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- 实验方案
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UWB Dual-polarized Dipole Array with Dielectric and FSS Superstrate and 65o Scanning
摘要： We report the design of an ultra‐wideband, dual‐polarized, tightly coupled dipole array (TCDA) with an integrated balun for wide angle scanning. A dual‐pol dipole design enables massive bandwidth, large scanning volume, and high polarization purity, concurrently. To achieve wide angle impedance matching without exciting surface waves, two types of superstrates are evaluated on a finite array: 1) dielectric superstrate and 2) novel planar frequency selective surface (FSS). The latter architecture is capable of scanning 70° in E Plane and 65° in H Plane and shows, on average, 5° scanning improvement to the former. The impedance bandwidth is 5.25:1 (0.8‐4.2 GHz) at the broadside (VSWR<2). The bandwidth reduces to 4.3:1 (0.9‐3.9 GHz) when maximum scanning angle or θmax increases to 65° for the H plane and 70° for the E plane (VSWR < 3.2). The proposed array is a great candidate for wide‐angle wide‐band scanning applications covering the entire L and S bands.
关键词： dielectric superstrate,FSS,wide angle scanning,TCDA,Ultra-wideband,frequency selective surface,dual-polarized,tightly coupled dipole array,integrated balun
更新于2025-09-10 09:29:36
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[IEEE 2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) - Honolulu, HI, USA (2018.7.18-2018.7.21)] 2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) - Classification of Human Posture from Radar Returns Using Ultra-Wideband Radar
摘要： There is a great need for new technology that helps ensure the well-being of senior citizens who have compromised health and are at an elevated risk of injury due to falls. Being able to detect posture and postural changes may be helpful in prediction and prevention of impending falls. Ultra-Wideband (UWB) radar is an attractive means for patient monitoring because it is inexpensive, capable of penetrating obstacles, privacy preserving and it consumes little power. In this paper, classification of postures, namely sitting, standing and lying is presented using stand-off sensing using UWB radar in an indoor environment. It is found that using location specific classifiers, overall accuracy can be improved. In this paper, a decision tree classifier capable of achieving 85% overall accuracy is proposed. This classifier uses 33 features from 10 second data sample segments.
关键词： posture classification,fall prediction,non-contact sensing,Ultra-Wideband radar,senior care
更新于2025-09-10 09:29:36
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DESIGN ANALYSIS AND MODELING OF DIRECTIONAL UWB ANTENNA WITH ELLIPTICAL SLOTTED GROUND STRUCTURE FOR APPLICATIONS IN C- & X-BANDS
摘要： A modi?ed technique to design directional ultra-wideband (UWB) antenna with slotted ground structure approach on the ground plane has been presented for applications in C- and X-bands. Initially, elliptical slot is inserted into ground and thereafter, the axis of ellipse is rotated 45 degrees in direction of the substrate. Minor axis of the ellipse is optimized to locate it symmetrically around the circular patch in order to obtain the full C- and X-band operations and also to enhance directivity. Thereafter, for further improvement in the directivity as well as gain, an elliptical slot in circular patch has also been introduced. The impedance bandwidth approximates about 95% covering the frequency ranging from 4.18–11.50 GHz. The return losses (S11) are ?38 dB and ?43 dB through simulation, which are ?24 dB and ?32 dB by measurement at 6.3 GHz, 9.3 GHz resonant frequencies, respectively. Simulated gain and half power beam width (HPBW) are 2.5–8.4 dB and 49–22 degrees in 4.18–11.50 GHz band, respectively. Gain and half power beam width (HPBW) of the proposed antenna improves by 1–2 dB and 5–10 degrees, respectively compared with previously designed antennas. Simulation of the antenna has been carried out on Computer Simulation Technology (CST) software on an FR-4 substrate having dielectric constant 4.3 of thickness 1.6 mm. The measured results show good agreement with equivalent circuit model and CST simulation.
关键词： C- and X-bands,impedance bandwidth,elliptical slot,directional ultra-wideband (UWB) antenna,slotted ground structure,directivity,gain
更新于2025-09-09 09:28:46
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[IEEE 2018 IEEE International Conference on Electro/Information Technology (EIT) - Rochester, MI (2018.5.3-2018.5.5)] 2018 IEEE International Conference on Electro/Information Technology (EIT) - Evaluation of Indoor Positioning Technologies for Prototyping at Kettering University
摘要： This paper presents research performed on indoor positioning technologies to identify a technology that would be best to implement in a prototype at Kettering University’s campus. The indoor positioning techniques evaluated are mainly based including Bluetooth, Wi-Fi, Geomagnetic, Visual Light Communication (VLC), and Ultra- Wideband (UW). Target-side wearable sensors will be considered. The algorithms commonly used for calculating the user’s position will be discussed, including Trilateration, Fingerprinting, and K- Nearest-Neighbor.
关键词： Visual Light Communication,Ultra-Wideband,Geomagnetic,Trilateration,K-nearest-neighbor,Fingerprinting,Indoor Positioning System,Wi-Fi,Bluetooth
更新于2025-09-09 09:28:46
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[IEEE 2018 International Conference on Advances in Computing, Communications and Informatics (ICACCI) - Bangalore, India (2018.9.19-2018.9.22)] 2018 International Conference on Advances in Computing, Communications and Informatics (ICACCI) - A Modified Frequency Selective Surface Band-stop Filter for Ultra-wideband Applications
摘要： A modi?ed design of a single-layer ultra-wideband (UWB) Frequency Selective Surface (FSS) re?ector is presented for microwave applications. The proposed FSS unit cell consists of a square-loop and a ring printed on opposite sides of a low-cost FR-4 substrate. With the optimized dimensions of the elements, the proposed FSS design provides a stop-bandwidth of 11.94 GHz (5.24-17.18 GHz). It is observed from simulation results that the proposed FSS design has a linear decreasing phase response in the desired band. Furthermore, the presented design provides a stable frequency response up to 450 oblique angle of incidence for both perpendicular (TE) and parallel (TM) polarizations.
关键词： Oblique incidence,Single-layer,FSS re?ector,Ultra-wideband
更新于2025-09-09 09:28:46
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Ultra-wideband and Polarization-Insensitive Perfect Absorber Using Multilayer Metamaterials, Lumped Resistors, and Strong Coupling Effects
摘要： We theoretically and experimentally proposed a new structure of ultra-wideband and thin perfect metamaterial absorber loaded with lumped resistances. The thin absorber was composed of four dielectric layers, the metallic double split ring resonators (MDSRR) microstructures and a set of lumped resistors. The mechanism of the ultra-wideband absorption was analyzed and parametric study was also carried out to achieve ultra-wideband operation. The features of ultra-wideband, polarization-insensitivity, and angle-immune absorption were systematically characterized by the angular absorption spectrum, the near electric-field, the surface current distributions and dielectric and ohmic losses. Numerical results show that the proposed metamaterial absorber achieved perfect absorption with absorptivity larger than 80% at the normal incidences within 4.52~25.42 GHz (an absolute bandwidth of 20.9GHz), corresponding to a fractional bandwidth of 139.6%. For verification, a thin metamaterial absorber was implemented using the common printed circuit board method and then measured in a microwave anechoic chamber. Numerical and experimental results agreed well with each other and verified the desired polarization-insensitive ultra-wideband perfect absorption.
关键词： Ultra-wideband,Polarization,Metamaterial absorbers,Subwavelength structures
更新于2025-09-09 09:28:46
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Performance evaluation of IR-UWB detectors and fusion techniques for UWB transceiver platforms
摘要： In this paper, we analyse the performance of a multi-pulse impulse radio based ultra-wideband (IR-UWB) detector in an AWGN setting and provide different fusion strategies for fusing these detector outputs. To enable the transceiver to be used for multiple applications, the designers have different types of detectors such as energy detectors, amplitude detectors, etc., built in to a single transceiver architecture. In this paper, we derive the detection performance equation for commonly used detectors in terms of false alarm rate, shape of the pulse, and number of UWB pulses used in the detection and apply these in the fusion algorithms. We show that the performance can be improved by approximately 4 dB in terms of signal to noise ratio (SNR) for high probability of detection of a UWB signal (95%), by fusing decisions from multiple detector types compared to a standalone energy detector, in a practical scenario.
关键词： UWB ranging,TOA,sensor networks,time of arrival,UWB,ultra wideband,Neyman-Pearson test
更新于2025-09-09 09:28:46
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[IEEE 2018 15th European Radar Conference (EuRAD) - Madrid, Spain (2018.9.26-2018.9.28)] 2018 15th European Radar Conference (EuRAD) - Detection of People Trapped under the Ruins Using Dual-frequency IR-UWB Radar
摘要： Detection of people hidden by obstacles using impulse radio ultra wideband radar has become a keen research nowadays. According to theories of the UWB radar, the lower center frequency is, the better penetrability radar has. And the larger bandwidth is, the higher radar range resolution becomes. In order to detect survivors trapped under the ruins of collapsed buildings, researches commonly focus on the radar with center frequency below 500 MHz. However, the radar with low center frequency always has small bandwidth, so it is relatively insensitive to the weak signal of the survivor. And this may lead to miss detection in search and rescue missions. Therefore, a novel dual-frequency IR-UWB radar system is developed in this paper. It can works alternately at each waveform with two center frequencies, which are 270 MHz and 400MHz. And the equivalent bandwidth of the system is relatively extended to enhance the sensitivity to weak vital signals. Moreover, cross-correlation technique is applied to the processed data of the two channels to improve the detected signal to noise ratio (SNR). The experimental results show that this system can both meet the need of low center frequency and large bandwidth in life detection and the detected SNR of the system is much higher than that of the single-frequency IR-UWB radar. So this system can work more reliably and effectively in the detection of people trapped under the ruins.
关键词： search and rescue (SAR),impulse radio ultra wideband (IR-UWB),cross-correlation,dual-frequency,life detection
更新于2025-09-09 09:28:46
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[IEEE 2018 IEEE Radio and Antenna Days of the Indian Ocean (RADIO) - Mauritius (2018.10.15-2018.10.18)] 2018 IEEE Radio and Antenna Days of the Indian Ocean (RADIO) - Circular SRR Shaped UWB Antenna with WiMAX Band Notch Characteristics
摘要： A Compact ultra-wideband microstrip patch antenna with single notch characteristics is proposed in this paper. The proposed antenna comprises of a split ring resonator (SRR) and an open loop rectangular resonator (OLRR). The split ring resonator in this paper plays a dual role, it acts as a radiating patch and also as a band rejecter to eliminate the entire worldwide interoperability for microwave access (WiMAX) covers 3.3 GHz – 3.6 GHz band. OLRR is used for the suppression of the harmonic frequency band notch. The compact size of the antenna is 36 × 30 mm2.
关键词： Split Ring Resonator (SRR),WiMAX band notch,Open Loop Rectangular Resonator (OLRR),Ultra-wideband (UWB)
更新于2025-09-04 15:30:14
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A high gain 60 GHz antipodal Fermi-tapered slot antenna based on robust synthesized dielectric
摘要： A high performance antipodal Fermi taper slot antenna based on unique synthesized dielectric is presented for ultra-wideband radar applications at 60 GHz band. Specifically, the synthesized dielectric is implemented based on machined holes concentrates only at aperture area to improve its mechanical robustness for lengthy antenna. Further, it is able to suppress back lobe level by 2.5 dB through curving tapered end of the antenna. Concurrently, sine corrugations and dielectric loading are adopted to improve radiation pattern and gain of the antenna for over 20 dB.
关键词： corrugation,dielectric,beamforming,ultra-wideband,tapered slot antenna
更新于2025-09-04 15:30:14