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Conference on Laser Communication and Propagation through the Atmosphere and Oceans V

作者： Gaire, Sunil Kumar Faruque, Saleh Ahamed, Md. Maruf Univ North Dakota Dept Elect Engn Grand Forks ND 58202 USA

ISBN: (数字)9781510603523

ISBN: (纸本)9781510603493;9781510603509

Laser based radio communication system, i.e. OptoRadio, using Orthogonal M-ary PSK Modulation scheme is presented in this paper. In this scheme, when a block of data needs to be transmitted, the corresponding block of biorthogonal code is transmitted by means of multi-phase shift keying. At the receiver, two photo diodes are cross coupled. The effect is that the net output power due to ambient light is close to zero. The laser signal is then transmitted only into one of the receivers. With all other signals being cancelled out, the laser signal is an overwhelmingly dominant signal. The detailed design, bit error correction capabilities, and bandwidth efficiency are presented to illustrate the concept.

关键词： OptoRadio Laser Communication error control coding Orthogonal Code M-ary PSK photo-receptor Optical Wireless Communication Bandwidth Efficiency

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XPRESS TRANSFER PROTOCOL IN A MEDICAL COMMUNICATION-SYSTEM

XPRESS TRANSFER PROTOCOL IN A MEDICAL COMMUNICATION-SYSTEM

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Conference on PACS: Design and Evaluation

作者： LIM, CK MAYDELL, UM UNIV ALBERTA DEPT COMP SCIEDMONTON T6G 2H1ABCANADA

ISBN: (纸本)0819414603

For a local area medical network, the performance of transfer protocols on top of the standard LAN protocols is explored. In this simulation the medical LAN is FDDI at 100 Mbps and the transfer protocols to be investigated are the commonly available TCP/IP and the relatively new, lightweight XTP. The performance measures used for their comparison are response time for an image and total transfer time for a series of images in one examination The image workloads ranged from current, potential digital image loads to larger image transmission loads in the future. Two different values for FDDI's target-token-rotation-time were also explored. Contrary to expectations XTP using less overhead bits than TCP/IP did not greatly outperform TCP/IP.

关键词： Local area networks Image transmission Digital imaging Receivers X-rays error control coding X-ray imaging Medical imaging Telecommunications Ultrasonography

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FPGA implementation of a Micro controller Unit for Body Sensor Network 1

FPGA implementation of a Micro controller Unit for Body Sens...

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1st International Conference on Computational Techniques, Electronics and Mechanical Systems (CTEMS)

作者： Mavinkattimath, Swati G. Khanai, Rajashri Torre, Dattaprasad A. KLE Dr MSSCET Belagavi Elect & Communiicat Belagavi India KLS Gogte Inst Technol Elect & Communiicat Belagavi Karnataka India

ISBN: (纸本)9781538677094

The small wireless body sensors and variety of medical devices have influenced the expansion of Body Sensor Networks (BSNs). However, in BSNs, wireless transmissions are exposed to a variety of active and passive security attacks. As a result, safety of private information collected from BSNs is of high importance. Hence this paper presents a design of a Micro control Unit (MCU) for BSNs. The microcontroller consists of a register bank, a predictor, an encryption block, an error control coding (ECC) circuit and transmitter. The register bank is used to store the input signal values. The predictor is used to compress the signal adaptively. Furthermore, an encryption method uses a technique to protect the private information during transmission. Although the encryption protects the private signal, there is possibility that the data may get corrupted or lost during transmission. Hence ECC technique is used to find errors during transmission.

关键词： Predictor Register bank error control coding encryption FPGA

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Recovery of partially occluded speech segments using Hopfield neural network

Recovery of partially occluded speech segments using Hopfiel...

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10th Conference on Automatic Target Recognition

作者： Jouny, I Macdonald, B Lafayette Coll Dept Elect & Comp Engn Easton PA 18042 USA

ISBN: (纸本)0819436763

This paper focuses on utilizing the associative capabilities of the Hopfield neural net in processing digitized speech and recovering erroneous speech segments and reconstructing noisy speech. The scope of this study is limited and the tests conducted are exploratory in nature. However, with a limited vocabulary that fits many practical applications, this study shows that digitized speech can be enhanced using properly trained recurrent networks such as the Hopfield neural net. The results indicate that a Hopfield neural network with sufficient associative memory can be used in a limited vocabulary context to reconstruct digitized speech with noisy, erroneous, and occluded or silenced segments.

关键词： Neural networks Signal to noise ratio Neurons Contamination Data communications Content addressable memory Interference (communication) Telecommunications error control coding Internet

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Variable Data Rate Vocoder Improvements For Secure Interoperable DoD Voice Communication

Variable Data Rate Vocoder Improvements For Secure Interoper...

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IEEE Military Communications Conference

作者： Heide, David A. Cohen, Aaron E. Lee, Yvette T. Moran, Thomas M. US Naval Res Lab Washington DC 20375 USA

ISBN: (纸本)9780769551241

One intermediate goal towards achieving universal secure voice interoperability in the Department of Defense (DoD) has been the development of a universal voice encoder (vocoder). This vocoder would seamlessly encode speech at a wide range of interoperable variable and fixed data rates to suit a wide range of DoD communication equipment. This paper describes the most important features of such a vocoder and recent advancements in achieving this goal. Specifically this paper will describe three main areas: 1) Summary of the variable data rate (VDR) algorithm and the most recent improvements to the vocoder. 2) Methods for transcoding between fixed rate and variable data rate vocoding modes. 3) Summary of heavily bit error protected, fixed-rate modes.

关键词： MELPe Variable rate vocoding error control coding secure radio communication error correction codes Vocoders United States Department of Defense Data transfer rates variable data PIN1 gene Interoperability transcoding

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DESIGN AND CHARACTERIZATION OF A 20-GBIT/S CLOCK RECOVERY CIRCUIT

DESIGN AND CHARACTERIZATION OF A 20-GBIT/S CLOCK RECOVERY CI...

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Conference on Fiber Optic Network Components

作者： MONTEIRO, P MATOS, JN GAMEIRO, A DAROCHA, JF UNIV AVEIRO DEP ELECTR & TELECOMMUNP-3800 AVEIROPORTUGAL

ISBN: (纸本)0819418005

In this communication we report the design of a clock recovery circuit produced for the 20 Gbit/s demonstrator of the RACE 2011 project `TRAVEL' of the European Community. The clock recovery circuit is based on an open loop structure using a dielectric resonator narrow bandpass filter with a high quality factor. A detailed electrical characterization of the circuit and also its sensitivity to temperature and detuning variations are presented. The experimental results show that the circuit is a very attractive solution for the forthcoming STM-128 optical links.

关键词： Clocks error control coding Dielectric filters Dielectrics Optical filters Electronic filtering Resonators Bandpass filters Manufacturing Receivers

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Shape control of circular plate with piezoelectric sheet actuators

Shape control of circular plate with piezoelectric sheet act...

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Smart Structures and Materials 2001 Conference

作者： Philen, MK Wang, KW Penn State Univ Struct Dynam & Controls Lab University Pk PA 16802 USA

ISBN: (纸本)0819440132

In recent years, there has been a surge of interest in using piezoelectric patches attached to optical surfaces in hope of attaining high precision of optical mirrors with minimal additional weight. Based on results from preliminary investigations, the configuration of thin piezoelectric strip actuators placed in the radial and circumferential line directions of a circular plate (host structure of the mirror) is chosen to control the surface error of the mirror. The major challenges here is the two dimensional actuation effect of the actuator patches, which could induce high order modal deformations and increase the difficulty of surface error control. The purpose of this research is to investigate such effects and propose solutions. A simple model is first developed through Hamilton's principle and discretized using Galerkin's method, thus giving a set of differential equations describing the coupled mechanical and electrical systems. From the equations, the coupling between the electrical and structural systems for each mode shape can be calculated, thus giving a means to maximize the coupling between the actuator and the mode shapes of interest by changing the actuators' properties. Likewise, the properties can be tailored such that excitation of the unwanted modes can be avoided or reduced. A more comprehensive finite element model is also derived to validate the observations obtained from the simple model. From the analysis, it is found that decoupling the circumferential action from the radial action of the piezoelectric patches can dramatically improve the performance of the controller, thus achieving a greater reduction in the surface error. Methods to decouple the circumferential strain from the radial strain are then proposed.

关键词： Actuators Mirrors Finite element methods error control coding Monochromatic aberrations Partial differential equations Systems modeling Zernike polynomials Chemical elements error analysis

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A Novel High rate LDPC code 20

A Novel High rate LDPC code

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21st International Conference on Distributed Computing and Networking (ICDCN)

作者： Pramanik, Ankita Das, Avik Kumar Indian Inst Engn Sci & Technol Howrah W Bengal India

ISBN: (纸本)9781450377515

In IoT applications with remote monitoring, the data is transferred through a wireless channel. To ensure data reliability, error control coding is essential. For the high error correcting ability, the Low density parity check (LDPC) codes are used as the most popular code for error-control in many domains like telecommunication, magnetic-recording, radio application, etc. Thus the data transmitted in IoT system may be encoded by LDPC codes. This paper presents a small length LDPC code of six-by-seven. The shifted identity matrix and a lower staircase matrix are used to construct the LDPC code. These codes have very low encoding complexity. Belief-propagation is used to decode the code. In the simulation result of the code, improved performance in bit error rate is shown. The simulation result of these codes shows a good performance in the bit-error-rate.

关键词： Low Density Parity Check(LDPC) WiMax quasi-cyclic error control coding

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Permutation Spreading for Asynchronous MIMO-CDMA Systems Using Hadamard Codes and Gold Scrambling Sequences

Permutation Spreading for Asynchronous MIMO-CDMA Systems Usi...

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IEEE Wireless Communications and Networking Conference

作者： D'Amours, Claude Dahmane, Adel Omar Univ Ottawa Sch Informat Technol & Engn Ottawa ON K1N 6N5 Canada Univ Quebec Trois Rivieres Elect & Comp Engn Dept Trois Rivieres PQ Canada

ISBN: (纸本)9781424429479

Permutation spreading has been proposed as an alternative technique for assigning spreading codes to the different transmit antennas of a user in a Multiple Input Multiple Output Code Division Multiple Access (MIMO-CDMA) system. In this paper, we propose the use of the permutation spreading technique using Hadamard codes for antenna separation and Gold scrambling codes for user separation. All users are assigned the same set of Hadamard sequences, thus our proposed technique reduces the overall number of spreading sequences required by the system. In the example shown in the paper, the proposed spreading combination allows both an increase in spectral effciency and a four-fold decrease in the number of spreading codes needed by the system. Moreover, permutation spreading shows more than 7dB advantage over conventional MIMO-CDMA system in a heavily loaded environment.

关键词： CDMA error control coding Frequency selective channels Maximum likelihood detection MIMO

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Hardware Implementation of Two Key Equation Solvers for Reed-Solomon Decoding

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IEEE LATIN AMERICA TRANSACTIONS 2015年第11期13卷 3550-3555页

作者： Grimm, T. Bezerra, E. A. Silva, D. Univ Fed Santa Catarina Florianopolis SC Brazil Univ Fed Santa Catarina Dept Engn Eletr Area Sistemas Embarcados Pplicacoes Espaciais Florianopolis SC Brazil Univ Fed Santa Catarina Dept Engn Eletr Grp Pesquisas Comunicacoes GPqCom Florianopolis SC Brazil

Reed-Solomon codes are widely used to provide reliable communication, as they are well known for their high data correction rates. However, techniques that best optimize hardware area as well as signal propagation delays are needed in today's applications. In this work, two techniques are investigated and implemented using a hardware description language, synthesized to a XUPV5-LX110t development platform, and compared to commercial solutions.

关键词： error control coding Reed-Solomon Key Equation Solver Reconfigurable Hardware

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