL OF NUMERICAL MODELLING-ELECTRONIC NETWORKS DEVICES AND FIELDS 1993年第4期6卷 299-304页

作者： TAN, CC FUSCO, VF The Queen's University of Belfast Department of Electrical & Electronic Engineering Ashby Building Stranmillis Road Belfast BT9 5AH U.K. Chun Chia Tan obtained a first-class honours degree from The Queen's University of Belfast. He was awarded an IEE prize for best final-year project. His current research interests include the modelling of electromagnetic fields using parallel processing techniques. At present Mr Tan is working as an electrical engineer in Malaysia. Vincent F. Fusco was educated at The Queen's University of Belfast where he obtained the degree of Ph.D. He has worked as a research engineer on short-range radar and radio telementry systems. Currently he is a Reader in Microwave Commnications in the School of Electrical Engineering and Computer Science The Queen's Univeristy of Belfast. His current research interests include non-linear microwave circuit simulation and concurrent programming techniques for electromagnetic field problems. He has acted as consultant to a number of major companies and has published numerous research papers in these areas. He is author of the bookMicrowave Circuits Analysis and Computer Aided Design(Prentice Hall 1987). Dr Fusco is a Chartered Electrical Engineer and a Member of the Institute of Electrical Engineers.

A major limitation of the transmission-line matrix (TLM) method used to solve Maxwell's equations is the long computation time required. The TLM scattering calculations involved can, however, be viewed as parallel in nature. This paper describes an effort to reduce computational time by using an SIMD, DAP multiprocessor computer employed to solve a two-dimensional TLM electromagnetic field formulation. A parallel algorithm based on the TLM scattering algorithm is designed and implemented using FORTRAN-PLUS Enhanced on an AMT DAP 510 machine. Here the connectivity of the DAP is exploited to simulate the intrinsic scattering behaviour on which the TLM algorithm relies. The results show that parallel processing on an SIMD machine such as the DAP is advantageous, especially for higher-order mesh sizes.

关键词： Electric lines