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oe1(光电查) - 科学论文

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  • [IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Feasibility Analysis Using Load Profile Modeling Scenarios of Achieving Peak Shaving Using Grid-Tied PV for a Small Utility in Boone, North Carolina

    摘要: The distributed Brillouin analysis of an 8.8-km-long fiber with a spatial resolution of 2 cm is presented. All 440 000 potential resolution points are addressed in the measurement. A 7-cm-long hot-spot, located toward the output end of the pump wave, is properly identified in the experiment. The experimental error in the estimate of the local values of the Brillouin frequency shift is ±3.5 MHz. The analysis is based on the simultaneous generation and analysis of Brillouin interaction in more than 2000 correlation peaks, induced by periodic phase modulation of the pump and signal waves. The Brillouin amplifications at individual peaks are resolved using radar-like coding of pump wave magnitude by a 10000 bit-long aperiodic sequence, and postdetection compression at the receiver end. Extensive numerical simulations of the Brillouin interactions over kilometers of fiber with centimeter resolution are reported as well. The results are at the state of the art for high-resolution distributed Brillouin sensors.

    关键词: All-optical signal processing,fiber-optic sensors,correlation-domain analysis,stimulated Brillouin scattering,distributed fiber sensors,sequence compression

    更新于2025-09-23 15:19:57

  • [IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Bistable Properties of Nonlinear Planar Metamaterials : (Invited)

    摘要: Objective: evaluating stride events can be valuable for understanding the changes in walking due to aging and neurological diseases. However, creating the time series necessary for this analysis can be cumbersome. In particular, finding heel contact and toe-off events which define the gait cycles accurately are difficult. Method: we proposed a method to extract stride cycle events from tri-axial accelerometry signals. We validated our method via data collected from 14 healthy controls, 10 participants with Parkinson’s disease, and 11 participants with peripheral neuropathy. All participants walked at self-selected comfortable and reduced speeds on a computer-controlled treadmill. Gait accelerometry signals were captured via a tri-axial accelerometer positioned over the L3 segment of the lumbar spine. Motion capture data were also collected and served as the comparison method. Results: our analysis of the accelerometry data showed that the proposed methodology was able to accurately extract heel and toe-contact events from both feet. We used t-tests, analysis of variance (ANOVA) and mixed models to summarize results and make comparisons. Mean gait cycle intervals were the same as those derived from motion capture, and cycle-to-cycle variability measures were within 1.5%. Subject group differences could be similarly identified using measures with the two methods. Conclusions: a simple tri-axial acceleromter accompanied by a signal processing algorithm can be used to capture stride events. Clinical impact: the proposed algorithm enables the assessment of stride events during treadmill walking, and is the first step toward the assessment of stride events using tri-axial accelerometers in real-life settings.

    关键词: signal processing,gait,stride intervals,Gait accelerometry signals

    更新于2025-09-23 15:19:57

  • [IEEE 2018 IEEE International Ultrasonics Symposium (IUS) - Kobe, Japan (2018.10.22-2018.10.25)] 2018 IEEE International Ultrasonics Symposium (IUS) - A Compressed Sensing Based Miniaturized Photoacoustic Imaging System

    摘要: Compressed Sensing Based Photoelectric Imaging System

    关键词: Photoelectric Imaging,Image Reconstruction,Signal Processing,Compressed Sensing

    更新于2025-09-19 17:15:36

  • Shaping pulses of radiation detectors into a true Gaussian form

    摘要: A digital shaper for conversion of detector pulses with a short leading edge and a long exponential tail into a true Gaussian form is proposed and analysed in this paper. The width of Gaussian pulses can be several times smaller than the rise time of the input pulses, i.e. considerably shorter than the undistorted output pulses provided by standard shapers. The algorithm of the true Gaussian shaper is presented in the paper. The output pulses and noises of the true Gaussian shapers are compared with those of standard shapers for different widths of shaped pulses. The analyses has shown that the true Gaussian shaping can be advantageous for detection of strongly overlapped pulses which appear at high particle fluxes in the detector input.

    关键词: Digital signal processing (DSP),Electronic detector readout concepts (solid-state),Solid state detectors,Nuclear instruments and methods for hot plasma diagnostics

    更新于2025-09-19 17:15:36

  • High-Performance Time-Interleaved Optical Sampling Based on Temporal Lenticular Lens

    摘要: Optical sampling based on temporal lenticular lens can eliminate the requirement of high-power laser pulses and the need of wavelength conversion. In this work, we improve the spectrally efficient sampling scheme to process wideband optical signals applicable for communications. A parallel architecture based on time-interleaved sampling is demonstrated to increase the effective sampling rate. A 20-Gb/s signal is experimentally sampled and recovered at 80 GSample/s. The sampling system performance is measured and analyzed. Input optical frequencies from 40 to 80 GHz are characterized with an effective number of bits ranging from 4.2 to 3.5.

    关键词: fiber devices,optical sampling,optical signal processing

    更新于2025-09-19 17:15:36

  • [IEEE 2018 28th International Telecommunication Networks and Applications Conference (ITNAC) - Sydney, Australia (2018.11.21-2018.11.23)] 2018 28th International Telecommunication Networks and Applications Conference (ITNAC) - Advances in microwave photonic signal processing for 5G and IoT Keynote Paper

    摘要: Advances in microwave photonic signal processing for 5G and IoT are presented. Photonic signal processing offers a new powerful paradigm for processing high speed signals, due to its inherent advantages of wide bandwidth and immunity to electromagnetic interference. Recent trends are focused on realising photonic integrated circuits using silicon photonics that are compatible with CMOS electronics. Microwave photonic advances including versatile beamforming for phased array antennas, dispersion-free microwave-optical links, frequency conversion and filtering, and integrated high-resolution photonic sensors, are presented.

    关键词: microwave photonics,photonic signal processing

    更新于2025-09-19 17:15:36

  • Dynamic and quasi-static signal separation method for bridges under moving loads based on long-gauge FBG strain monitoring

    摘要: Structural health monitoring is an important means of obtaining the state information of bridges, and the extracted quasi-static strain signal can reflect the stress state of bridges directly. However, the strain signals acquired during the operation stage of bridges are dynamic, and the strain gauges used in the health monitoring system are short (no more than 10 cm), which means they are easily affected by small damage at the installation parts of bridges and thereby the monitoring signal abnormalities occur. A type of externally affixed long-gauge fiber strain gauge is used to monitor the health of bridges, and the dynamic and quasi-static signal separation method for long-gauge strain sensors is studied under different vehicle loads; at the same time, the dynamic monitoring performance of the long-gauge sensor is investigated in this paper. The quasi-static strain signal extracted from the dynamic macro-strain signal can be used to directly monitor the stress status of the bridge. The results show that the method proposed in this paper is feasible for extracting the quasi-static macro-strain from a dynamic long-gauge strain signal.

    关键词: signal processing,bridge engineering,empirical mode decomposition method,macro-strain,Bridge health monitoring

    更新于2025-09-19 17:15:36

  • [IEEE 2019 IEEE Globecom Workshops (GC Wkshps) - Waikoloa, HI, USA (2019.12.9-2019.12.13)] 2019 IEEE Globecom Workshops (GC Wkshps) - Free Space Optical Communication on UAV-Assisted Backhaul Networks: Optimization for Service Time

    摘要: Distance functions are at the core of important data analysis and processing tools, e.g., PCA, classification, vector median filter, and mathematical morphology. Despite its key role, a distance function is often used without careful consideration of its underlying assumptions and mathematical construction. With the objective of identifying a suitable distance function for hyperspectral images so as to maintain the accuracy of hyperspectral image processing results, we compare existing distance functions and define a suitable set of selection criteria. Bearing in mind that the selection of distance functions is highly related to the actual definition of the spectrum, we also classify the existing distance functions based on how they inherently define a spectrum. Theoretical constraints and behavior, as well as numerical tests are proposed for the evaluation of distance functions. With regards to the evaluation criteria, Euclidean distance of cumulative spectrum (ECS) was found to be the most suitable distance function.

    关键词: multidimensional signal processing,Image processing

    更新于2025-09-19 17:13:59

  • Enhanced Optical Communications Through Joint Time-Frequency Multiplexing Strategies

    摘要: We present a power-efficient and reduced-complexity all-optical approach to generate high-bit rate superchannels, based on joint time-frequency multiplexing. Both optical orthogonal frequency division multiplexing (OFDM) and Nyquist-optical time division multiplexing (N-OTDM) signals are generated and processed using a wavelength-selective switch (WSS). We use the fractional Fourier transform (FrFT) to introduce the largest degree of flexibility in optical networking, and we experimentally demonstrate that the transmitted signal can be received either in parallel, as OFDM subcarriers, or in series, as an N-OTDM signal. Compared to conventional optical OFDM, we achieve peak to average power ratio (PAPR) flexible reduction; compared to N-OTDM, we introduce chromatic dispersion (CD) management. We successfully demonstrate a field trial experiment of 4-channel 40 Gb/s hybrid OFDM/N-OTDM transmission over the 89.2-km Japan gigabit network-extreme (JGN X) test bed, with 1 bit/s/Hz spectral efficiency.

    关键词: optical Fourier transform,optical signal processing,Nyquist OTDM,OFDM,fractional Fourier transform

    更新于2025-09-19 17:13:59

  • [IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Shadow masking and tunnel contacts: A low cost process for high efficiency IBC solar cells

    摘要: One of the main vulnerabilities of GNSS receivers jamming is their exposure to intentional or unintentional signals, which could even cause service unavailability. Several alternatives to counteract these effects were proposed in the literature, being the most promising those based on multiple antenna architectures. This is specially the case for high-grade receivers used in applications requiring reliability and robustness. This article provides an overview of the possible receiver architectures encompassing antenna arrays and the associated signal processing techniques. Emphasis is also put on the most typical implementation issues found when dealing with such technology. A thorough survey is complemented with a set of experiments, including real data processing by a working prototype, which exemplifies the above ideas.

    关键词: array signal processing,Adaptive arrays,receiving antennas,satellite navigation systems,global positioning system,radio navigation,robustness,availability,electromagnetic interference

    更新于2025-09-19 17:13:59