- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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A broadband circularly polarized monopole antenna
摘要： A compact modified C-shaped monopole antenna with broadband circular polarization is proposed, fabricated and measured. The antenna structure is simple and only consists of combined modified C-shaped radiation patch and an improved ground plane with the overall size of 25 × 25 × 1 mm3. By cutting the corner on the modified C-shaped patch and adding triangular stubs on the ground plane, the wide impedance bandwidth and axial ratio bandwidth are achieved. The design process of the antenna is given, and the circular polarization mechanism of the circularly polarized antenna is analyzed from the surface current distributions. The measured impedance bandwidth is 95.2% (4.4-12.4 GHz) with return loss better than 10 dB, and the measured 3 dB axial ratio bandwidth is 96.8% (4.42-12.72 GHz). The peak gain is above 3.0 dBi within the working band, which indicates that it is suitable for application of ultra-wideband (UWB) wireless communication systems and satellite communication systems.
关键词： axial ratio,ultra-wideband (UWB),monopole antenna,circular polarization
更新于2025-09-23 15:23:52
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[IEEE 2018 25th IEEE International Conference on Image Processing (ICIP) - Athens, Greece (2018.10.7-2018.10.10)] 2018 25th IEEE International Conference on Image Processing (ICIP) - Recovery of UWB Radar Signals in Spectrally Restricted Environments
摘要： This paper presents a novel technique to recover the missing spectral information due to RF spectral restriction in ultra-wideband (UWB) synthetic aperture radar (SAR) imaging. We address a critical problem in UWB radar imaging: radar transmission is prohibited in reserved frequency bands specified by local frequency management agencies. We model the problem in a compressed sensing setup where a time-sparse received radar signal at each aperture is collected in the incoherent frequency domain using a stepped-frequency implementation. Using electromagnetic (EM) finite-difference, time-domain (FDTD) data of various targets and clutter objects computed at all viewing aspect angles, we show that the proposed technique can successfully recover the relevant information on targets of interest even from a large percentage of missing frequency bands.
关键词： step-frequency,sparse recovery,synthetic aperture radar,spectral restriction,Ultra-wideband
更新于2025-09-23 15:23:52
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A Novel Miniaturized Planar Ultra-Wideband Antenna
摘要： A novel miniaturized planar ultra-wideband antenna is proposed. The antenna design comprises an electromagnetically coupled structure and a tapered radiating slot, while a triangular slot is etched on the ground plane. The antenna miniaturization is realized by adopting an electromagnetically coupled structure formed by the notched half-ellipse patch and the strip attached to the ground. The proposed antenna can yield a large 10-dB impedance bandwidth ranging from 1.5 to 10.4 GHz with satisfactory radiation properties. It also features a physical size of 37.4 mm × 64 mm, equivalent to a compact electrical size of 0.19λ × 0.32λ at 1.5 GHz. The important design parameters are analyzed to comprehend the operating principle of the antenna. A good agreement between the simulated and measured results is achieved.
关键词： compact antenna,Ultra-wideband antenna,planar antenna,antenna miniaturization
更新于2025-09-23 15:23:52
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Dual-Linear Polarized Phased Array with 9:1 Bandwidth and 60° Scanning off Broadside
摘要： We present for the first time a novel dual-linear polarized tightly coupled dipole array (TCDA) with integrated balun operating across a 9:1 bandwidth, from 2GHz to 18GHz. This dual-linear polarized array employs a tightly coupled dipole topology and scans down to 60° from boresight. The overall geometry consists of cross-located tightly coupled dipoles integrated with a folded Marchand balun that serves as an impedance transformer to achieve a wideband feeding network. Notably, the traditional dielectric superstrate is replaced with double layers of frequency selective surfaces (FSS) to enable scanning down to 60° in both E-, H-, and diagonal (D-) planes across the entire band. The design achieves VSWR<3 across 2 to 18GHz at broadside. This dual-polarized array is also demonstrated to have a good polarization isolation of -20dB for most of the band. The array’s total height is less than 12mm (λlow/10). The design is validated through fabrication and testing of an 11×11 prototype. Measurements of this prototype are presented and are in good agreement with simulations.
关键词： tightly coupled dipole array,low profile array,ultra-wideband,wide-angle scanning
更新于2025-09-23 15:22:29
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[IEEE 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Odessa (2018.9.4-2018.9.7)] 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Fractal Analysis of the Gravitational Waves as a Unique Ultra-Wideband Process
摘要： The results of the fractal analysis of the gravitational waves generated by a binary black hole merger and registered first on September 14, 2015 at 09:50:45 UTC by two detectors of the Laser Interferometer Gravitational-Wave Observatory (United States) are considered. Being a unique ultra-wideband natural process, the gravitational waves were appeared to be fractal one too. Their fractal structure is described by the set of numerical characteristics based on estimation of different fractal dimensions. The results obtained are widely discussed.
关键词： ultra-wideband process,gravitational wave,fractal analysis
更新于2025-09-23 15:22:29
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Lightweight Ultra-Wideband RCS Reduction Structure using Double-Layer Metasurfaces
摘要： In this paper, we propose the design of a lightweight RCS reduction structure using double-layer metasurfaces. The structure is composed of two layers of metasurfaces spaced by PMI foams. To extend the bandwidth, two unit structures are firstly designed to operating in two respective bands for circularly polarized (CP) waves, which are then combined to act as the unit structure of the double-layer metasurface. The metasurface is expected to operate in two continuous bands. Nevertheless, due to the couplings between the two unit structures, there is Fano resonance that prohibits merging of the two bands. To solve this problem, we tune the resonant frequency of the bottom unit structure to suppress the Fano resonance and obtain a merged band. The combined unit structure is employed as the element of chessboard configuration, which can reduce RCS by more than 10dB in an ultra-wideband (4.5-16.5GHz). We designed, fabricated and measured a lightweight prototype (the aerial density is 726g/m2). Both the simulation and experiment result verify the design. This work provides an effective method of extending the operation band of RCS reduction without sacrificing the efficiency.
关键词： metasurface,ultra-wideband,Fano resonance,RCS reduction
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE Photonics Conference (IPC) - Reston, VA (2018.9.30-2018.10.4)] 2018 IEEE Photonics Conference (IPC) - High-Power Photonic Phased Array Antennas
摘要： We review recent work on a new antenna concept— the high-power photonic phased array. By integrating high-power photodiodes proximal to the transmit aperture’s radiating elements, dense, lightweight, and broadband array designs are realized. Several manifestations of this idea are discussed, emphasizing different application-specific design choices.
关键词： RF photonics,ultra-wideband (UWB),photonic antenna,phased array antenna,5G,high-power photodiode,millimeter wave (mmW)
更新于2025-09-23 15:22:29
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[IEEE 2018 Wave Electronics and its Application in Information and Telecommunication Systems (WECONF) - Saint-Petersburg, Russia (2018.11.26-2018.11.30)] 2018 Wave Electronics and its Application in Information and Telecommunication Systems (WECONF) - Performance of UWB Signal Detecting Circuits
摘要： ultra-wideband (further UWB) signals are increasingly being used in communication systems. The paper presents three practical schemes for digital detectors of bursts of ultra-wideband signals and provides analytical expressions for calculating their performance.
关键词： ultra-wideband signals,quasi-optimal reception,digital detectors
更新于2025-09-23 15:22:29
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All-optical regenerative technique for width-tunable ultra-wideband signal generation
摘要： We demonstrate all-optical generation of width-tunable mono-cycle pulses for ultra-wideband communication. It has been shown that the width of the mono-cycle pulses can be tuned dynamically by simply varying the power of the optical signal. We also investigate the regenerative property of the nonlinear medium-based technique for the generation of mono-cycle pulses. For the purpose of comparison, ultra-wideband mono-cycle pulses are also generated through the optical delay line-based technique. It has been demonstrated through numerical simulations that the nonlinear medium-based technique is highly resilient to amplified spontaneous emission noise that is induced over the optical signal. Furthermore, we have shown that the highly nonlinear fiber-based nonlinear medium performs better than the semiconductor optical amplifier-based medium. Bit error rate measurements are taken for different values of optical signal-to-noise ratios in order to elaborate our work.
关键词： Gaussian mono-cycle pulses,Ultra-wideband over fiber,Semiconductor optical amplifier,Pulse width tuning,Highly nonlinear fiber
更新于2025-09-23 15:22:29
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Multi-fidelity EM simulations and constrained surrogate modelling for low-cost multi-objective design optimisation of antennas
摘要： In this study, a technique for low-cost multi-objective design optimisation of antenna structures has been proposed. The proposed approach is an enhancement of a recently reported surrogate-assisted technique exploiting variable-fidelity electromagnetic (EM) simulations and auxiliary kriging interpolation surrogate, the latter utilised to produce the initial approximation of the Pareto set. A bottleneck of the procedure for higher-dimensional design spaces is a large number of training data samples necessary to construct the surrogate. Here, the authors propose a procedure that allows us to confine the model domain to the subset spanned by the reference points, including the extreme Pareto-optimal designs obtained by optimising the individual objectives as well as an additional design that determines the Pareto front curvature. Setting up the surrogate in the constrained domain leads to a dramatic reduction of the required number of data samples, which results in lowering the overall cost of the optimisation process. Furthermore, the model domain confinement is generic, i.e. applicable for any number of design goals considered. The proposed technique is demonstrated using an ultra-wideband monopole antenna optimised with respect to three objectives. Significant reduction of the design cost is obtained as compared to the reference surrogate-assisted algorithm.
关键词： Pareto set,antenna structures,variable-fidelity EM simulations,kriging interpolation surrogate,multi-objective design optimisation,ultra-wideband monopole antenna
更新于2025-09-23 15:21:21