Article
Engineering, Electrical & Electronic
Rafael Gonzalez Ayestaran, Marcos Rodriguez Pino, Paolo Nepa, Borja Imaz-Lueje
Summary: The feasibility of a novel near-field focusing technique based on time-modulated arrays is studied. It shows the potential for multiuser focusing at different frequencies, advantageously exploiting the characteristic side frequencies radiation of TMAs. TMAs are interesting alternatives to other technologies due to their simpler implementation through digital devices and adaptive implementation as required.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Computer Science, Information Systems
Yuanjin Tian, Jing Tan, Yanwei Zhang, Ke Wang, Xiao Dong, Hailin Li
Summary: Compared with the traditional antenna array, the time-modulated array can increase flexibility, but it is more sensitive to random errors due to the introduction of time switches.
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
Paolo Rocca, Lorenzo Poli, Nicola Anselmi, Andrea Massa
Summary: This article presents a novel clustering method for synthesizing asymmetric shaped beam patterns in subarrayed linear antenna arrays. The definition of the elements aggregations and the corresponding weighting coefficients is achieved through two nested iterative loops. The external loop aims to determine the optimal excitations of a reference fully populated array that fits user-defined pattern masks, while the internal loop is dedicated to synthesizing the best subarrayed layout that provides the closest pattern to the reference one using a k-means-based algorithm that minimizes the total intracluster variations.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Engineering, Electrical & Electronic
Sujoy Mandal, Sujit Kumar Mandal
Summary: In this letter, a novel method for synthesizing power pattern in time-modulated linear array is proposed. It investigates the effects of increasing the maximum power of the main beam on the sideband radiation and total sideband power of the array. Based on this analysis, a cost function is formulated using only the maximum power of the main beam to synthesize the desired pattern with suppressed sideband radiations. Representative numerical results illustrate the computational proficiency and potential viability of the proposed method.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Hongzhi Yang, Lei Wang, Changming Zhao, Haiyang Zhang
Summary: The study investigated a phase-modulated frequency-shifting loop (PM-FSL) with an electro-optic phase modulator (EOPM) and a gain element seeded by a single-frequency laser. By detuning the modulation frequency of the EOPM, a series of sinusoidal frequency-modulated (SFM) pulse doublets with reconfigurable repetition rate and bandwidth were generated. The experiment successfully produced SFM waveforms with bandwidth above 7 GHz by tuning the input RF tone around 14.58 MHz, with the system effectively modeled using a time-delayed interference model.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Xuhui Fan, Junli Liang, Yang Jing, H. C. So, Qiang Geng, Xiaozhe Zhao
Summary: This article proposes a method to generate a set of weights for synthesizing sum or difference patterns with controlled sidelobe level, null, and dynamic range ratio for arbitrary arrays. By decomposing the original optimization problem into subproblems and applying an appropriate step size, the proposed method can accurately control the desired parameters. Extensive experiments demonstrate the effectiveness of the method for various array configurations.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Engineering, Electrical & Electronic
Quanhu Shi, Zhi Zheng, Yan Sun
Summary: A new algorithm for synthesizing large linear and planar arrays is presented, where the large array is partitioned and weighted at subarray level. The algorithm formulates the pattern synthesis problem as a weight matching problem and uses the K-means approach to solve it, resulting in a pattern with lower peak sidelobe level than the state-of-the-art method. Numerical results demonstrate the effectiveness of the proposed algorithm.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Jianhua Yang, Feng Yang, Peng Yang, Zhiyu Xing
Summary: This article proposes a novel hybrid methodology that jointly optimizes the ring radii, clusters partitions, and clusters excitations to address the clustering problem of concentric ring arrays (CRAs). It utilizes convex programming for the optimization of excitation variables due to their convex nature. For the optimization of ring radii and clusters partitions, a subproblem is formulated using mixed-integer programming with linear constraints, which is effectively solved using a developed technique called mixed-integer linear-constraint genetic algorithm (MILCGA). A set of representative numerical experiments demonstrate the effectiveness of the proposed method and highlight its potential as a promising solution for CRAs to achieve a suitable tradeoff between costs, robustness, flexibility, and beam control performances.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Ananya Mukherjee, Sujit Kumar Mandal, Rowdra Ghatak
Summary: A new technique for fast and accurate extraction of faulty element position from multipatterned time-modulated arrays has been proposed, utilizing a novel rank-based population and degraded dual-beam patterns. This combination leads to higher convergence speed in detecting faulty elements.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Engineering, Electrical & Electronic
Ugur Yesilyurt, Ihsan Kanbaz, Suleyman Kuzu, Ertugrul Aksoy
Summary: The study analyzes the synthesis of the time-modulated array in terms of enhancing the harmonic component and steering its direction, proposing a dual-phase variable pulse amplitude time sequence signal. The periodic convolution operator demonstrates superior ability in completely suppressing unwanted harmonics, while the proposed method provides convenience in reconfiguration solely through methodological analysis. The harmonic-enhancement capability and steering flexibility of the approach are shown through representative examples.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Engineering, Electrical & Electronic
Yongtai Yin, Yuexian Wang, Tiantian Dai, Ling Wang
Summary: This paper proposes a novel direction of arrival (DOA) estimation method based on smoothed sparse reconstruction with time-modulated linear arrays (TMLA). By analyzing the noise variation after time modulation, a closed-form expression for the noise covariance is derived under the optimized unidirectional phase center motion time sequence scheme. A reweighted continuous function is then designed for smooth approximation to l(0)-norm based on the orthogonality between the signal subspace and the noise subspace. Simulation results demonstrate that the proposed method outperforms conventional DOA estimation methods with time-modulated arrays in terms of estimation accuracy and computational complexity, especially in scenarios with small snapshot and low signal-to-noise ratio.
Article
Engineering, Electrical & Electronic
Andrea Giovannini, Jacopo Nanni, Luis Fernandez, Giacomo Paolini, Federico Perini, Enrico Lenzi, Anne-Laure Billabert, Alessandra Costanzo, Jean-Luc Polleux, Diego Masotti, Jean-Marc Laheurte, Giovanni Tartarini
Summary: The study proposes a solution combining Radio over Fiber (RoF) and Time Modulated Arrays (TMA) in In-Building scenarios, where an effective control of the maximum deviation of multiple beams emitted by TMA can be achieved by maintaining a small length difference among the output branches of the optical splitter.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Telecommunications
Fei Zhao, Jun He, Sanyou Zeng, Changhe Li, Qinghui Xu, Zhigao Zeng
Summary: This study introduces a new form of optimization problems for antenna array pattern synthesis, which reduces complexity by changing the objective function and design variables. The effectiveness and advantages of the proposed method are validated through synthesis experiments.
CHINA COMMUNICATIONS
(2022)
Article
Optics
Hongzhi Yang, Marc Brunel, Marc Vallet, Haiyang Zhang, Changming Zhao
Summary: A real-time spectral analysis method was experimentally demonstrated using a frequency-shifting loop and an electrooptic phase modulator. Different output patterns were observed depending on the type of seed laser used, with pulse doublets emitted for single-frequency lasers and frequency-to-time mapping demonstrated for polychromatic seeds with a resolution of 400 kHz. The nonlinear mapping of spectral power with temporal output was shown to align with theoretical predictions, with potential applications in integrated systems discussed.
Article
Engineering, Electrical & Electronic
Marco Salucci, Arianna Benoni, Giacomo Oliveri, Paolo Rocca, Baozhu Li, Andrea Massa
Summary: This article focuses on the electromagnetic planning of static and passive electromagnetic skins in complex urban scenarios with the aim of enhancing the electromagnetic coverage of base-station antennas. The study proposes an innovative system-by-design-based method to optimize wireless links of arbitrary depth implemented through multiple cascaded reflections. Numerical analysis of real-world scenarios is conducted to evaluate the capabilities and potential of the smart electromagnetic environment (SEME).
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Giacomo Oliveri, Francesco Zardi, Paolo Rocca, Marco Salucci, Andrea Massa
Summary: An innovative approach based on an inverse source formulation is introduced to design constrained static-passive electromagnetic skins that comply with complex wireless coverage requirements and urban installation constraints. The proposed method leverages the ill-posedness/nonuniqueness of the problem to derive a closed-form expression for the synthesis of SP-EMSs. Results from numerical experiments demonstrate the effectiveness and computational efficiency of the proposed method as a suitable tool for implementing smart electromagnetic environments (SEME).
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Pietro Rosatti, Marco Salucci, Lorenzo Poli, Andrea Massa
Summary: This paper addresses the computationally efficient solution of multiobjective optimization problems in the design of modern electromagnetic systems, such as mm-wave automotive radar antennas. It proposes a novel system-by-design method that effectively explores the solution space and provides a set of optimal tradeoff solutions. The MO-SbD method integrates evolutionary-inspired concepts and operators with AI and ML techniques, resulting in high computational efficiency and significant time savings compared to competitive MOP solution strategies. Representative numerical results are reported to assess the effectiveness of the proposed optimization method in designing mm-wave automotive radar antennas.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Chemistry, Analytical
Marco Salucci, Giacomo Oliveri, Mohammad Abdul Hannan, Renzo Azaro, Andrea Massa
Summary: This paper presents the design of a wide-band wide-beam circularly-polarized slot-coupled radiating element for wide-angle scanning arrays. The designed radiator generates wide-beam patterns with rotational symmetry and high polarization purity by using a simple geometry composed of a primary and secondary element. The synthesis was carried out using a customized version of the System-by-Design method to achieve circular polarization and wide-band impedance matching.
Article
Engineering, Electrical & Electronic
Giacomo Oliveri, Nicola Anselmi, Marco Salucci, Lorenzo Poli, Andrea Massa
Summary: This paper addresses the design of data acquisition systems in microwave imaging. The scattering data collection is formulated within a Compressive Sampling (CoSamp) framework and solved by minimizing the bound of the restricted isometry constant (RIC) of the observation matrix. A new incoherence-based RIC bound is derived to take into account the physics of the microwave imaging system. Numerical experiments are conducted to assess the proposed approach's information acquisition capabilities and its impact on the performance of the subsequent Compressive Sensing (CoSens)-based inversion compared to standard Nyquist-Shannon-based sampling techniques.
JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Nicola Anselmi, Paolo Rocca, Andrea Massa
Summary: This paper analyzes the tolerance of reconfigurable monopulse linear arrays on uncertainties of the excitation amplitudes. It introduces a method based on interval arithmetic (IA) rules and computes analytic bounds for the sum and difference power patterns. The paper proposes an innovative strategy for worst-case performance analysis when dealing with tolerances on different parts of the beam forming network, utilizing the reliability and computational efficiency of the IA-based formulation.
JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS
(2023)
Article
Chemistry, Analytical
Ruibo Li, Peng Li, Paolo Rocca, Aaron Angel Salas Sanchez, Liwei Song, Xinghua Li, Wanye Xu, Zijiao Fan
Summary: In this work, a low-profile, wideband, and high-gain antenna array based on a novel double-H-shaped slot microstrip patch radiating element was proposed. The array showed stability against high temperature variations. The antenna element operated in the frequency range of 12 GHz to 18.25 GHz, with a 41.3% fractional bandwidth (FBW) and a peak gain of 10.2 dBi. The fabricated 4x4 planar array, equipped with a flexible 1 to 16 power divider, generated a pattern with a peak gain of 19.1 dBi at 15.5 GHz. Experimental results demonstrated that the array performance remained stable in a wide temperature range, from -50 degrees C to 150 degrees C.
Proceedings Paper
Engineering, Electrical & Electronic
Marco Salucci, Giacomo Oliveri, Paolo Rocca, Lorenzo Poli, Arianna Benoni, Pietro Da Ru, Francesco Zardi, Andrea Massa
Summary: The Smart ElectroMagnetic Environment (SEME) is a groundbreaking paradigm that will be a fundamental aspect in the design of next generation wireless communication systems. It introduces the idea that the environment should be considered as an additional degree-of-freedom (DoF) to enhance the overall Quality-of-Service (QoS) instead of a hindrance to the propagation of electromagnetic (EM) waves. This article provides an overview of the foundational concepts and ideas of SEME, examines recent implementations, and explores possible future trends in this emerging research area.
2023 17TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION, EUCAP
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Luca Tosi, Nicola Anselmi, Paolo Rocca, Andrea Massa
Summary: This study addresses and reformulates the analysis and synthesis of phased array (PA) antennas in a Quantum Computing (QC) framework by adopting the Quantum Fourier Transform (QFT) as an alternative to the classical discrete Fourier transform (DFT). Numerical results from simulation of quantum devices are also provided to support the proposed methodology.
2023 17TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION, EUCAP
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Giacomo Oliveri, Arianna Benoni, Paolo Rocca, Marco Salucci, Andrea Massa
Summary: The concept of Reconfigurable Intelligent Surfaces (RISs) has garnered significant interest in academia and industry due to their potential use in 6G networks. However, there are still important challenges in terms of technology and methodology that need to be addressed to effectively deploy and utilize RISs, particularly in integrating them into existing wireless environments. This work aims to present the recent advances and emerging solution strategies for RIS configuration and adaptation in next generation networks.
2023 17TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION, EUCAP
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Giacomo Oliveri, Paolo Rocca, Marco Salucci, Andrea Massa
Summary: The availability of inexpensive phased array technologies capable of supporting wide scanning angles with stable performance is of increasing interest. However, popular planar phased arrays usually suffer from scan blindness and limitations to the field-of-view caused by the inter-element mutual coupling. Passive static electromagnetic skins employed as artificial proximity objects (APOs) have recently gathered attention for stabilizing the active element impedance in wide-angle scanning arrays.
2023 17TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION, EUCAP
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Giacomo Oliveri, Lorenzo Poli, Paolo Rocca, Marco Salucci, Francesco Zardi, Andrea Massa
Summary: Reconfigurable passive electromagnetic skins (RP-EMSs) are essential for implementing the Smart EM Environment paradigm in future wireless communications. However, there are still challenges in the design, optimization, control, and implementation of cost-effective and efficient RP-EMSs. This work reviews the recent advances and trends in this field.
2023 17TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION, EUCAP
(2023)
