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Blindness-free beam scanning antenna with array of array architecture: principle,design,and experiment

science China(Information sciences) 2024年第3期67卷 209-224页

作者： Jianxu SUN Yujian CHENG School of electronic science and Engineering University of electronic science and technology of China

This paper presents a 66–76-GHz sparsely-excited phased array antenna with the array of array(Ao A) architecture for eliminating the blindness and suppressing the grating lobe when scanning. For the array antennas printed on the thick dielectric layers with high relative permittivity, scanning blindness appears and seriously impacts the radiation performance. To address this issue, the Ao A topology is developed first. It finds that the scanning blindness appears due to the coupling of the radiating Floquet modes to the non-radiating surface wave(SW) modes. Therefore, the array is divided into two types of domino *** inner-phase distributions are introduced into the domino subarrays to break the one-to-one relationship between the Floquet mode and the SW mode. Then, the blindness inside ±60° scanning volume is eliminated by the aperiodic subarrays. Meanwhile, the aperiodic inner-phase distributions enhance the aperiodicity of the array and contribute to suppressing the grating lobe when scanning. Next, the meta-surface-based dipole with the shorted post is chosen as the unit cell for the proposed aperiodic array. Based on these methods,the array achieves the wide-scanning performance of ±60° in the E-plane and ±30° in the H-plane, without the blindness and the grating lobe. Finally, the 16×16 array is built and simulated with the dimension of32 mm × 32 mm. At the highest operating frequency, the simulated gains are 28.42, 25.17, and 24.01 d Bi when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. Compared to the ideal gain, it shows that the simulated radiation efficiency is about 84.13%, 62.08%, and 35.23% when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. The worst transmission coefficient, i.e., the worst isolation, is-11.97 d B between the central element and its two adjacent elements in the E-plane. The array prototypes are fabricated, and the experiments are carried out to ver

关键词： 6G communication systems phased array AoA aperiodic subarray wideband wide-scanning surface-wave scanning blindness grating lobe

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Highly efficient conversion from classical guided waves to topological chiral edge states

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Chinese Optics Letters 2024年第2期22卷 221-226页

作者：韩建飞梁锋赵玉林丁霄汪相如赵德双王秉中 School of Physics University of Electronic Science and Technology of ChinaChengdu 611731China School of Optoelectronic science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Electromagnetic topological chiral edge states mimicking the quantum Hall effect have attracted a great deal of attention due to their unique features of free backscattering and immunity against sharp bends and ***,the matching techniques between classical waveguides and the topological one-way waveguide deserve more attention for real-world *** this paper,a highly efficient conversion structure between a classical rectangular waveguide and a topological one-way waveguide is proposed and demonstrated at the microwave frequency,which efficiently converts classical guided waves to topological one-way edge states.A tapered transition is designed to match both the momentum and impedance of the classical guided waves and the topological one-way edge *** the conversion structure,the waves generated by a point excitation source can be coupled to the topological one-way waveguide with very high coupling efficiency,which can ensure high transmission of the whole system(i.e.,from the source and the receiver).Simulation and measurement results demonstrate the proposed *** investigation is beneficial to the applications of topological one-way waveguides and opens up a new avenue for advanced topological and classical integrated functional devices and systems.

关键词： guided waves highly efficient conversion photonic crystals topological chiral edge states

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A Wideband High-Gain Sawtooth Slot Array Antenna with Frequency-Scanning at Lower Frequency and Fixed-Beam at Higher Frequency

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Chinese Journal of electronics 2024年第2期33卷 463-471页

作者： Qiang SUN Yongling BAN Jun HU School of electronic science and Engineering University of Electronic Science and Technology of China

Exploring the multifunctional array antenna suitable for complex communication environment has very important research value. In this paper, a millimeter wave(mm-wave) double longitudinal sawtooth slot array antenna(DLSA) based on substrate integrated waveguide(SIW) technology is proposed, which has wideband, highgain and novel beam characteristics. Two irregular longitudinal slots are etched on the SIW conductor surface as the radiation structure. To improve the bandwidth of the DLSA, the metallized vias are added at the transition point of the slots to construct multiple resonant frequency points. By adjusting the size of the slots and the position of the metallized vias, the phase constant can be regulated, and the unusual beam characteristics can be obtained. That is to say, in the lower frequency band, the beam pointing angle increases with frequency. In the higher frequency band,the beam pointing angle is maintained at a fixed angle. Finally, to improve the antenna gain, a 16 × 8 DLSA is fabricated, measured and discussed. The proposed antenna has an impedance matching bandwidth close to 9.7 *** 27 to 33 GHz, the beam pointing angle changes from 8° to 29°. From 33 to 37 GHz, the beam pointing angle is fixed at 29°, and the pointing angle error range is ±1°. In addition, the measured maximum gain is 22.9 d Bi at32 GHz.

关键词： Antenna measurements Slot antennas Surface waves Resonant frequency Gain measurement Conductors Frequency measurement

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Miniaturized power detection module operating in millimeter wave band

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Journal of electronic science and technology 2024年第2期22卷 69-76页

作者： Xiang Zhou Zhi-Yong Zhong School of electronic science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real *** is highly prospective in military and scientific *** this paper,a broadband power detection module operating at 26.5 GHz-40.0 GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold *** module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 ***,the temperature compensation circuit is also applied to improve the measurement *** a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is *** designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 *** endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites.

关键词： Diode Miniaturization Power detection Temperature compensation

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Energy consumption optimization for edge computing-supported cellular networks based on optimal transport theory

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science China(Information sciences) 2024年第2期67卷 201-218页

作者： Xiangyu LV Xiaohu GE Yi ZHONG Qiang LI Yong XIAO School of electronic Information and Communications Huazhong University of Science and Technology

With advancements in mobile communication technologies, there have been multiple user device(UD) connections to cellular networks. Because of changes in the spatial distribution of UDs and application requirements, the traditional offloading mechanism based on the nearest distance will result in heavy loads for some base stations(BSs). Because there is a high-order relationship between the energy consumption of the BS processing tasks and the number of computing tasks, the traditional offloading mechanism will result in high energy consumption, and UD’s offloading decision must be dynamically adjusted. The offloading decision of UDs is optimized based on detailed information about various parameters associated with a network from the standpoint of distribution. This information includes details regarding the spatial distribution of UDs,application requirements, and the offloading period of computing tasks. Based on optimal transport theory,an energy consumption optimization algorithm is suggested to lower the total amount of energy consumed by the offloading process of UDs’ computing tasks by reasonably planning the offloading BSs of the UDs in the networks. The simulation results show that the proposed offloading mechanism based on energy consumption optimization reduces the total energy consumption of the offloading process by 28.09% when compared to the traditional offloading mechanism, and the traffic managed by each BS is balanced.

关键词： optimal transport theory edge computing energy consumption reduction dynamic voltage frequency scaling

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A fast forward computational method for nuclear measurement using volumetric detection constraints

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Nuclear science and Techniques 2024年第2期35卷 47-63页

作者： Qiong Zhang Lin-Lv Lin University of electronic science and technology of China Chengdu 610000China

Owing to the complex lithology of unconventional reservoirs,field interpreters usually need to provide a basis for interpretation using logging simulation *** the various detection tools that use nuclear sources,the detector response can reflect various types of information of the *** Monte Carlo method is one of the primary methods used to obtain nuclear detection responses in complex ***,this requires a computational process with extensive random sampling,consumes considerable resources,and does not provide real-time response ***,a novel fast forward computational method(FFCM)for nuclear measurement that uses volumetric detection constraints to rapidly calculate the detector response in various complex environments is ***,the data library required for the FFCM is built by collecting the detection volume,detector counts,and flux sensitivity functions through a Monte Carlo ***,based on perturbation theory and the Rytov approximation,a model for the detector response is derived using the flux sensitivity function method and a one-group diffusion *** environmental perturbation is constrained to optimize the model according to the tool structure and the impact of the formation and borehole within the effective detection ***,the method is applied to a neutron porosity tool for *** various complex simulation environments,the maximum relative error between the calculated porosity results of Monte Carlo and FFCM was 6.80%,with a rootmean-square error of 0.62 *** field well applications,the formation porosity model obtained using FFCM was in good agreement with the model obtained by interpreters,which demonstrates the validity and accuracy of the proposed method.

关键词： Nuclear measurement Fast forward computation Volumetric constraints

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Sub-Nyquist sampling-based wideband spectrum sensing:a compressed power spectrum estimation approach

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Frontiers of Computer science 2024年第2期18卷 139-145页

作者： Jilin WANG Yinsen HUANG Bin WANG National Key Laboratory of science and technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In this paper,we introduce a sub-Nyquist sampling-based receiver architecture and method for wideband spectrum *** of recovering the original wideband analog signal,the proposed method aims to directly reconstruct the power spectrum of the wideband analog signal from sub-Nyquist *** that power spectrum alone is sufficient for wideband spectrum *** only the covariance matrix of the wideband signal is needed,the proposed method,unlike compressed sensing-based methods,does not need to impose any sparsity requirement on the frequency *** proposed method is based on a multi-coset sampling *** exploiting the inherent sampling structure,a fast compressed power spectrum estimation method whose primary computational task consists of fast Fourier transform(FFT)is *** results are presented to show the effectiveness of the proposed method.

关键词： wideband spectrum sensing sub-Nyquist multicoset sampling FCPSE

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Blockchain-based immunization against kleptographic attacks

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science China(Information sciences) 2024年第7期67卷 172-183页

作者： Changsong JIANG Chunxiang XU Jie CHEN Kefei CHEN School of Computer science and Engineering University of Electronic Science and Technology of China Yangtze Delta Region Institute (Huzhou) University of Electronic Science and Technology of China Department of Mathematics Hangzhou Normal University

Adversarial implementations of cryptographic primitives called kleptographic attacks cause the leakage of secret information. Subliminal channel attacks are one of the kleptographic attacks. In such attacks, backdoors are embedded in implementations of randomized algorithms to elaborately control randomness generation, such that the secrets will be leaked from biased outputs. To thwart subliminal channel attacks, double-splitting is a feasible solution, which splits the randomness generator of a randomized algorithm into two independent generators. In this paper, we instantiate double-splitting to propose a secure randomness generation algorithm dubbed SRG using two physically independent generators: ordinary and public randomness generators. Based on public blockchains, we construct the public randomness generator,which can be verified publicly. Hashes of a sufficient number of consecutive blocks that are newly confirmed on a blockchain are used to produce public randomness. In SRG, outputs from the two generators are taken as inputs of an immunization function. SRG accomplishes immunization against subliminal channel ***, we discuss the application strategies of SRG for symmetric and public-key encryption.

关键词： kleptographic attacks subliminal channel blockchain immunization randomized algorithm

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Dependence of Rydberg-atom-based sensor performance on different Rydberg atom populations in one atomic-vapor cell

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Chinese Physics B 2024年第2期33卷 365-370页

作者：武博姚佳伟吴逢川安强付云起 College of electronic science and technology National University of Defense TechnologyChangsha 410073China

The atomic-vapor cell is a vital component for Rydberg atomic microwave sensors,and impacts on overall capability of Rydberg ***,the conventional analysis approach on effect of vapor-cell length contains two implicit assumptions,that is,the same atomic population density and buffer gas pressure,which make it unable to accurately capture actual response about effect of Rydberg-atom-based sensor performance on different Rydberg atom ***,utilizing a stepped cesium atomic-vapor cell with five different dimensions at the same atomic population density and buffer gas pressure,the height and full width at half maximum of electromagnetically induced transparency(EIT)signal,and the sensitivity of the atomic superheterodyne sensor are comprehensively investigated under conditions of the same Rabi frequencies(saturated laser power).It is identified that EIT signal height is proportional to the cell length,full width at half maximum and sensitivity grow with the increment of cell length to a certain *** the coherent integration signal theory and atomic linear expansion coefficient method,theoretical analysis of the EIT height and sensitivity are further *** results could shed new light on understanding and design of ultrahigh-sensitivity Rydberg atomic microwave sensors and find promising applications in quantum measurement,communication,and imaging.

关键词： Rydberg atom population Rydberg-atom-based receiver stepped atomic-vapor cell

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A highly reliable encoding and decoding communication framework based on semantic information

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Digital Communications and Networks 2024年第3期10卷 509-518页

作者： Yichi Zhang Haitao Zhao Kuo Cao Li Zhou Zhe Wang Yueling Liu Jibo Wei College of electronic science and technology National University of Defense TechnologyChangsha 410073China

Increasing research has focused on semantic communication,the goal of which is to convey accurately the meaning instead of transmitting symbols from the sender to the *** this paper,we design a novel encoding and decoding semantic communication framework,which adopts the semantic information and the contextual correlations between items to optimize the performance of a communication system over various *** the sender side,the average semantic loss caused by the wrong detection is defined,and a semantic source encoding strategy is developed to minimize the average semantic *** further improve communication reliability,a decoding strategy that utilizes the semantic and the context information to recover messages is proposed in the *** simulation results validate the superior performance of our strategies over state-of-the-art semantic coding and decoding policies on different communication channels.

关键词： Semantic information Semantic encoding method Context-based decoding method

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