In this letter, a new frequency selective surface is proposed, which mainly applied to 5G communication. The equivalent circuit method used provide assistance for structural design. This structure can generate dual-frequency passbands and achieve double resonant frequencies 28.1 39.5 GHz. It acquires large enough bandwidths cover 27.5-28.35 38.6-40 GHz, are bands of addition, multi-layer composed one metallic layer two dielectric layers, its unit size 0.56λ × 0.56λ, where λ the wavelength...

This letter proposes a dual-stopband frequency selective surface (FSS) with tightly spaced response characteristics. The metal layer of this FSS structure is composed strip bow-type ring and square type, which forms the center symmetric structure. dual-band can achieve reflection characteristics at 6.29 8.35 GHz, belong to C-band X-band, respectively. In addition, two resonant frequencies be independently controlled for good flexibility. has excellent polarization stability angular...

In this letter, a miniaturized frequency selective rasorber (FSR) based on complementary bandpass surface (FSS) for fifth generation applications is designed. It formed by the superposition of tortuous annular resistive layer and FSS layer. The consists regular octagonal patch two bent metal rings. Four lumped capacitors eight chip resistors are loaded to achieve impedance matching wave absorption. layer, Jerusalem cross structure adopted realize electromagnetic transmission structural...

In this paper, a miniaturized and polarization insensitive frequency selective surface filter with large band ratio (BR) is presented. This structure consists of one metal layer two dielectric layers. The includes parts, the outer square loop providing lower stopband inner pattern higher stopband. has excellent miniaturization characteristics, in particular, unit size only 0.054λ0 thickness 0.014λ0, where λ0 wavelength corresponding to first resonant frequency. Additionally, there layer,...

Accurate measurement of the spinal alignment parameters is crucial for diagnosing and evaluating adolescent idiopathic scoliosis (AIS). Manual subjective time-consuming. The recently developed artificial intelligence models mainly focused on measuring coronal Cobb angle (CA) ignored evaluation sagittal plane. We a deep-learning model that could automatically measure in biplanar radiographs. In this study, our adopted ResNet34 as backbone network, consisting keypoint detection CA measurement....

This paper presents a low-profile metamaterial with ultra-wide band ratio (BR) based on active frequency selective surfaces (AFSSs) to overcome the limited tuning range and suboptimal profile of current designs. The proposed design consists periodic pattern printed top thin substrate bias network bottom, varactor diodes symmetrically integrated into metal layer. Based equivalent circuit model, mechanism wideband is analyzed theoretically. corresponding simulation results indicate that...

In this paper, a highly selective quad-band frequency surface (FSS) with ultra-wideband rejection is presented. The proposed FSS structure was developed by cascading five metallic layers three thin dielectric substrates. are composed of two bent slot layers, square rings, and metal patch. dimensions the unit cell 0.13λ0× 0.18λ0 (λ0 free-space wavelength at first operating frequency). achieves four transmission bands has wide stop-bands located 1 to 5.5 GHz 14 40 GHz, suppressed coefficient...

The development of high-temperature nondestructive testing (NDT) requires ultrasonic transducers with good temperature resistance and high sensitivity for improved detection efficiency. Piezoelectric composite can improve the performance because its electromechanical coupling coefficient adjustable acoustic impedance. In this study, 1-3-2 composites (HTCUTs) based on 0.36BiScO3-0.64PbTiO3 (BSPT), which is preferred piezoelectric materials at 200

Abstract A holographic tensor metasurface (HTM) is proposed from the energy perspective to achieve flexible regulations of polarization and distributions for simultaneous transmissions power information. dual‐polarization receiving with high isolation also enable receptions Based on two metasurfaces, a novel system wireless information (SWIPT) established, which can transmit microwave powers signals by flexibly regulating electromagnetic waves in different polarizations. The HTM generate...

This letter proposed a miniaturized frequency-selective rasorber (FSR). FSR consists of conducting sheet layer with embedded dual-bow resonators and bandpass surface cross-ring slot. The structure exhibits absorption–transmission–absorption (A-T-A) characteristics that shows excellent transmission performance in 2.4 GHz band. unit size is 0.113 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\lambda...

The transmission of high-frequency signals over long distances depends on the ionosphere’s reflective properties, with selection operating frequencies being closely tied to variations in ionosphere. accurate prediction ionospheric critical frequency foF2 and other parameters low latitudes is great significance for understanding changes communications. Currently, deep learning algorithms demonstrate significant advantages capturing characteristics In this paper, a state-of-the-art hybrid...

Integrating radio frequency energy harvesting into wireless communications to support simultaneous information and power transfer (SWIPT) is a promising technique extend lifetime of energy-limited cooperative networks. In this paper, multiuser resource optimization for incremental amplify-and-forward orthogonal division multiplexing relaying systems with SWIPT investigated. To maximize the overall achievable rate, multi-dimensional degrees freedom (e.g., allocation, subcarrier assignment,...

As the flight scheduling has always been a key technology which reduces delays and costs. Rational efficient sorting method not only can effectively improve utilization of airport, reduce delay, but also ensure safety incidence sudden accidents. Firstly, we studied application ant colony algorithm in sorting, proposed new is combined with genetic depending on mutation characteristic algorithm; Secondly, minimization objective model that total delay was minimum established based method;...

Most robots in urban search and rescue (USAR) fulfill tasks teleoperated by human operators (Such as controlling robot movement to avoid obstacles explore unknown environments). The operator has know the location of find position target (victim). This paper presents an augmented reality system using a Kinect sensor on customly designed robot. Firstly, Simultaneous Localization Mapping (SLAM) RGB-D cameras is running get posture Secondly, deep learning method adopted obtain target. Finally,...

A data-aided (DA) carrier recovery (CR) method, which can select different coarse frequency estimation (CFE) paths adaptively according to the initial-estimation of offset, is proposed for 2nd Generation Digital Video Broadcasting Satellite (DVB-S2) system accomplish convergence within at most 400 pilot blocks. The well-known two-step CR scheme used consideration precision and speed, whereas both CFE fine (FFE) adopt L&R algorithm as their basic estimator so that same correlation operation...

For the widely coverage of satellite beam, dominated weather-caused attenuation on Ka-band causes asymmetric fading uplink and downlink. The recognized adaptive coding modulation (ACM), a significant mitigation technique in communication systems, mainly focuses improving downlink spectrum efficiency. However, efficiency is always impaired when channel condition poor. In this paper, we propose novel ACM scheme for geostationary (GEO) regenerative which on-board processing based. To be more...

Lead-free piezoelectric material-based ultrasonic transducers have been researched for several years, but the inefficient properties and design difficulties troubled lead-free a long time. To improve performance efficiency of transducers, in this work, an equivalent circuit model intelligent optimization algorithm were combined use transducer design. Firstly, 0.94(Bi0.5Na0.5)TiO3-0.06BaTiO3(BNT-6BT) ceramics prepared characterized. Then, BNT-6BT used to fabricate transducers. An model-based...

This letter designs an orthogonal time-frequency space (OTFS) enabled network-coded multiple access (NCMA) system for enhancing the throughput in high-mobility scenarios. For designed system, impact of power distribution and relative phase offset is theoretically analyzed upper-bound symbol error probability derived into a closed-form expression. To further minimize probability, joint amplitude-phase optimization scheme proposed with using genetic algorithm. Finally, simulation results...

The application of autonomous navigation technology electric crawler tractors is an important link in the development intelligent greenhouses. Aiming at characteristics enclosed and narrow space uneven ground potholes greenhouse planting, to improve intelligence level tractors, this paper develops a system for planting environment based on LiDAR technology. hardware consists five modules: information perception module, control communication motion power module. software composed three...

In this paper, a dual-passband frequency selective surface (FSS) with high angular stability and polarization insensitivity is proposed. The unit structure consists of circular aperture, two annular apertures four cross apertures. designed FSS can achieve double-passband at the interested frequencies 8.45 GHz 12.76 an insertion loss less than 1 dB, it retain stable transmission characteristic incident angle ranging from 0° to 86° for TE mode 83° TM mode. Good agreement between experimental...