Article
Chemistry, Analytical
Xiaolang Shao, Taiyang Hu, Jinyu Zhang, Lei Li, Mengxuan Xiao, Zelong Xiao
Summary: In this paper, an efficient non-iterative beampattern synthesis approach for sparse Frequency diverse array (FDA) is proposed. The proposed method samples a given reference pattern uniformly, constructs a Hankel matrix with the sampled data, and obtains a low-rank approximation of the matrix by low-rank processing. Then, matrix enhancement and matrix pencil methods are used to estimate the parameters of the obtained array. Experimental results show that the proposed method outperforms existing methods in terms of synthesis error, average runtime, and percentage of saving elements.
Article
Chemistry, Analytical
Che Liu, Yanling Guo
Summary: In this study, a circular Gaussian spot emitted by a laser light source was shaped into a rectangular flat-top beam to improve the scanning efficiency of a selective laser sintering scanning system. By optimizing the aspherical cylindrical lens and the focusing lens, the energy uniformity of the flat-top beam was achieved to be over 80%.
Article
Chemistry, Analytical
Minseok Kang, Jaemin Baek
Summary: In this paper, an efficient APS approach for controlling the sidelobe level is proposed. By performing Fourier transform on the projection of the waveform pattern onto the mask template, a set of element excitations is calculated, which can be used to synthesize the desired array pattern. This approach achieves substantial improvements in computation complexity, performance, and ease of implementation compared to conventional methods.
Article
Engineering, Electrical & Electronic
Yong Qiang Hei, Long Yuan Ma, Wen Tao Li, Jin Chao Mou, Xiao Wei Shi
Summary: This article proposes an efficient artificial neural network (ANN) method for time-modulated array (TMA) synthesis, which achieves the desired array pattern by properly defining equivalent excitation and optimizing them using a two-stage ANN framework. The proposed method demonstrates superiority, effectiveness, and efficiency.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Jing Tian, Shiwen Lei, Zhipeng Lin, Yin Gao, Haoquan Hu, Bo Chen
Summary: This letter introduces a robust pencil beam pattern synthesis algorithm that is adaptive to uncertainties in array position. By estimating position variations and solving related PBPS problems, the optimal array excitation is calculated to validate the superiority of the proposed algorithm through simulations.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Sankaravel Prasad, Murugappan Meenakshi, Patnam Hanumantha Rao
Summary: A method for synthesizing multi-beam patterns from a planar phased array antenna to generate three-dimensional shaped and contour patterns is proposed. The method supports dynamically changeable contour shapes and compensates for the influence of the far-field shape.
MICROWAVE AND OPTICAL TECHNOLOGY LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Mingming Xu, Chen Zhang, Haidong Qiao, Qingjun Zhang, Changjiang Deng, Weihua Yu
Summary: In this work, a sparse antenna array with flat-top and sharp cutoff radiation patterns is introduced. The array is composed of 16 antenna elements, realized by applying a symmetrical sparse configuration with uniform excitation phase. The proposed dual-band dual-polarized base station antenna, based on the sparse antenna arrays, demonstrates excellent radiation performance in the frequency bands of 1.71-2.17 and 2.30-2.69 GHz, with compact size and few antenna elements.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Ralph M. van Schelven, Waqas H. Syed, Giorgio Carluccio, Kostas Doris, Anton de Graauw, Andrea Neto, Daniele Cavallo
Summary: In this work, we investigate antenna architectures for dual-mode operation in phased array designs. Planar slot antenna elements are used in array configuration, along with artificial dielectric layers (ADLs) in close proximity, to achieve pattern shaping. The artificial dielectric superstrate supports leaky wave propagation that can be optimized to enhance gain in a specific angular region or expand the array's field of view. By controlling the amplitude and phase of the antenna elements, radiation patterns can be combined to realize either wide or narrow beams. This concept presents advantages for both mm-wave communication and radar applications. A four-element array design fabricated in standard printed circuit board (PCB) technology validates the feasibility of dual-mode operation, with measured results showing good agreement with simulations.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Geochemistry & Geophysics
Jiho Ryu, Dong-Woo Yi, Se-Young Kim, Giwan Yoon
Summary: This letter presents a method to design an elevation beam pattern mask for spaceborne synthetic aperture radar (SAR) to reduce the range ambiguity. The proposed method estimates the power levels of different ambiguous echoes and synthesizes the transmit and receive beam patterns simultaneously using the minimax algorithm.
IEEE GEOSCIENCE AND REMOTE SENSING LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Yan Dong, Xiao Cai, Geyi Wen
Summary: This study proposes a 4x4 circularly polarized antenna array with suppressed sidelobes for electronic toll collection applications. The antenna array is designed using the weighted constrained method of the maximum power transmission efficiency. Different constraints are introduced to control the polarization and sidelobe levels. The optimized distribution of excitations is obtained analytically, and some elements with negligible amplitudes are removed to reduce the array size. The fabricated array meets the requirements of ETC system and demonstrates good circular polarization performance.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2022)
Article
Optics
Hussein Nasrollahi, Mohammad Mahdi Taskhiri, Asghar Keshtkar
Summary: In this paper, a new technique based on the critical angle theorem is presented for designing and analyzing inhomogeneous flat lenses. The designed lenses are frequency independent and can be applied to various inhomogeneous structures.
Article
Engineering, Electrical & Electronic
Haotian Li, Yikai Chen, Shiwen Yang
Summary: This work aims to develop a novel TMA with array-interpolation aperture and ON-OFF time modulation to achieve beam scanning at the carrier frequency. High-precision beam scanning with low SBLs can be realized through interpolation computation at the antenna array level using pseudorandom ON-OFF time modulation and static 1 bit phase control. Compared with existing designs, the proposed TMA requires fewer modulation statuses and significantly facilitates beamscanning control. A forward design strategy is presented to analytically determine the time modulation sequences and static 1 bit phase statuses for specified beam-scanning angles and SLLs. Numerical and experimental results demonstrate the effectiveness of the proposed TMA.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Multidisciplinary Sciences
C. Riemann, L. U. Scholtz, H. B. Gehl, M. Schuermann, H. Sudhoff, I. Todt
Summary: The study evaluated the position of cochlear implant electrodes using 3T MRI scanning, demonstrating that MRI allows accurate determination of the electrode position in the inner ear, providing important information for quality control.
SCIENTIFIC REPORTS
(2021)
Article
Telecommunications
Hend A. Malhat, Anas S. Zainud-Deen, Mohamed Rihan, Mona M. Badway
Summary: This paper investigates the failure detection and pattern correction for time-modulated linear array antennas (TMLAA). The particle swarm optimization (PSO) algorithm is used to detect the locations of failed elements and estimate the on-time duration of the TMLAA. The correction of damaged radiation pattern is achieved via reconfiguring the on-time instants and durations of the RF switches connected to the array elements. The proposed methods are demonstrated to have the capability and efficiency through experiments with TMLAA.
WIRELESS PERSONAL COMMUNICATIONS
(2022)
Article
Optics
Xiaohui Shen, Lingbao Kong, Jiating An
Summary: This paper presents a collimation method for array laser source, which can directly control the shape of the illumination spot on the target by calculating the lens surfaces, and directly constrain the diameter of the lens by setting the initial point coordinates. The size and intensity distribution of the light spot irradiated by the light source to the target position were simulated by establishing a ray tracing model, and the whole process was calculated using MATLAB software. The corresponding lens model can be obtained by fitting discrete coordinate points using Solid Works, and simulation tests were conducted using the optical design software ZEMAX.
OPTICS AND LASERS IN ENGINEERING
(2023)
