- 标题
- 摘要
- 关键词
- 实验方案
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New Class of RCS-Reduction Metasurfaces Based on Scattering Cancellation Using Array Theory
摘要： A technique to synthesize a new category of Radar Cross Section (RCS)-reduction metasurfaces is presented. The appealing feature of the proposed technique is that by representing the generalized Snell-Descartes’ law of reflection in the form of array factor, it unifies the two most widely studied and well established modern RCS-reduction methods: checkerboard metasurfaces (CMS) and gradient index metasurfaces (GIMS). More importantly, it refines the concepts of both of these metasurfaces and overcomes numerous limitations associated with them. It can synthesize the RCS-reduction metasurfaces which can be placed along with almost any existing metasurface, without replacing the original metasurface that may be designed to serve a specific purpose, to reduce its RCS. The proposed technique is fundamentally based on scattering cancellation, and it is validated using artificial magnetic conductor (AMC) technology for several configurations. Moreover, a phasor representation is developed and implemented for complex configurations to make the synthesis simpler and more insightful. Finally, to display the versatility of the proposed technique, an example of RCS-reduction metasurface has been synthesized and introduced to an existing high-gain metasurface ground plane available in the literature. This paper is confined to the conventional specular direction.
关键词： Scattering cancellation,Array Theory,metasurfaces,RCS reduction,Radar Cross Section,Bragg’s law,Generalized Snell-Descartes’ law,Schelkunoff Polynomial Method,Artificial Magnetic Conductor,Fermat’s principle,Huygens’ principle,Checkerboard
更新于2025-09-11 14:15:04
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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 - Broadband Full Polarimetric Scatterometry for Monitoring Soil Moisture and Vegetation Properties Over a Tibetan Meadow
摘要： A scatterometer is installed on a meadow over the Tibetan Plateau in August 2017 to measure the full polarimetric backscattering coefficient ??0 over a wide frequency range (1 - 10 GHz) year-round. In this paper we describe the setup of scatterometer as well as the activities undertaken to test the reliability of the system. The measured radar cross section of a dihedral reflector matches the theoretical model for 3 – 10 GHz after the calibration. The temperature-induced systematic error in the radar return will be accounted for by using the antenna cross coupling as a reference. For the retrieval of ?0 the frequency-dependent antenna radiation pattern and the site geometry are accounted for. Fading will be dealt with by using frequency agility techniques.
关键词： Radar cross section calibration,Time-domain gating,Tibetan Plateau,Broadband,Scatterometer
更新于2025-09-10 09:29:36
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Directly Printable Frequency Signature Chipless RFID Tag for IoT Applications
摘要： This paper proposes a low-cost, compact, flexible passive chipless RFID tag that has been designed and analyzed. The tag is a bowtie-shaped resonator based structure with 36 slots; where each patch is loaded with 18 slots. The tag is set in a way that each slot in a patch corresponds to a metal gap in the other patch. Hence there is no mutual interference, and high data capacity of 36 bits is achieved in such compact size. Each slot corresponds to a resonance frequency in the RCS curve, and each resonance corresponds to a bit. The tag has been realized for Taconic TLX-0, PET, and Kapton?HN (DuPontTM) substrates with copper, aluminum, and silver nanoparticle-based ink (Cabot CCI-300) as conducting materials. The tag exhibits flexibility and well optimized while remaining in a compact size. The proposed tag yields 36 bits in a tag dimension of 24.5 × 25.5 mm2. These 36 bits can tag 236 number of objects/items. The ultimate high capacity, compact size, flexible passive chipless RFID tag can be arrayed in various industrial and IoT-based applications.
关键词： Radio Frequency Identification (RFID),Radar Cross-Section (RCS),backscattering,Chipless
更新于2025-09-10 09:29:36
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Compact Scalable Modeling of Chipless RFID Tag Based on High-Impedance Surface
摘要： This paper proposes a compact model for chipless radio frequency identification (RFID) tag. This compact scalable model consists of capacitors, inductors, and resistors of which their values are directly described by the physical dimension of the chipless tag. Moreover, based on this compact model, radar cross section of chipless RFID tag is predicted, by analyzing polarizability based on surface current distribution in different modes. To validate the proposed model, a 5-bit chipless RFID tag based on high-impedance surface (HIS) is presented, with good agreement among modeled, simulated, and measured results. A wide range of physical parameters have also been validated to show the scalability. This compact scalable model of chipless RFID tag not only simplifies the tag design, but also provides an insight understanding of the HIS structure.
关键词： radar cross section (RCS),high-impedance surface (HIS),equivalent circuit modeling,Chipless radio frequency identification (RFID) tag,surface current distribution
更新于2025-09-10 09:29:36
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DUAL-BAND COMPOSITE WIDEBAND ABSORBING MATERIAL FOR BROADBAND ANTENNA IN-BAND RADAR CROSS SECTION REDUCTION
摘要： A composite wideband absorbing material (WAM) covering dual bands is designed, to reduce the in-band radar cross section (RCS) for broadband antenna in this paper. The upper layer is a traditional absorber while the lower one is a dual-band frequency selective surface (FSS), which is formed by a square ring and an improved Jerusalem cross structure. The absorbing band has been broadened to 112% compared with the magnetic sheet without FSS. Over C and X bands, the absorption rate is over 90%. By using the FSS-based WAM as the ground plane of a Vivaldi antenna, substantial RCS reduction is obtained from 2–18 GHz. Moreover, the RCS is reduced remarkably over ?80?–80? incident angles except for minority angles, with the radiation performance preserved at the same time. The experimental results are in good agreement with the simulated ones.
关键词： Vivaldi antenna,frequency selective surface,radar cross section reduction,dual-band,composite wideband absorbing material
更新于2025-09-10 09:29:36
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RCS Reduction and Gain Enhancement for the Circularly Polarized Array by Polarization Conversion Metasurface Coating
摘要： High-gain, the ultra-wide band circularly polarized (CP) array with low radar cross section (RCS) is proposed based on (UWB) polarization conversion metasurface (PCM) coating. A chessboard-like coating is formed by a mess of arrow-shaped PCM elements which have UWB and high polarization conversion ratio. The coating is distributed beneath the dipoles and behaving as a reflector. With the PCM beneath each dipole, the CP radiation is achieved and enhanced in a low profile by the radiating wave and the reflected wave, which have equal amplitude and 90° phase difference. With the chessboard-like coating, the incident wave is converted into the equal amplitude and out-of-phase reflected waves, which will cancel each other to reduce the backward scattering. The performances of the array are validated by both simulations and measurements. The results show that the left-hand CP radiation is achieved in 11.25 GHz to 12.31 GHz with the RCS being reduced for more than 4.8 dB in 10.5 GHz to 35.1 GHz.
关键词： high gain,circular polarization,low profile,radar cross section (RCS),polarization conversion metasurface (PCM)
更新于2025-09-09 09:28:46
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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 - A Modified Wave Spectrum for Modeling in Remote Sensing Problems
摘要： In this paper we present a new directional spectrum based on both oceanological and remote sensing data. The model is compared with popular ocean wave models used for remote sensing problems of T. Elfouhaily, P.A. Hwang and V. Kudryavtsev. It is shown that the modified wave spectrum is a good choice for L band RCS modeling for moderate incidence angles. It is also shown that the modeling results with the modified wave spectrum are in agreement with experimental data. In a region after spectral peak the model is presented in a form of power-law dependency of spectral density on frequency, where power is different for different wave ranges. It allows carrying out analytical transformations easily. An asymmetrical angular spreading function is used in a spectral model.
关键词： mean square slopes,directional spectrum,remote sensing,ocean surface wave spectrum,radar cross section
更新于2025-09-09 09:28:46
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[IEEE 2018 International Conference on Radar (RADAR) - Brisbane, Australia (2018.8.27-2018.8.31)] 2018 International Conference on Radar (RADAR) - Using VHF Navigation Aid to Estimate Radar Cross Section of Airliners by Inverting the Radar Equation
摘要： The VHF Omnidirectional Range (VOR) navigation aid system can be used as donor of signal for passive radar experiments. An experiment was set up close to a VOR beacon to detect airliners and to analyze their radar cross section in the configuration of the trials, the adapted signal processing and the detection results obtained for one of the detected targets. The radar cross section (RCS) was estimated from the computation of power budget in radar equation. An analysis of the evolution of the RCS is given in function of the attitude of this detected target in azimuth and elevation. Mean values of RCS for many models of airliners detected during the trial campaign and deduced by the same approach are then presented.
关键词： passive radar,bistatic,VOR,radar cross section,VHF
更新于2025-09-04 15:30:14
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[IEEE 2018 International Conference on Radar (RADAR) - Brisbane, Australia (2018.8.27-2018.8.31)] 2018 International Conference on Radar (RADAR) - Rocket Detection Using Passive Radar - Challenges and Solutions
摘要： In the paper selected aspects of rocket detection with the use of passive radar are analyzed. The bistatic radar cross-section of a rocket is calculated using electromagnetic simulator. Next, the radar equation for passive radar is analyzed taking into consideration the radiation patterns of the transmitter antenna. Limitations of integration time are also discussed. The theoretical analysis is supplemented with measurement results – the processing results of a rocket observed with a DVB-T based passive radar are shown and analyzed.
关键词： DVB-T,passive radar,bistatic radar cross-section,electromagnetic simulator,rocket detection
更新于2025-09-04 15:30:14
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A Near-Field to Far-Field RCS Measurement Method for Multiple-Scattering Target
摘要： It is challenging to perform the near-field to far-field transformation with a high precision for the multiple-scattering targets using the conventional monostatic radar cross section (RCS) measurement. In this paper, a novel near-field to far-field transformation method with bistatic RCS measurement is proposed. First, the RCS measurement is perceived as a double radiation model. Doing this, the relationship of near-field data and far-field data at different angles is derived, and the convolution function is given under the cylindrical wave. Second, the near-field scattering data are acquired using the proposed bistatic RCS measurement method that combines one transmission and multiple receptions with the rotation of a revolving table. The near-field data are then extrapolated twice with the convolution function, and the far-field RCS are obtained accordingly. Moreover, this paper also analyzes the truncation angular and sampling intervals for the measurement consideration. Finally, the effectiveness and the high precision of the proposed transformation approach for the multiple-scattering target are demonstrated using the numerical simulations and the experimental characterization with an example of dihedral structures.
关键词： near-field to far-field transformation,multiple-scattering target,sampling interval,Bistatic radar cross section (RCS) measurement,truncation angular
更新于2025-09-04 15:30:14