- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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HLS Based Approach to Develop an Implementable HDR Algorithm
摘要： Hardware suitability of an algorithm can only be verified when the algorithm is actually implemented in the hardware. By hardware, we indicate system on chip (SoC) where both processor and field-programmable gate array (FPGA) are available. Our goal is to develop a simple algorithm that can be implemented on hardware where high-level synthesis (HLS) will reduce the tiresome work of manual hardware description language (HDL) optimization. We propose an algorithm to achieve high dynamic range (HDR) image from a single low dynamic range (LDR) image. We use highlight removal technique for this purpose. Our target is to develop parameter free simple algorithm that can be easily implemented on hardware. For this purpose, we use statistical information of the image. While software development is verified with state of the art, the HLS approach confirms that the proposed algorithm is implementable to hardware. The performance of the algorithm is measured using four no-reference metrics. According to the measurement of the structural similarity (SSIM) index metric and peak signal-to-noise ratio (PSNR), hardware simulated output is at least 98.87 percent and 39.90 dB similar to the software simulated output. Our approach is novel and effective in the development of hardware implementable HDR algorithm from a single LDR image using the HLS tool.
关键词： system on chip,high-dynamic range image,low-dynamic range image,field-programmable gate array,high-level synthesis
更新于2025-09-23 15:22:29
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Analogue Wireless Beamforming Exploiting the Fiber-Nonlinearity of Radio Over Fiber Based C-RANs
摘要： As a key technique of supporting the fixed backbone network, radio over fiber (RoF) systems transmit the radio frequency signals over optical fiber in order to take advantage of their large available bandwidth. In this context, optical fiber aided phased antenna array (PAA) based beamforming techniques have attracted substantial research interest with the goal of improving the cell-edge coverage of cellular base stations. In this paper, we conceive a novel optical fiber aided beamforming technique based on the fiber's nonlinearity to be applied in cloud radio access network (C-RAN). In our proposed technique, the PAA elements are fed by the phase-shifted signals introduced by our highly nonlinear fiber (HNLF) aided phase-shifting solution, which results in an angular beamsteering range of around 90°. This can be exploited by sectorization in cellular networks to reduce the cochannel interference imposed. Furthermore, we exploit the proposed RoF-aided phase shifting technique in C-RAN, where our proposed system takes advantage of the centralized signal processing capability of the RoF system to conceive an all-optical processing based tunable beamforming system. While our flexible HNLF-aided phase-shifting process is confined to the central office of the C-RAN, the end users in the C-RAN cellular networks are capable of flexibly choosing the serving remote radio heads (RRHs) and employing diverse wireless transmission techniques. Through integrating our HNLF-aided phase-shifting design into the proposed C-RAN, we impose as little as 0.1 dB signal-to-noise Ratio (SNR) degradation compared to its traditional electronic counterpart, which requires extra phase-shifters.
关键词： phase-shifter,self-phase modulation,phased array antenna beamforming,C-RAN,cross-phase modulation,highly nonlinear fiber,Optical fiber,optical nonlinearity
更新于2025-09-23 15:22:29
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Epidermis inspired ultrathin 3D cellular sensors array for self-powered biomedical monitoring
摘要： Sensing devices with wearability would open the door to many advanced applications including soft robotics, artificial intelligence and healthcare monitoring. Here, inspired by the configuration of human epidermis, we present a flexible three-dimensional (3D) cellular sensor array (CSA) via a one-step thermally induced phase separation method. The CSA was framed by 3D cellular electret with caged piezoelectric nanoparticles, which was ultrathin (80 μm), lightweight and high mechanically durable. For biomedical sensing, the 3D-CSA holds a decent pressure sensitivity up to 0.19 V kPa-1 with a response time of less than 16 ms. Owing to its rigid structural symmetry, the 3D-CSA could be identically operated from both sides, and it was demonstrated to successfully measure the human heartbeat, detect the eye ball motion for sleeping quality monitoring, as well as tactile image. Mimicking the functionalities of human skin with a self-powered operation feature, the 3D-CSA was expected to represent a substantial advancement in wearable electronics for healthcare.
关键词： ultrathin,biomedical monitoring,self-powered,cellular sensors array,epidermis
更新于2025-09-23 15:21:21
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[IEEE 2018 International Conference on Electromagnetics in Advanced Applications (ICEAA) - Cartagena des Indias, Colombia (2018.9.10-2018.9.14)] 2018 International Conference on Electromagnetics in Advanced Applications (ICEAA) - Antenna Integrated With a Microstrip Filter for 5G Mm-wave Applications
摘要： In this work, a filtering mm-wave antenna array is proposed for the future 5G mobile devices. The filtering antenna design is based on the fourth-order coupled line planar filter with a metal lid added in order to increase the filter sharpness and decrease loss. In this paper, the metal lid is modified so the slot antenna is formed at the end of the filter. Finally, the proposed antenna element is combined into a linear phased array on the short edge of the typical mobile ground plane.
关键词： mm-wave,antenna array,filtering antenna,mobile devices,5G
更新于2025-09-23 15:21:21
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Adaptive AoA and Polarization Estimation for Receiving Polarized mmWave Signals
摘要： This paper proposes a novel hybrid dual-polarized antenna array which exploits two orthogonally-collocated dipoles to capture the full power of a polarized millimeter wave signal. To maximize the received signal-to-noise ratio (SNR), we study the adaptive angle-of-arrival and polarization state estimation, and develop a differential beam tracking algorithm and a cross-correlation-to-power ratio polarization tracking algorithm for interleaved hybrid dual-polarized arrays. Simulation results verify the superior performance of the proposed algorithms, and confirm the significant improvement of SNR obtained by using the proposed array and algorithms.
关键词： angle-of-arrival estimation,Hybrid dual-polarized antenna array,polarization state estimation,mmWave
更新于2025-09-23 15:21:21
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A Low-cost Ka-band Circularly Polarized Passive Phased-Array Antenna for Mobile Satellite Applications
摘要： This paper presents a low-profile, high-performance, and low-cost Ka-band circularly polarized (CP) passive phased-array antenna (PAA) system. A 1 × 4 passive sub-array operating at the Ka-band frequency band is investigated, developed, and tested as a possible building block for mobile satellite communication systems. In particular, a CP antenna integrated with a high-performance passive phase shifter is presented and experimentally verified. A new low-cost and low-profile magnetic actuator is proposed to precisely control the phase state of the phase shifter. A 3-D printed polymer package is utilized to enclose the phase shifter and reduce the environmental effects. The proposed CP passive PAA achieves high performance right hand circularly polarized (RHCP) radiation with high cross-polarization discrimination over a wide scan angle from 0o to ±38o over the frequency band (29.5-30.5 GHz). An AR < 3dB is demonstrated over the entire scanning range. Moreover, the measured radiation efficiency is 60% at bore-sight. The gain drops by 1 dB at ±38o scanning angles.
关键词： satellite mobile communication,millimeter-wave phased-array antenna,phase shifter,Circularly polarized antenna
更新于2025-09-23 15:21:21
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Annular Array 3-D Sar: Resolution Analysis and Data Processing
摘要： Array synthetic aperture radar (SAR) is one of the hot areas in radar imaging field because of its three-dimensional (3-D) imaging ability. Combining the advantages of linear array SAR in aspect of side-lobe suppression and circular SAR in aspect of high resolution, a new kind of annular array synthetic aperture radar (AASAR) mode is employed for 3-D microwave imaging. Based on the mathematical derivation of AASAR model, the sparse layout of the annular array in the cross-track direction can acquire 3-D high resolution and effective side-lobe suppression ability. Then on this basis, a proto-type AASAR experiment system is built, and some 3-D AASAR imaging outdoor experiments are conducted. Through the experiment result, the validity of 3-D AASAR imaging can be demonstrated.
关键词： 3-D imaging,annular array,high resolution,side-lobe suppression,Synthetic aperture radar
更新于2025-09-23 15:21:21
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SYNTHESIS OF THINNED ARRAY WITH SIDE LOBE LEVELS REDUCTION USING IMPROVED BINARY INVASIVE WEED OPTIMIZATION
摘要： As a very powerful optimization algorithm, invasive weed optimization has been widely applied to continuous optimization problems in electromagnetic (EM) field. However, the optimization of a thinned array can be formulated as a discrete-variable optimization problem with solutions encoded as binary strings. Therefore, in this paper, an improved binary invasive weed optimization (IBIWO) is proposed to design a thinned array with minimum side lobe levels. To evaluate the performance of the proposed algorithm, two examples have been presented and solved. Simulation results of the proposed thinned arrays obtained by IBIWO are compared with published results to verify the effectiveness of the proposed method.
关键词： binary invasive weed optimization,side lobe levels reduction,IBIWO,thinned array
更新于2025-09-23 15:21:21
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Datacubes: A Technology Survey
摘要： Datacubes are emerging as a paradigm which allows offering massive spatio-temporal data more in a more homogenized and better to analyze fashion, in particular when it comes to mixed spatial and temporal evaluation. While this is agreed by many, there is no broad consensus yet on access APIs and paradigms, such as query languages versus procedural inter-faces. Further, questions of efficient storage organization and processing of the underlying multi-dimensional arrays arise. In our contribution we provide a technology overview on datacube approaches, involving Array Databases, systems with procedural (typically python) interfaces, array libraries, and more.
关键词： Datacube,Array Database,Analysis Ready Data,Survey
更新于2025-09-23 15:21:21
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Adaption of an array spectroradiometer for total ozone column retrieval using direct solar irradiance measurements in the UV spectral range
摘要： A compact array spectroradiometer that enables precise and robust measurements of solar UV spectral direct irradiance is presented. We show that this instrument can retrieve total ozone column (TOC) accurately. The internal stray light, which is often the limiting factor for measurements in the UV spectral range and increases the uncertainty for TOC analysis, is physically reduced so that no other stray-light reduction methods, such as mathematical corrections, are necessary. The instrument has been extensively characterised at the Physikalisch-Technische Bundesanstalt (PTB) in Germany. During an international total ozone measurement intercomparison at the Iza?a Atmospheric Observatory in Tenerife, the high-quality applicability of the instrument was verified with measurements of the direct solar irradiance and subsequent TOC evaluations based on the spectral data measured between 12 and 30 September 2016. The results showed deviations of the TOC of less than 1.5 % from most other instruments in most situations and not exceeding 3 % from established TOC measurement systems such as Dobson or Brewer.
关键词： stray-light reduction,direct solar irradiance measurements,array spectroradiometer,total ozone column,UV spectral range
更新于2025-09-23 15:21:21