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Orthogonal fluxgate employing discontinuous excitation

JOURNAL OF APPLIED PHYSICS 2010年第9期107卷 09E717-1-09E717-3页

作者： Weiss, Eyal Paperno, Eugene Plotkin, Anton Ben Gurion Univ Negev IL-84105 Beer Sheva Israel Soreq NRC Div Appl Phys IL-81800 Yavne Israel Weizmann Inst Sci IL-76100 Rehovot Israel

In this work, we suggest a new method for the reduction of the power consumption of an orthogonal fluxgate employing an amorphous wire. In order to reduce the power consumption, we introduce idle intervals in the fluxgate excitation. In fluxgates where the excitation current is applied directly to the wire core, the excitation wave form can easily be manipulated due to the very small impedance of the wire core. the resulted discontinuities in the excitation increase the fluxgate noise by a factor of about 3.5. In order to eliminate this excess noise, we simply discard the data related to the excitation idle intervals from the signal processing of the fluxgate output. As a result, we have reduced the fluxgate power consumption by a factor of 16, from 6.4 mW at 100% duty cycle down to 0.4 mW at 6.25% duty cycle. It is important to note that the reduction of power consumption is obtained without decreasing the fluxgate resolution. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3360632]

关键词： signal processing INFORMATION measurement NANOWIRES NANOSTRUCTURED materials QUANTUM electronics

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the dynamics of the MAPK network 9

The dynamics of the MAPK network

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9th International Workshop on data Mining in Bioinformatics, BIOKDD 2010, Held in Conjunction with 16th ACM SIGKDD conference on Knowledge Discovery and data Mining

作者： Policeanu, Ioana Menezes, Ronaldo Computer Sciences Florida Tech MelbourneFL United States

ISBN: (纸本)9781605583020

Mitogen-activated protein kinase (MAPK) is one of the most important and highly studied signal transduction molecules, being often associated with cancer and auto-immune diseases. the network which carries its name connects cell-surface receptors to specific transcription factors and other regulatory proteins that are responsible for numerous cellular activities including growth, proliferation, cell differentiation and survival. Recent advances in the field of Network Sciences improved our understanding of networks as frameworks to model interactions, such as the ones encountered in the MAPK network. However, even with the development of high-throughput techniques, the complexity of biological networks presents researchers with various challenges, such as sampling from sub-networks and analyzing incomplete datasets. In this paper, we made use of the directed MAPK network reconstructed starting from 1980 data, and the updates recreated every four year following that. Once the present state was reached, we compared all reconstructions to instances from a similar undirected network, as well as a randomized network with the same number of nodes and edges as the directed one, which served as a control. Based on the results of our experiments we concluded that MAPK displays scale-free and small-world characteristics only with newer instances, when the majority of the MAPK network components had been discovered. By analyzing the evolution of the MAPK network over the years and observing the topology and structure transformations that occurred in the network, we were able to pinpoint not only the type of dynamic network MAPK encompasses and its most significant proteins that can be targeted for drug treatments, but also the important fact that completeness might not be achieved in certain networks. this is a crucial aspect when examining biological networks, since scientists assume that the latest maps available are complete and error-proof. Copyright © 2010 ACM.

关键词： signal transduction

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Development of a small and long-life ultrasonic biotelemetry system strong against sea ambient noise

Development of a small and long-life ultrasonic biotelemetry...

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20th International Congress on Acoustics 2010, ICA 2010 - Incorporating the 2010 Annual conference of the Australian Acoustical Society

作者： Miyamoto, Yoshinori Takao, Yoshimi Sasakura, Toyoki Tokyo University of Marine Science and Technology 4-5-7 Konan Minato-ku Tokyo 108-8477 Japan National Research Institute of Fisheries Engineering 7620-7 Hasaki Kamisu Ibaraki 314-0408 Japan Fusion Incorporation 1-1-1-806 Daiba Minato-ku Tokyo 135-0091 Japan

ISBN: (纸本)9781617827457

A highly efficient ultrasonic biotelemetry system would be desired to the ocean having a high underwater ambient noise that is especially from the temperate zone to the tropics. the four parameters were defined as the estimated factors for pinger system, long distance transmitting, battery life, pinger size and ability of recognition. the four parameters of the pinger were analyzed and investigated to design for the optimum ultrasonic biotelemetry system. the first parameter, long distance, must be considered the transmitting frequency, modulation, transformation and etc. the second, battery life, must be designed for the effective transducer and the low power dissipation electronic circuit. the third, smallest pinger size, must be adopted the microelectronics components. the last, high recognition, depend on the signal processing method of the underwater transmitting system . As a result, the first need was achieved over 1,200 meters transmission distance, the second was realized 300 days battery life when 30 seconds repetition by using the small battery SR626SW 32mAh. the third, the pinger size was realized theφ8 mm diameter and 40 mm long. the last, the M sequence signal was used the pinger and the correlation processing of the receiving system was adopted for the high recognition against the noise and to avoid the collision of other pingers. the system consisted of the tiny pinger and the high performance receiving equipment including the transducer. the pinger could be transmitted the IDs and the depth information each repetition interval. the receiver processed to correlate the received Msequence signal from the pinger using the FPGA chip and calculates the direction of the pinger. the raw data could be stored to the PC through the data conversion from analog to digital, 16 bits 192 kHz sampling. the actual experimental data will be presented to obtain in the Tokyo Bay and Osaka Bay using the developed system. Copyright © (2010) by the International Congress o

关键词： Low power electronics

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Multi-radar system database integration using metrized small world technology

Multi-radar system database integration using metrized small...

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International conference on Microwaves, Radar and Wireless Communications

作者： Dmitry Ponomarev Vladimir Krylov Yuri Pankratov Mera Laboratories Nizhny Novgorod Russia

the present article describes the possibility of integrating the data from several radars with shared radiolocation areas in order to acquire precise information about the targets by means of analyzing the events in neighboring spatiotemporal resolution elements. the paper suggests an algorithm for integrating the data based on creating the graph which possesses the characteristics of the “Metrized small World”. A possibility of processing the integrated data in real time is analyzed. the article describes efficient metrics for integrating multi-radar data into a single Metrized small World graph. Examples of such algorithms are given.

关键词： Spatial databases Spatial resolution Bandwidth Costs data analysis Distributed databases Radar scattering signal resolution Information analysis Spatiotemporal phenomena

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Sparsity enhanced fast subsurface imaging for stepped frequency GPRs

Sparsity enhanced fast subsurface imaging for stepped freque...

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IEEE signal processing and Communications Applications (SIU)

作者： Mehmet Ali Çağrı Tuncer Ali Cafer Gürbuz Elektrik ve Elektronik Mühendisliği Bölümü TOBB Ekonomi ve Teknoloji Üniversitesi Turkey

A sparsity enhanced and fast data acquisition and imaging method is presented for stepped-frequency continuous-wave ground penetrating radars (SFCW GPRs). In previous work it is shown that if the target space is sparse like the point like targets, an image of the target space can be constructed with making measurements at only a small number of random frequencies by solving an l 1 minimization problem. this greatly reduces the data acquisition time but the computational complexity for the imaging method is high. In this work, subsurface imaging is done with a suboptimal but fast method, orthogonal matching pursuit. Similar results to l 1 minimization images are obtained within much shorter times. Also the results are sparse and less cluttered compared to standard backprojection images.

关键词： Ground penetrating radar Matching pursuit algorithms Radar imaging data acquisition Compressed sensing

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ASPEN: An Asynchronous signal Processor for Energy Efficient Sensor Nodes

ASPEN: An Asynchronous Signal Processor for Energy Efficient...

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IEEE International conference on Electronics, Circuits and Systems (ICECS)

作者： Soumik Ghosh Jared Tessier Magdy A. Bayoumi Center of Advanced Computer Studies University of Louisiana Lafayette Lafayette LA USA

For ubiquitous wireless sensor networks, there are three main requirements. the devices must be extremely small, consume very little operating power, and capable of distributed signal processing to enable in situ processing of sensed data at leaf nodes of the network. this paper presents the design of an Asynchronous Digital signal Processor (ASPEN) to realize these goals. Using Quasi-delay insensitive (QDI) asynchronous templates in the processor core, the energy consumption per instruction is reduced, while performing Digital signal Processor (DSP) tasks. the processor takes advantage of multiple functional blocks, which are activated only when an instruction requiring their use is found in the instruction queue. the primary processor pipeline resembles that of a microcontroller while other units remain dormant until an instruction using them arrives in the queue. Functional blocks implemented include an asynchronous FFT core and a DSP datapath. the processor has been designed in a commercial 90 nm process. It consumes less than 10 pJ/instruction for ALU computations, and up to 80 pJ/operation for instruction fetch and decode operations. the FFT unit consumes 132 pJ for a 16-point FFT.

关键词： Energy efficiency Electromagnetics Indexes Pipelines Coprocessors

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Detection and Localization of Multiple Unresolved Extended targets via Monopulse Radar signal processing

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IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS 2009年第2期45卷 455-472页

作者： Zhang, Xin Willett, Peter Bar-Shalom, Yaakov United Technol Res Ctr E Hartford CT 06108 USA Univ Connecticut Dept Elect & Comp Engn Storrs CT 06269 USA

When the size of targets is comparable to the range resolution of monopulse radars, these targets should be considered as extended rather than point targets. If several closely-spaced targets fall within the same radar beam and between adjacent matched filter samples in range, the full monopulse information from all of these samples can and should be used to resolve these targets, i.e., estimate the number of targets and their respective angles-of-arrival and ranges. To detect and localize multiple unresolved extended targets, we establish a model for monopulse radar returns from extended objects, and present a maximum likelihood estimator (MLE) to localize the targets. Rissanen's minimum description length (MDL) criterion will be used to decide the number of existing extended objects. We also derive the upper limit on the number of targets and their scattering centers that can be resolved, and we provide necessary conditions for these targets to be uniquely identified. We compare the new extended target monopulse processing scheme with previously developed point-target monopulse techniques in the simulations.

关键词： RADAR ELECTRONIC pulse techniques ELECTRONIC systems signal processing -- Digital techniques MACHINE theory

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OPTICAL STEGANOGRAPHY FOR data HIDING IN OPTICAL NETWORKS

OPTICAL STEGANOGRAPHY FOR DATA HIDING IN OPTICAL NETWORKS

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16th International conference on Digital signal processing

作者： Prucnal, Paul R. Fok, Mable P. Kravtsov, Konstantin Wang, Zhenxing Princeton Univ Dept Elect Engn Princeton NJ 08544 USA

ISBN: (纸本)9781424432974

Optical steganography for data-hiding is experimentally demonstrated using group velocity dispersion in an optical network. A stealth channel is temporally and spectrally hidden underneath a public channel. Our technique applies to several different types of optical systems including optical code division and wavelength division multiplexing. the hidden signal is retrieved at the receiver through dispersion management. the effect of the stealth channel on the performance of the public channel is shown to be small;this is demonstrated through eye diagrams and bit-error rate measurements. To miniaturize the proposed scheme, compact chirped fiber Bragg gratings are used, reducing the length of the fiber providing group velocity dispersion is by a factor of 2000 compared to previous demonstrations.

关键词： Optical steganography data-hiding group velocity dispersion chirped fiber Bragg gratings

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SEPARATING AND TRACKING ERP SUBCOMPONENTS BY CONSTRAINED PARTICLE FILTERING

SEPARATING AND TRACKING ERP SUBCOMPONENTS BY CONSTRAINED PAR...

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16th International conference on Digital signal processing

作者： Jarchi, Delaram Abadi, Bahador Makki Sanei, Saeid Cardiff Univ Sch Engn Ctr Digital Signal Proc Cardiff S Glam Wales

ISBN: (纸本)9781424432974

In this paper a new method based on particle filtering for separating and tracking event related-potential (ERP) subcomponents in different trials is presented. the latency and amplitude of each ERP subcomponent is formulated in the state space model. Based on some knowledge about ERP subcomponents, a constraint on the state space variables is provided to prevent the generation of invalid particles and also make use of a small number of particles which are most effective especially in high dimensions. the method is applied on the simulated and real P300 data. the algorithm has the ability of tracking P300 subcomponents i.e. P3a and P3b, in single trials even in the low signal-to-noise ratio situations.

关键词： Event related potential (ERP) Particle filter constraint subcomponent P300

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A 64 Channels 14-Bit 50 MS/sec data Acquisition Card with Real Time processing in VME Form Factor.

A 64 Channels 14-Bit 50 MS/sec Data Acquisition Card with Re...

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16th IEEE/NPSS Real-Time conference

作者： Martin, J-P Mercier, C. Starinsky, N. Univ Montreal Lab Rene JA Levesque Montreal PQ H3C 3J7 Canada

ISBN: (纸本)9781424457960

A 64 channels digitizer card has been designed for the readout of auxiliary detectors at the TRIUMF ISACII TIGRESS facility. the card has been optimized for the readout of silicon strip detectors and scintillator arrays. However, it is general enough in functionality to be adaptable for most applications. Each channel consist of a 50 MS/sec 14-bit ADC with LVDS serial output (at 700 MHZ). the high density of the card is made possible by the use of small footprint octal ADC chips. Groups of 4 octal ADC's have their fast serial outputs connected to Altera Stratix FPGA'S that read out the data streams and perform the required real time processing of the digitized signals. For the silicon detector application, the processing is essentially to apply pole-zero compensation, perform the digital filtering of the preamplifiers pulse shapes, evaluate the charge, and calculate a time stamp. the module is laid out in the standard VME 6U 4HP format, and consists of two types of assemblies: a VME carrier board that contains a data assembler, general services and I/O interfaces, and two mezzanines that contain the ADC's and the signal processing FPGA's. the module can be accessed through the VME bus, but also has a fast CAT6 serial LVDS serial communication link compatible with the TIGRESS readout system.

关键词： Field programmable gate arrays (FPGA)

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