- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Single Flip-Chip Packaged Dielectric Resonator Antenna for CMOS Terahertz Antenna Array Gain Enhancement
摘要： A single dielectric resonator antenna (DRA) capable of enhancing the antenna gain of each element of a 2×2 THz antenna array realized in a 0.18-μm CMOS technology is proposed in this work. The DRA implemented in a low-cost integrated-passive-device (IPD) technology is flip-chip packaged onto the CMOS antenna array chip through low-loss gold bumps. By designing the DRA to work at the higher-order mode of TE3,δ,9, only single DRA instead of conventionally needing four DRAs is required to simultaneously improve the antenna gain of each element of the 2×2 antenna array. This not only simplifies the assembly process but it can also reduce the assembly cost. Moreover, the DRA can provide great antenna gain enhancement because of being made of high-resistivity silicon material and higher-order mode operation. The simulated antenna gain of each on-chip patch antenna of the 2×2 CMOS antenna array can be increased from 0.1 to 8.6 dBi at 339 GHz as the DRA is added. To characterize the proposed DRA, four identical power detectors (PDs) are designed and integrated with each element of the 2×2 THz antenna array, respectively. By measuring the voltage responsivity of each PD output, the characteristics of each antenna of the antenna array with the proposed DRA, including the gain enhancement level and radiation pattern, can be acquired. The measurement results follow well with the simulated ones, verifying the proposed DRA operation principle. The four PDs with the proposed DRA are also successfully employed to demonstrate a THz imaging system at 340 GHz. To the best of the authors’ knowledge, the proposed DRA is the one with the highest-order operation mode at THz frequencies reported thus far.
关键词： Silicon,Flip-chip packaging,Terahertz,CMOS,Terahertz imaging system,Antenna,Higher-order mode,Power detector,Dielectric resonator antenna
更新于2025-09-23 15:23:52
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Geometric Calibration of Markerless Optical Surgical Navigation System
摘要： Background: Patient-to-image registration is required for image-guided surgical navigation, but marker-based registration is time consuming and subject to manual error. Markerless registration is an alternative solution to avoid these issues. Methods: This study designs a calibration board and proposes a geometric calibration method to calibrate the near infrared tracking and structured light components of the proposed optical surgical navigation system simultaneously. Results: A planar board and a cylinder are used to evaluate the accuracy of calibration. The mean error for the board experiment is 0.035 mm, and the diameter error for the cylinder experiment is 0.119 mm. A calibration board is reconstructed to evaluate the accuracy of the calibration, and the measured mean error is 0.012 mm. A head phantom is reconstructed and tracked by the proposed optical surgical navigation system. The tracking error is less than 0.3 mm. Conclusions: Experimental results show that the proposed method obtains high accessibility and accuracy and satisfies application requirements.
关键词： Calibration,Markerless,Structure light,Optical surgical navigation system
更新于2025-09-23 15:23:52
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[IEEE 2018 26th European Signal Processing Conference (EUSIPCO) - Roma, Italy (2018.9.3-2018.9.7)] 2018 26th European Signal Processing Conference (EUSIPCO) - Spatio-Spectral Multichannel Reconstruction from few Low-Resolution Multispectral Data
摘要： This paper deals with the reconstruction of a 3-D spatio-spectral object observed by a multispectral imaging system, where the original object is blurred with a spectral-variant PSF (Point Spread Function) and integrated over few broad spectral bands. In order to tackle this ill-posed problem, we propose a linear forward model that accounts for direct (or auto) channels and between (or cross) channels degradation, by modeling the imaging system response and the spectral distribution of the object with a piecewise linear function. Reconstruction based on regularization method is proposed, by enforcing spatial and spectral smoothness of the object. We test our approach on simulated data of the Mid-InfraRed Instrument (MIRI) Imager of the James Webb Space Telescope (JWST). Results on simulated multispectral data show a significant improvement over the conventional multichannel method.
关键词： Deconvolution,Image reconstruction,Inverse problems,Multispectral restoration,System modeling
更新于2025-09-23 15:23:52
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[IEEE 2018 5th International Conference on Advanced Informatics: Concept Theory and Applications (ICAICTA) - Krabi (2018.8.14-2018.8.17)] 2018 5th International Conference on Advanced Informatics: Concept Theory and Applications (ICAICTA) - The Experimental Set of Light Distribution Analysis by LabView Application
摘要： This research presents experimental set of distribution light. Light illuminance is displayed by LabView application. The set was tested by four types of lamp (CFL), incandescent, E27 LED (Light Emitting Diode), T8 tubular fluorescent (FL). The 3 types of luminaire are used for testing. They consisted of down light, high bay and fluorescent reflector. The black close room was 1.5x1.5x1.5 m in size. It was constructed by steel and plywood. The center floor of the room is installed by LDR (Light Dependent Resistor). It was used for measuring the illuminance. LabView application was applied to display value on computer screen. The stepping motor was installed to rotate the lamp. It was controlled by LabView through DAQ 6008 interface card. It was rotated from -90o to 90o. The control set consisted of interface card, motor drive and power supply. They were contained in the insulation box outside of the test room. From the experimental result, the LDR illuminance meter can measure illuminance with 4.52% average error. The light distribution curve from experiment set is correspondent with theory.
关键词： LabView,LDR,illuminance,lighting system,light distribution
更新于2025-09-23 15:23:52
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[IEEE 2018 2nd International Conference on Trends in Electronics and Informatics (ICOEI) - Tirunelveli, India (2018.5.11-2018.5.12)] 2018 2nd International Conference on Trends in Electronics and Informatics (ICOEI) - Highly Efficient Constant Power Generation Using Solar Tree
摘要： In the solar system which is connected to the grid; it is essential to select reliable and efficient solar converter and inverter with higher efficiency. The electrical converter ought to management the injecting power to the inverter and the inverter ought to be in the position to control the injecting power to the grid. This paper discusses an efficient concept of solar power generation called as Solar Tree and also the ZVT-ZCT-PWM boost converter topology and HERIC inverter topology for highly efficient system. Also we have done a simulation for this system which has desirable results.
关键词： Solar Tree,PV system,ZVT-ZCT-PWM boost converter,HERIC inverter
更新于2025-09-23 15:23:52
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[IEEE 2018 International Conference on Power, Energy, Control and Transmission Systems (ICPECTS) - Chennai (2018.2.22-2018.2.23)] 2018 International Conference on Power, Energy, Control and Transmission Systems (ICPECTS) - Design and Hardware Implementation of Self Lift Negative Output Luo Converter Using MPPT for PV Applications
摘要： The design and analysis of self lift N/O luo converter is discussed in this paper. The incremental conductance mppt extracts the maximum power from PV panel and transfers to the load. The PV panel is designed by using equivalent circuit of PV cell. The output obtained from the solar panel contains more ripples. The ripples will produce more fluctuations. By using self lift negative output luo converter the unregulated output will be conveted into regulated voltage and stepped up to the higher voltage. For obtaining simulation results Matlab software is used.
关键词： Incremental conductance (IncCond) Maximum Power Point Tracking (MPPT) algorithm,self lift negative output luo converter,Photovoltaic system
更新于2025-09-23 15:23:52
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Multi-point Gaussian States, Quadratic–Exponential Cost Functionals, and Large Deviations Estimates for Linear Quantum Stochastic Systems
摘要： This paper is concerned with risk-sensitive performance analysis for linear quantum stochastic systems interacting with external bosonic fields. We consider a cost functional in the form of the exponential moment of the integral of a quadratic polynomial of the system variables over a bounded time interval. Such functionals are related to more conservative behaviour and robustness of systems with respect to statistical uncertainty, which makes the challenging problems of their computation and minimization practically important. To this end, we obtain an integro-differential equation for the time evolution of the quadratic–exponential functional, which is different from the original quantum risk-sensitive performance criterion employed previously for measurement-based quantum control and filtering problems. Using multi-point Gaussian quantum states for the past history of the system variables and their first four moments, we discuss a quartic approximation of the cost functional and its infinite-horizon asymptotic behaviour. The computation of the asymptotic growth rate of this approximation is reduced to solving two algebraic Lyapunov equations. Further approximations of the cost functional, based on higher-order cumulants and their growth rates, are applied to large deviations estimates in the form of upper bounds for tail distributions. We discuss an auxiliary classical Gaussian–Markov diffusion process in a complex Euclidean space which reproduces the quantum system variables at the level of covariances but has different fourth-order cumulants, thus showing that the risk-sensitive criteria are not reducible to quadratic–exponential moments of classical Gaussian processes. The results of the paper are illustrated by a numerical example and may find applications to coherent quantum risk-sensitive control problems, where the plant and controller form a fully quantum closed-loop system, and other settings with nonquadratic cost functionals.
关键词： Linear quantum stochastic system,Gaussian quantum state,Risk-sensitive quantum control
更新于2025-09-23 15:23:52
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Intelligent Indoor Mobile Robot Navigation Using Stereo Vision
摘要： Majority of the existing robot navigation systems, which facilitate the use of laser range finders, sonar sensors or artificial landmarks, has the ability to locate itself in an unknown environment and then build a map of the corresponding environment. Stereo vision,while still being a rapidly developing technique in the field of autonomous mobile robots, are currently less preferable due to its high implementation cost. This paper aims at describing an experimental approach for the building of a stereo vision system that helps the robots to avoid obstacles and navigate through indoor environments and at the same time remaining very much cost effective. This paper discusses the fusion techniques of stereo vision and ultrasound sensors which helps in the successful navigation through different types of complex environments. The data from the sensor enables the robot to create the two dimensional topological map of unknown environments and stereo vision systems models the three dimension model of the same environment.
关键词： Point clouds,Triangulation,SLAM,Arduino,Stereo vision system
更新于2025-09-23 15:23:52
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Underwater optical wireless sensor networks using resource allocation
摘要： Optical wireless communications is an energy efficient and cost-effective solution for high speed and high secure wireless connections. In this paper, we propose an underwater optical wireless sensor network using multiple input multiple output technique and power allocation algorithm for supporting multiple users with the impacts of underwater channel uncertainty interferences. In proposed power allocation algorithm, all the LED nodes in are coordinated and controlled by a central controller; each LED node supports all the users within its field of view. To separate users, optical code division multiple access is used; cyclic optical orthogonal code working as CDMA code is employed. At the receiver, a minimal mean squared error (MMSE) filter is uniquely designed for each user. The MMSE filters and the assigned power can be jointly optimized to improve the overall throughput and signal to noise ratio. Since the system performance may be impacted by the underwater channel uncertainty, the proposed power allocation can use the predicted channel uncertainty variance to reduce the interference of the channel uncertainty and improve the signal to noise ratio. Compared to the equal power allocation algorithm, the proposed algorithm can support longer transmission distance, higher bit rate and lower bit error rate.
关键词： Multiple access interference,Underwater communications,Wireless sensor networks,Channel uncertainty,MIMO system,CDMA,Optical wireless communications,Resource allocation
更新于2025-09-23 15:23:52
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Consideration of the Impact of the Environmental Conditions when Designing Heat-Receiving Systems of the Solar Cylindrical Parabolic Modules
摘要： The aerohydrodynamic and heat exchange characteristics in the cylindrical heat receiver of a solar cylindrical parabolic concentrating module are investigated. The mathematical model is based on the Navier-Stokes equation system for a laminar flow in a channel. The model is implemented using the control volume method. The created computer algorithm allows carrying out parametric studies and revealing the most rational geometric, dynamic, and power parameters of the process. The proposed model describes the general physical outlines of the heat exchange in a cylindrical heat receiver which allows estimating the influence of the environment—wind velocity, ambient temperature, etc.—on it.
关键词： cylindrical heat receiver,rational geometric, dynamic, and power parameters,solar cylindrical parabolic module,wind velocity,Navier-Stokes equation system,ambient temperature,control volume method
更新于2025-09-23 15:23:52