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Research directions for future generations of cochlear implants

Cochlear Implants International 2004年第SUPPL. 1期5卷 2-8页

作者： Clark, Graeme Department of Otolaryngology The Bionic Ear Institute ARC Ctr. for Nanostruct. Electromat. East Melbourne Vic. 3002 384 Albert Street Australia

Physiological and psychophysical research indicates that improved hearing in noise and music appreciation are likely with cochlear implants, with better reproduction of the fine temporospatial patterns of neural response in the auditory pathways due to phase differences in neuron firing patterns as the result of the basilar membrane travelling wave. An initial speech-processing strategy, to in part reproduce this information, is showing better frequency discrimination and musical perception. However, more exact reproduction is likely with a new generation electrode array which could involve the use of neurotrophins and inherently conducting polymers. The siting and design of this, as well as safety, needs further investigation before it is implemented. 2004 ©Whurr Publishers Ltd.

关键词： Cochlear implants frequency coding Neurotrophins

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16-Sensor Passive Wireless SAW Humidity Sensor System

16-Sensor Passive Wireless SAW Humidity Sensor System

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IEEE International frequency Control Symposium (IFCS)

作者： Hines, J. H. Solie, L. P. Cote, G. O. Corey, J. D. Tucker, D. Y. G. Hines, A. T. Borguet, E. U. Appl Sensor Res & Dev Corp Arnold MD USA Temple Univ Philadelphia Dept Chem Philadelphia PA USA

ISBN: (纸本)9781457718199

This paper describes the development, operating principles, and experimental performance of sixteen uniquely identifiable, wirelessly interrogable, passive surface acoustic wave (SAW) humidity sensors, and a prototype wireless transceiver capable of reading the set of sensors and interpreting individual sensor responses. The set of sensors was produced using a combination of discrete frequency coding and time diversity, and can operate simultaneously in groups of 8 or more while retaining the ability to individually identify and read each sensor. Nanostructured polyvinyl pyrrolidone/lithium chloride doped titanium dioxide sensing layers developed in collaboration with researchers from Temple University were utilized on the SAW die to produce sensors that demonstrate large, rapid, reversible quantitative responses to humidity exposure in laboratory conditions. The transceiver implemented a differential time integrating correlator based system architecture. The system operates in a manual mode for sensor selection, and utilizes a PC-based LabView user interface for data acquisition and system control. This system was shown to be capable of reading the humidity sensors wired and wirelessly over short range (up to 10 feet) under laboratory conditions. Toggling of transmit (Tx) and receive (Rx) antenna operation was required to eliminate high Tx to Rx crosstalk levels caused by continuous transmission and reception, which otherwise would prevent wireless reading of passive sensors. The wireless sensor system was successfully demonstrated at NASA Kennedy Space Center in November, 2011.

关键词： Sensors Sensor systems wireless Humidity sensors frequency coding Transceivers continuous transmission experimental performance time diversity reception reading TOGGLE

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Microgrid Light-Load Efficiency Improvement Based on Online-Inverter Detection 13

Microgrid Light-Load Efficiency Improvement Based on Online-...

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13th IEEE Energy Conversion Congress and Exposition (IEEE ECCE)

作者： Sheykhi, Ali Ashtiani, Nima Amouzegar Khajehoddin, S. Ali Univ Alberta Dept Elect & Comp Engn Edmonton AB Canada

ISBN: (纸本)9781728151359

Droop-controlled inverters are widely used in microgrids to supply the load demand. However, due to low light-load efficiency of inverters, the conventional droop control used for proportional power sharing among inverters does not guarantee an optimal system efficiency at light loads. This paper presents a decentralized online-inverter detection (OID) method based on a transient coded frequency deviation such that the OID detects the online inverters in light-load situations and determines the required minimum number of inverters with the lowest rated powers to supply the loads and improve the overall efficiency. As a result, all the selected inverters will operate at higher power levels and thus, at a higher efficiency compared with the case where all of the inverters shared the power and operated at low power levels. To study the effectiveness of the method, the OID is applied to a system with three single-phase parallel inverters, and an efficiency improvement of 8% is obtained at light loads. Moreover, experimental results are provided to evaluate the performance of the OID in practice.

关键词： Decentralized control droop control microgrid efficiency improvement frequency coding light-load power sharing online-inverter detection parallel inverter systems

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3D Sonar System based on Mills Cross Antenna Configuration

3D Sonar System based on Mills Cross Antenna Configuration

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Oceans Conference

作者： Degel, C. Fonfara, H. Welsch, H. J. Becker, F. J. Hewener, H. Fournelle, M. Tretbar, S. H. Fraunhofer Inst Biomed Engn Div Ultrasound Ensheimer Str 48 D-66386 St Ingbert Germany

ISBN: (纸本)9781479949182

A special aperture for a 3D sonar system is the so called Mills Cross antenna configuration. The Mills Cross arrangement looks like a "T" in which both antennas have a special function. In our work one antenna, consisting of 128 piezoelectric transducer elements, is used to transmit sound into a volume of interest. The second one, also made of 128 piezoelectric transducers, is used for receiving the reflections from objects or surfaces in the vicinity of the antennas. Each transducer element has a convex curvature to cover at least 30 degrees of the elevational direction. With that a volume defined by sector angles of 30 degrees x 30 degrees can be measured. To achieve fast volumetric imaging a frequency coding is used to transmit signals in different directions at the same time. The received signals are decoded to determine the different signals coming from the different directions. In this work we present the basic working principals of the system and the first measurement results.

关键词： antenna arrays array signal processing piezoelectric transducers sonar signal processing 3D sonar system Mills Cross antenna configuration convex curvature frequency coding mills cross antenna configuration volumetric imaging Acoustic measurements Antenna measurements Antennas Sea measurements Sonar measurements Transducers

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frequency CODED QUANTUM KEY DISTRIBUTION CHANNEL BASED ON PHOTON AMPLITUDE-PHASE MODULATION

FREQUENCY CODED QUANTUM KEY DISTRIBUTION CHANNEL BASED ON PH...

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Conference on Systems of Signal Synchronization, Generating and Processing in Telecommunications (SINKHROINFO)

作者： Gabdulhakov, Ildaris M. Morozov, Oleg G. PJSC Tattelecom 57 N Ershov St Kazan 420061 Russia Kazan Natl Res Tech Univ 10 K Marx St Kazan 420111 Russia

ISBN: (纸本)9781538617861

The technology of frequency coding in channels of quantum key distribution allows to determine the ground state of photons through the value of the amplitude of its carrier, frequency modulated in phase (PM) or amplitude (AM) by a radio-frequency signal, and the resulting side components. Over the past twenty years, it has been substantially modified and improved. At the same time, in recent works, an expanded understanding of the frequency coding principle is used, in which each photon state is associated not with the phase of the modulating signal at a certain frequency, but with one or more sideband frequencies or the carrier frequency of the photon itself. The known schemes of electro-optical modulation and remodulation are described by the symmetric pairs PM-PM, AM-AM and AM-PM (PM-AM), where the first component determines the modulator type on the Alice side (legal subscriber - transmitter), and the second one on the side of Bob legal subscriber - receiver). It is noted, that the smallest value of QBER is achieved in schemes with a passive definition of one or two basic states of a photon, i.e. without the use of remodulation processes. The formation of a filter system is carried out using fiber Bragg gratings (FBG) or arrayed waveguide gratings (AWG), tuned to the photon carrier or it sideband components. In this paper, we present the results of constructing a universal system of quantum key distribution (QKD) based on the electro-optical AMPM-PMAM scheme, which makes it possible to realize all the above-mentioned schemes and additionally combined version. At the heart of the AMPM-PMAM system of the QKD system is the modulation transformation of the photon carrier based on the Il'inMorozov's method and its one-and two-modulator realizations. For the mathematical description of the scheme, the principles of constructing a single-port modulation microwave photonic link of a sequential type and photon modeling of electro-optical modulators were used. The use of

关键词： quantum cryptography quantum key distribution frequency coding electro-optical photon modulation amplitude-phase tandem modulation

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Parent-Child Interaction in Children with Autism Spectrum Disorder and Their Siblings: Choosing a coding Strategy

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JOURNAL OF CHILD AND FAMILY STUDIES 2018年第1期27卷 91-102页

作者： Bontinck, Chloe Warreyn, Petra Meirsschaut, Mieke Roeyers, Herbert Univ Ghent Dept Expt Clin & Hlth Psychol Henri Dunantlaan 2 B-9000 Ghent Belgium Univ Ghent Dept Expt Clin & Hlth Psychol Ghent Belgium Artevelde Univ Coll Ghent Belgium

The parent-child interaction strongly influences the emotional, behavioural, and cognitive development of young children. The nature of parent-child interactions differs in families with children with autism spectrum disorder (ASD), but research still entails a lot of inconsistencies and there is no consensus as to how these interactions should be coded. The parent-child interaction between sixteen mothers and their child with ASD (M (age) = 68 months) and a younger sibling without ASD (M (age) = 48 months) in a within-family study were coded using both a global and frequency coding scheme. Global and frequency codes of the same sample were compared to explore the value of each coding method and how they could complement each other. In addition, each coding method's ability to detect group differences was evaluated. We found that mothers used an interaction style characterized by more support and structure, and clearer instructions in interaction with their children without ASD. In addition, global rating results suggested that within the ASD group, mothers may adapt their behaviour to the specific abilities of their child. Regarding the evaluation of coding method, results showed overlap between conceptually similar constructs included in both coding schemes. Although frequency coding clearly has its value, more qualitative aspects of the interaction were better captured by global rating scales and global rating was more time efficient. For this purpose, global ratings might be preferable over frequency coding.

关键词： Autism spectrum disorder Parent-child interaction Global coding frequency coding Within-family design

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Research on Waveform Design of Multi-Carrier Phase Coded and frequency Modulation Signal

Research on Waveform Design of Multi-Carrier Phase Coded and...

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2021 CIE International Conference on Radar, Radar 2021

作者： Luo, Si Li, Chuanming Wang, Luchao Ji, Shiyong Beijing Institute of Radio Measurement Dept. of Space Situational Awareness and Measurement Radar Beijing China

ISBN: (纸本)9781665498142

The composite waveform of multi-carrier phase coded and frequency modulation signal is an effective method to solve the integration of radar sensing and wireless communication. This paper mainly discussed three different types of waveforms: multi-carrier phase coded signal (MCPC), linear frequency modulation (LFM) in phase coded waveform, complex modulation of multi-carrier phase coded and frequency modulation Signal. In order to suppress radar interference and various clutter, a novel complex modulation waveform of MCPC and LFM using orthogonal frequency division multiplexing (OFDM) is designed. Signal models, formula expression and time-frequency characteristics are analyzed comprehensively for all of the conventional and novel waveforms. Numerical simulations and practical applications show that it can achieve good performance for anti-jamming and clutter suppression in the field of radar and communication by using the proposed complex modulation waveform. © 2021 IEEE.

关键词： frequency coding frequency modulation (FM) multi-carrier phase coded (MCPC) signal orthogonal frequency division multiplexing (OFDM) phase coded modulation (PCM)

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Information-theoretic properties of selected stochastic neuronal models

Information-theoretic properties of selected stochastic neur...

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作者： Bárta, Tomáš Charles University of Prague

According to the classical efficient-coding hypothesis, biological neurons are naturally adapted to transmit and process information about the stimulus in an optimal way. Shannons information theory provides methods to compute the fundamental limits on maximal information transfer by a general system. Understanding how these limits differ between different classes of neurons may help us to better understand how sensory and other information is processed in the brain. In this work we provide a brief review of information theory and its use in computational neuroscience. We use mathematical models of neuronal cells with stochastic input that realistically reproduce different activity patterns observed in real cortical neurons. By employing the neuronal input-output pro- perties we calculate several key information-theoretic characteristics, including the information capacity. In order to determine the information capacity we propose an iterative extension of the Blahut-Arimoto algorithm that generalizes to continuous input channels subjected to constraints. Finally, we compare the information optimality conditions among different models and parameter sets. 1

关键词： information capacity neuronal model frequency coding

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Enhancing the Radar Cross-Range Resolution in Ultra-Fast Radar Scans by Utilizing frequency Coded Sub-Channels

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SENSORS 2022年第9期22卷 3343-3343页

作者： Baer, Christoph Karsch, Nicholas Kaesbach, Robin Musch, Thomas Ruhr Univ Bochum Inst Elect Circuits Univ Str 150 D-44801 Bochum Germany

This contribution handles a single-channel radar method that utilizes frequency-coded sub-channels for enabling cross-range resolution. Because of the sub-channel coding, the whole area of interest (AOI) is scanned within a single radar measurement. To further enhance the cross-range resolution, the sub-channels' antenna beams are overlaid in this work, resulting in multiple coding signatures. Next to the operation theory, hardware components, such as coding filters and antennas, as well as signal processing methods, are presented and discussed in detail. A final measurement campaign that investigates several radar scenarios reveals high detection properties and proves the applicability of the proposed radar method.

关键词： scanning radar radar resolution frequency coding FMCW

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A Novel Localization System in SAR-Demining Applications Using Invariant Radar Channel Fingerprints

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SENSORS 2022年第22期22卷 8688-8688页

作者： Karsch, Nicholas Schulte, Hendrik Musch, Thomas Baer, Christoph Ruhr Univ Bochum Fac Elect Engn & Informat Technol Inst Elect Circuits Univ Str 150 D-44801 Bochum Germany

In this paper, we present a novel two dimensional (2D) frequency-modulated continuous-wave (FMCW) localization method for handheld systems based on the extraction of distinguishable subchannel fingerprints. Compared with other concepts, only one subdivided radar source channel is needed in order to instantly map a one-dimensional measurement to higher-dimensional space coordinates. The additional information of the detected target is implemented with low-cost hardware component features, which exhibit distinguishable space-dependent fingerprint codes. Using the given a priori information of the hardware thus leads to a universally applicable extension for low-cost synthetic aperture radar (SAR)-demining purposes. In addition to the description of the system concept and its requirements, the signal processing steps and the hardware components are presented. Furthermore, the 2D localization accuracy of the system and the classification accuracy of the frequency-coded fingerprints are described in a defined test environment to proof the operational reliability of the realized setup, reaching a classification accuracy of 94.7% and an averaged localization error of 4.9 mm.

关键词： RF fingerprints channel identification frequency coding FMCW radar localization

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