- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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A High-Resolution 220-GHz Ultra-Wideband Fully Integrated ISAR Imaging System
摘要： In this paper, an ultra-wideband fully integrated imaging radar at sub-terahertz (sub-THz) frequencies is presented, which demonstrates a fine lateral resolution without using any focal lens/mirror. We have achieved a lateral resolution of 2 mm for an object at 23-cm distance as well as a range resolution of 2.7 mm. To achieve the decent range resolution, in a frequency modulation continuous wave radar configuration, a state-of-the-art chirp bandwidth (BW) of 62.4 GHz at a center frequency of 221.1 GHz is generated and efficiently radiated. We have presented a design technique for the optimal design of the passive embedding around the core transistor to maximize the tuning BW of the voltage controlled oscillator. At the receiver side, to maximize the intermediate frequency level, a subharmonic mixer is utilized, which is designed for the lowest conversion loss. Finally, to obtain the fine lateral resolution, we have implemented near-field beamforming algorithm based on the inverse synthetic aperture radar (ISAR) systems. The synthesized beamwidth is less than 0.5°; hence, high-resolution images are reconstructed. The system is fabricated in a 55-nm BiCMOS process. To the best of our knowledge, this is the first imaging radar at THz/sub-THz frequencies, which utilizes ISAR to achieve a high lateral resolution while the radar system is fully integrated.
关键词： ultra-wideband,Frequency modulation continuous wave (FMCW),remote sensing,THz,radar,sub-terahertz (sub-THz),oscillator,inverse synthetic aperture radar (ISAR),plane wave
更新于2025-09-23 15:21:21
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[IEEE 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Odessa, Ukraine (2018.9.4-2018.9.7)] 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Modeling of Random Ultrawideband Signals and Antenna for Their Radiation
摘要： Possible approaches to the modeling of random ultra-wideband signals are discussed. The perspectivity of using the apparatus of stochastic differential equations for solving this problem is underlined and the merits of this approach are noted. The requirements for ultra-wideband antennas are described and prototypes of such antennas are described.
关键词： ultra-wideband signal,ultrawideband antenna,random process
更新于2025-09-23 15:21:21
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[IEEE 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Odessa, Ukraine (2018.9.4-2018.9.7)] 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Features of Millimeter-Wave Ultra-Wideband Signals Application in Telecommunications
摘要： In the paper, the features of millimeter-wave ultra-wideband signals application, related to photon methods of generation and transmission of millimeter-wave signals, as well as the quasi-optical approach for modeling signal loss (amplification) are considered. It is proposed to use more accurate models of millimeter-wave ultra-wideband radio systems, which should correspond to the fundamental physical features of the propagation of millimeter waves, especially in urban conditions. It is shown that when calculating such systems it is necessary to take into account the noise associated with the method of generating millimeter waves.
关键词： energy budget,wireless communications,noise regime,ultra-wideband signal,millimeter-wave,radio-over-fiber
更新于2025-09-23 15:21:21
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[IEEE 2019 IEEE Asia-Pacific Microwave Conference (APMC) - Singapore, Singapore (2019.12.10-2019.12.13)] 2019 IEEE Asia-Pacific Microwave Conference (APMC) - An Ultra Wideband Vivaldi Antenna Array Based on Tightly Coupled Effect
摘要： An ultra wideband Vivaldi antenna array based on tightly coupled effect is proposed. The elements are arranged overlap to get an additional capacitive capacity to achieve impedance matching at low frequency. A sample of a 4×4 Vivaldi array was simulated, fabricated, and tested. The measured farfield waveform is basically agreed with simulated one. The designed antenna gets a bandwidth of 0.4GHz-4.2GHz.
关键词： impedance matching,tightly coupled effect,Ultra wideband,Vivaldi antenna array
更新于2025-09-23 15:21:01
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Wide-Angle, Ultra-Wideband ISAR Imaging of Vehicles and Drones
摘要： In-situ, wide-angle, and ultra-wideband inverse synthetic aperture radar (ISAR) imaging of vehicles and drones is demonstrated using a portable ultra-wideband radar. In order to form well-focused ISAR images, motion compensation is performed before applying the k-space imaging algorithm. While the same basic motion compensation methodology is applied to both types of targets, a more complex motion model is needed to better capture the ?ight path of the drone. The resulting ISAR images clearly show the geometrical outline of the targets and highlight locations of prominent backscattering. The ISAR images are also assessed against images generated through instrumented targets or laboratory measurements, and the image quality is shown to be comparable.
关键词： ultra-wideband,radar imaging,vehicles,radar measurements,drones,inverse synthetic aperture radar
更新于2025-09-23 15:21:01
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Design of 2 to 18?GHz balanced antipodal Vivaldi antennas using substrate-integrated lenses
摘要： Conventional balanced antipodal Vivaldi antennas (BAVAs) normally have deep ripple levels in E-plane mainlobe region and significant H-plane beamwidth variation over upper frequency band, which are drawbacks for ultra-wideband (UWB) applications. To overcome these issues, this paper introduces two types of lens configurations in front of BAVA. A gradient-index semi-cylindrical lens and a cylindrical lens are employed to improve ripples depth of E-plane mainlobe and broaden H-plane beamwidth, respectively. Both these lenses and BAVA are integrated on the same substrate and the desired refractive indexes of lenses are realized by a combination of a set of air-filled holes in the substrate. Prototypes of the modified BAVA with lenses (BAVA-Ls) are designed, fabricated, and experimentally investigated as well. Measured results show close agreement with simulation. The proposed BAVA-Ls exhibit promising performances such as smaller ripple levels in E-plane mainlobe, wider H-plane beamwidth, higher aperture efficiency, and excellent group delay, while maintaining good bandwidth characteristics over 2 to 18 GHz.
关键词： effective medium theory,dielectric lens,ultra-wideband (UWB),Balanced antipodal Vivaldi antenna (BAVA)
更新于2025-09-23 15:21:01
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A Simple WiMAX and RFID band Notched UWB Bandpass Filter and It's susceptibility Study
摘要： An ultra-wideband (UWB) bandpass filter (BPF) with a fractional bandwidth (FBW) of about 110%, transmission zero at the high frequency edge, and band notches at the worldwide interoperability for microwave access (WiMAX) and radio frequency identification (RFID) band is presented in this paper. The filter is based on single short-circuited stub, U-shaped defected ground structure (DGS) array, two U-shaped resonators and two stepped impedance resonators (SIRs). The filter is compact and exhibits a selective filtering characteristic equivalent to a 3-pole Chebyshev filter. The design procedure has been described and verified by full-wave electromagnetic (EM) simulation and measurement. The proposed filter has low insertion loss, sharp rejection, and excellent in and out band performance. Due to its applications in WiMAX and RFID systems, the filter may be subjected to high EM radiation from the antenna and nearby sources. Therefore, susceptibility study of such filter is very important. Hence, the susceptibility study of the band notched UWB bandpass filter has been carried out by subjecting the structure to an interference source.
关键词： Microstrip band pass filters (BPFs),notch band,transmission zero,ultra-wideband (UWB) filters
更新于2025-09-23 15:21:01
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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) - Lightweight Broadband Antennas for UAV based GPR Sensors
摘要： In this contribution two different types of broadband antennas namely a logarithmic-periodic dipole antenna (LPDA) and a transversal electromagnetic (TEM) horn antenna for ground penetrating synthetic aperture radar sensors are presented. These antennas are designed to be mounted on an unmanned aircraft vehicle (UAV). The antennas are evaluated in terms of their matching, radiation pattern pulse response and weight. Finally, an integration example of one of these antennas is shown on an UAV.
关键词： ultra wideband antennas,dispersion,unmanned aerial vehicles,Ground penetrating radar
更新于2025-09-23 15:21:01
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Compact and low insertion loss UWB ona??chip bandpass filter using coupled meandered line
摘要： For ultra-wideband (UWB) communication applications, a low-loss compact filter is proposed based on coupled lines using the GaAs integrated passive devices (IPD) technology in this letter. The multistage coupling lines are used to realize the ultra-wide passband with 100% fractional bandwidth. Two modified stubs loaded with shorted capacitors are introduced between coupled lines to produce a new transmission zero near the lower pass-band edge, resulting in better frequency selectivity performance. Moreover, stepped impedance resonator (SIR) structure is applied to the coupled lines to improve impedance matching performance within ultra-wide pass-band. As demonstrated, the proposed filter is fabricated as a chip with a compact size of 1.8 × 1.7 mm2, the insertion loss of the filter is less than 1.5 dB from 6 to 18 GHz with the return loss better than 13.5 dB. All simulated and measured frequency responses of the proposed filter are found to match well with each other, which further demonstrates the claimed superior performances of the proposed filter.
关键词： bandpass filter,coupled line,integrated passive devices technology,ultra-wideband
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE Research and Applications of Photonics in Defense Conference (RAPID) - Miramar Beach, FL, USA (2019.8.19-2019.8.21)] 2019 IEEE Research and Applications of Photonics in Defense Conference (RAPID) - InGaAs/InAsSb Strained Layer Superlattice Infrared Detectors
摘要： Recent telecommunication systems exploit the degrees of freedom of the radio propagation channel more and more. Deeper investigations of system performance require realistic channel models. For this purpose, a new MIMO UWB channel sounder is introduced. The novelty is its capacity to estimate simultaneously direction of arrival and departure in 3D, including polarization state information. The second novelty is a modified SIC algorithm which speeds up the search of the multipath properties of the propagation channel. An extensive measurement campaign is performed in different residential environments and statistical results are provided.
关键词： ultra wideband technology,Channel models,direction of arrival estimation,radio propagation
更新于2025-09-23 15:19:57