Results 21 to 30 of about 927 (180)

A Novel Terahertz Frequency Scanning Antenna Based on Slotted Waveguide Arrays

Leida xuebao, 2018
This research proposes a novel terahertz frequency scanning antenna based on slotted waveguide arrays, and the antenna consisted of 31 elements in a linear array.
Li Shichao, Hou Peipei, Qu Jian, Hao Congjing, Jia Qu, Li Gang, Li Chao   +6 more
doaj   +1 more source

Optimal Mismatched Filter Design by Combining Convex Optimization With Circular Algorithm

IEEE Access, 2022
Mismatched filters (MMF) have been intensively explored for linear-frequency modulation (LFM) waveform sidelobe reduction. Unlike other design strategies, the use of convex optimization (CO) techniques is able to find the optimal design.
Ling Jin, Ju Wang, Yi Zhong, Duo Wang
doaj   +1 more source

Range sidelobe suppression for OFDM-integrated radar and communication signal

The Journal of Engineering, 2019
To improve the RadCom system of performing both data transmission and radar-sensing functions, here a waveform design method for orthogonal frequency division multiplexing (OFDM) signal is proposed to solve the problem of high range sidelobe level in ...
Jiajun Zuo, Ruijuan Yang, Shaohua Luo, Yugang Zhou   +3 more
doaj   +1 more source

Sidelobe Reduction in the Pulse-Compression Radar Using Synthesis of NLFM Laws

International Journal of Antennas and Propagation, 2013
It is well known that in the pulse-compression radar theory, the sidelobe reduction using synthesis of some proper nonlinear FM (NLFM) laws represents a major research direction.
Iulian-Constantin Vizitiu
doaj   +1 more source

Sidelobe suppression for accelerating beams

Optics Express
Although the control of trajectory, amplitude and beam-width in accelerating beams have been extensively investigated, sidelobes manipulation of such beams, which is required in many applications, has been surprisingly under-researched. This paper presents an approach for the generating of accelerating beams with significantly reduced sidelobes.
Cilong Zhang, Yanbo Zhao, Qiaofeng Tan
openaire   +2 more sources

A Comparative Study on Sideband Optimization in Time-Modulated Arrays

International Journal of Antennas and Propagation, 2014
A comparative analysis of the three different methods known as sideband level suppression (SBL), sideband radiation suppression (SR), and sideband bound suppression (SB) which are used in sideband calculations for time-modulated arrays (TMAs) is ...
Ertugrul Aksoy, Erkan Afacan
doaj   +1 more source

Wood‐Derived Nanocellulose‐Biocarbon Fresnel‐Zone Plate Lenses for Sub‐THz Frequency Applications

Advanced Materials Technologies, EarlyView.
Wood‐derived nanocellulose and lignin‐based biocarbon were combined to fabricate fully bio‐based Fresnel zone plate (FZP) lenses for sub‐terahertz frequencies. These sustainable FZP lenses exhibit low dielectric loss and high directivity, achieving performance comparable to that of metallic references, and remain functional under environmental stress ...
Riikka Haataja, Mikko Kokkonen, Niina Halonen, Sami Myllymäki, Umair Rafique, Mandeep Singh, Ossi Laitinen, Heli Jantunen, Kristiina Oksman, Henrikki Liimatainen   +9 more
wiley   +1 more source

Conformal Reconfigurable Intelligent Surfaces: A Cylindrical Geometry Perspective

Advanced Electronic Materials, EarlyView.
Cylindrical reconfigurable intelligent surfaces are explored for low‐complexity beam steering using one‐bit meta‐atoms. A multi‐level modeling approach, including optimization‐based synthesis, demonstrates that even minimal hardware can support directive scattering.
Filippo Pepe, Ivan Iudice, Giuseppe Castaldi, Marco Di Renzo, Vincenzo Galdi   +4 more
wiley   +1 more source

Chaotic Coding for Interference Suppression of Digital Ionosonde

Remote Sensing, 2023
External interference in ionospheric sounding seriously degrades the quality of echo signals and data; thus, it should be eliminated. This paper presents a method for suppressing interference using chaotic coding with a set of Bernoulli map sequences ...
Sijia Han, Wei Guo, Peng Liu, Te Wang, Caiyun Wang, Qingyu Fang, Jian Yang, Lingling Li, Dapeng Liu, Jianping Huang   +9 more
doaj   +1 more source

Ultrasonic Rainbow: A Meta‐Transducer for Frequency‐Selective Elastic Wave Control via Dithering‐Based Wavenumber Tuning

Advanced Intelligent Systems, EarlyView.
A piezoelectric meta‐transducer generates an ultrasonic rainbow, steering guided elastic waves to different angles according to frequency. A dithering‐based binary electrode design enables a closer realization of the target wavenumber filter, improving directional purity and suppressing unwanted lobes. Numerical and experimental validation demonstrates
Masoud Mohammadgholiha, Jochen Moll, Kilian Tschöke, Carsten Kruska, Sylvia E. Gebhardt, Luca De Marchi   +5 more
wiley   +1 more source