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W-Band High-Efficiency Waveguide Slot Array Antenna with Low Sidelobe Levels Based on Silicon Micromachining technology

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Chinese Journal of electronics 2022年第4期31卷 665-673页

作者： YAO Shisen CHENG Yujian BAI Hang FAN Yong university of electronic science and technology of china

A high-efficiency waveguide slot array antenna with low sidelobe level(SLL) is investigated for W-band applications. The silicon micromachining technology is utilized to realize multilayer antenna architecture by three key steps of selective etching, gold plating and Au-Au bonding. The radiating slot based on this technique becomes thick with a minimum thickness of 0.2 mm and accompanies with the decrease of slot’s radiation ability. To overcome this weakness, a stepped radiation cavity is loaded on the slot. The characteristic of cavityloaded slot is investigated to synthesize the low-SLL array antenna. The unequal hybrid corporate feeding network is constructed to achieve sidelobe suppression in the E-plane. A pair of 16 × 8 low-SLL and high-effciency slot arrays is fashioned and confirmed experimentally. The bandwidth with the radiation effciency higher than 80% is92.3–96.3 GHz. The SLLs in both E-and H-planes are below-19 d B.

关键词： W-band Micromachined waveguide Silicon micromachining Stepped radiation cavity High effciency Sidelobe level (SLL)

A CMOS 4-Element Ku-Band Phased-Array Transceiver

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Chinese Journal of electronics 2022年第6期31卷 1092-1105页

作者： ZHANG Xiaoning YU Yiming ZHAO Chenxi LIU Huihua WU Yunqiu KANG Kai School of electronic science and Engineering University of Electronic Science and Technology of China

This paper presents a Ku-Band fully differential 4-element phased-array transceiver using a standard 180-nm CMOS process. Each transceiver is integrated with a 5-bit phase shifter and 4-bit attenuator for high-resolution radiation manipulation. The front-end system adopts time-division mode, and hence two low-loss T/R switches are included in each channel. At room temperature, the measured root-mean-square(RMS) phase error is less than 5.5°. Furthermore, the temperature influence on passive switched phase shifters is analyzed.Meanwhile, an extra phase-shifting cell is developed to calibrate phase error varying with the operating temperatures. With the calibration, the RMS phase error is reduced by 7° at-45 ℃, and 5.4° at 85 ℃. The RMS amplitude error is less than 0.92 dB at 15-18 GHz. In the RX mode, the tested gain is 9.6±1.1 dB at 16.5 GHz with a noise figure of 10.9 dB, and the input P1dB is-15 dBm,while the single-channel’s gain and output P1dB in the TX mode are 11.3±0.4 dB and 9.4 dBm at 16.1 GHz, respectively. The whole chip occupies an area of 5×4.2 mm2and the measured isolation between each two adjacent channels is lower than-23.1 dB.

关键词： Attenuator CMOS Ku-band Phased-array Phase shifter Transceiver Temperature effect

THz trapped ion model and THz spectroscopy detection of potassium channels

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Nano Research 2022年第4期15卷 3825-3833页

作者： Kaicheng Wang Shaomeng Wang Lixia Yang Zhe Wu Baoqing Zeng Yubin Gong School of electronic science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China

Advanced molecular dynamics(MD)simulation and infrared(IR)spectroscopy have been widely adopted to reveal the detailed dynamic process of high-speed selective permeability of potassium channels.Yet these MD simulations cannot avoid the choice of empirical molecular force fields and high transmembrane voltages(as driving electric fields for ions)far exceeding physiological levels.Moreover,the IR spectroscopy method usually requires isotope labels for carbonyl groups of the channels,which may change the original permeation process.Here,we build the terahertz(THz)trapped ion model for the selectivity filter(SF)of potassium channels KcsA based on the density functional theory(DFT)calculation of ion potentials.In this model,the zero-point energy of trapped ions and quantum tunneling effect provide the physical basis for near diffusion limited permeation rates of ions and explain the high driving electric field in MD simulations.Quantitative calculations of zero-point energy and tunneling probability show that the quantum effect assisted knock-on mechanism may help to realize the physiological functions of potassium channels.Furthermore,based on the trapped ion model,we calculated the ion decoherence timescale under the influence of protein environmental noise.We use the quantum optics method to describe the interaction between THz waves and the trapped ion.Then the novel THz spectroscopy approaches through the THz resonance fluorescence and the intense field non-resonant effect are presented theoretically.These are expected to be isotope label-free detective methods of the rapid ion permeation dynamics.

关键词： potassium channels trapped ions zero-point energy quantum tunneling effect terahertz spectrum density functional theory(DFT)calculation

Mixture test strategy optimization for analog systems

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信息与电子工程前沿:英文版 2023年第9期24卷 1302-1315页

作者： Wenjuan MEI Zhen LIU Ouhang LI Yuanzhang SU Yusong MEI Yongji LONG School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China School of Foreign Languages University of Electronic Science and Technology of ChinaChengdu 611731China Glasgow College University of Electronic Science and Technology of ChinaChengdu 611731China School of Integrated Circuit science and Engineering University of Electronic Science and Technology of Chengdu

Since analog systems play an essential role in modern equipment,test strategy optimization for analog systems has attracted extensive attention in both academia and industry.Although many methods exist for the implementation of effective test strategies,diagnosis for analog systems suffers from the impacts of various stresses due to sophisticated mechanism and variable operational conditions.Consequently,the generated solutions are impractical due to the systems’topology and influence of information redundancy.Additionally,independent tests operating sequentially on the generated strategies may increase the time consumption.To overcome the above weaknesses,we propose a novel approach called heuristic programming(HP)to generate a mixture of test strategies.The experimental results prove that HP and Rollout-HP access the strategy with fewer layers and lower cost consumption than state-of-the-art methods.Both HP and Rollout-HP provide more practical strategies than other methods.Additionally,the cost consumption of the strategy based on HP and Rollout-HP is improved compared with those of other methods because of the updating of the test cost and adaptation of mixture OR nodes.Hence,the proposed HP and Rollout-HP methods have high efficiency.

关键词： Fault diagnosis Heuristic searching Dynamic programming Test optimization

Self-powered forest ambient monitoring microsystem based on wind energy hybrid nanogenerators

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science china(Technological sciences) 2022年第10期65卷 2348-2360页

作者： LI BoYuan QIU Yu HUANG Peng TANG WenJie ZHANG XiaoSheng School of electronic science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

In response to the call for zero-carbon energy supply for Internet of Things(IoTs)applications and to get rid of the dependence of traditional distributed IoTs devices on batteries,the invention of nanogenerators that can convert wind energy in the surrounding environment into electrical energy have received widespread attention.Herein,a wind energy hybrid harvester(WH-EH)combining a soft-friction and positive-directional triboelectric nanogenerator(SP-TENG)and a hierarchical rotating electromagnetic nanogenerator(HR-EMG)is reported to construct a self-powered forest environment monitoring microsystem.With the design of thin inner wall beams and comb-shaped electrodes,the SP-TENG is able to change the output into positivedirectional,which can be stored directly in the energy storage device,breaking the limitation of the alternating positive and negative output of conventional TENGs.In addition,the HR-EMG embeds coils in the cup lid to make the most of the available space in the external package.In the WH-EH,a layered structure,including the HR-EMG and SP-TENG is adopted to jointly utilize wind energy for both higher output and higher utilization.In order to effectively implement wireless monitoring of the forest environment,the WH-EH is further utilized to develop a self-powered forest environment monitoring microsystem by powering the IoTs sensor nodes,realizing ambient temperature and humidity sampling and wireless transmission,so as to achieve the purpose of preventing forest fires.It is believed that the development of the WH-EH and the self-powered forest environment monitoring microsystem provides diverse options for the practicalization of self-powered IoTs systems and the energy supply problem of IoTs sensor networks.

关键词： self-powered nanogenerator MEMS energy harvesting microsystem

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卷对卷化学气相沉积法制备石墨烯

science china Materials 2022年第4期65卷 1042-1048页

作者：梁明昊钱凌轩侯雨婷李俊沈长青青芳竹李雪松 State Key Laboratory of electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu610054China School of electronic science and Engineering University of Electronic Science and Technology of ChinaChengdu610054China Shenzhen Institute for Advanced Study University of Electronic Science and Technology of ChinaShenzhen518110China

批到批(B2B)和卷到卷(R2R)工艺均可用于石墨烯薄膜的大规模生产.由于设备简单,B2B工艺在实验室研究中非常普遍.相对而言,R2R工艺更容易自动化,并且与随后的转移过程更兼容,因此在工业上更受青睐.目前,对R2R工艺的研究主要集中在反应器... 详细信息

批到批(B2B)和卷到卷(R2R)工艺均可用于石墨烯薄膜的大规模生产.由于设备简单,B2B工艺在实验室研究中非常普遍.相对而言,R2R工艺更容易自动化,并且与随后的转移过程更兼容,因此在工业上更受青睐.目前,对R2R工艺的研究主要集中在反应器设计或装料结构等方面,对石墨烯生长动力学缺乏深入的了解.本文通过研究石墨烯的生长演化过程,发现在相同的反应参数下,R2R工艺的石墨烯晶畴密度大于B2B工艺的石墨烯畴密度,其原因归结于两种工艺不同的反应过程;而通过延长反应时间,可以对石墨烯薄膜的缺陷进行修复.在优化的R2R工艺下,可以获得与常规B2B工艺相当的高质量石墨烯薄膜.本工作可促进石墨烯薄膜制备技术的发展.

关键词： graphene chemical vapor deposition roll to roll kinetics

A characterization study on perovskite X-ray detector performance based on a digital radiography system

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Nuclear science and Techniques 2023年第5期34卷 56-66页

作者： Yang Wang Qiong Zhang university of electronic science and technology of china Chengdu 610000China

X-ray imaging technologies such as digital radiography(DR),is an important aspect of modern non-destructive testing and medical diagnosis.Innovative flexible X-ray detector technologies have recently been proposed and are now receiving increasing attention owing to their superior material flexibility compared with traditional flat-panel detectors.This work aims to study these innovative flexible X-ray detectors in terms of their effectiveness in DR imaging,such as detection efficiency and spatial resolution.To achieve this goal,first,a Monte Carlo model was developed and calibrated to an in-lab 150 kV DR imaging system containing a flat-panel X-ray detector.Second,the validated model was updated with various types of flexible X-ray detectors to assess their performance in nearly realistic conditions.Key parameters such as the detection efficiency pertaining to the crystal material and thickness were studied and analyzed across a broader energy range up to 662 keV.Finally,the imaging performance of the different detectors was evaluated and compared to that of the flat-panel detector in the 150 kV DR imaging system.The results show that the flexible detectors such as the CsPbBr3crystal detector deliver promising performance in X-ray imaging and can be applied to a wider range of application scenarios,especially those requiring accurate detection at challenging angles.

关键词： Flexible X-ray detector DR imaging system Monte Carlo simulation

Source-less density measurement using an adaptive neutron-induced gamma correction method

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Nuclear science and Techniques 2023年第8期34卷 115-130页

作者： Qiong Zhang Yi Ge Yu-Lian Li university of electronic science and technology of china Chengdu 610000China

The use of radioactive isotopes,such as Cs-137,to measure formation density is a common practice;however,it poses high risks such as environmental contamination from lost sources.To address these challenges,the use of pulsed neutron sources for density measurements,also known as“source-less density”,has emerged as a promising alternative.By collecting gamma counts at different time gates according to the duty cycle of the pulsed sequence,the inelastic gamma component can be isolated to obtain more accurate density measurements.However,the collection of gamma rays during the neutron burst-on period often contains a proportion of capture gamma rays,which can reduce the accuracy of density measurements.This proportion can vary depending on the formation environment and neutron duty cycle.To address these challenges,an adaptive capture gamma correction method was developed for density measurements.This method distinguishes between“burst-on”and“burst-off”periods based on the gamma time spectra,and derives the capture ratio in the burst-on period by iteratively fitting the capture gamma time spectra,resulting in a more accurate net inelastic gamma.This method identifies the end of the pulse by automatically calculating the differential,and fits the capture gamma time spectra using Gaussian process regression,which considers the differences in formation attenuation caused by different environments.The method was verified through simulations with errors of below 0.025 g/cm3,demonstrating its adaptability and feasibility for use in formation density measurements.Overall,the proposed method has the potential to minimize the risks associated with radioactive isotopes and improve the accuracy of density measurements in various duty cycles and formation environments.

关键词： Neutron-induced gamma Adaptive correction Source-less density

Characteristic Mode Analysis: Application to Electromagnetic Radiation, Scattering, and Coupling Problems

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Chinese Journal of electronics 2023年第4期32卷 663-677页

作者： DENG Xuan ZHANG Di CHEN Yikai YANG Shiwen university of electronic science and technology of china

Recent years, the theory of characteristic modes has emerged as a powerful analysis technique in antenna engineering, providing a means to reveal the natural resonant properties of objects and providing a variety of modal parameters. Based on these modal parameters, advanced techniques have been developed based on the theory of characteristic modes to address a wide range of electromagnetic radiation, scattering, and coupling problems. This review provides an overview of some of the latest characteristic mode-based techniques for wideband design, circular polarization, radiation pattern control, scattering control, and mutual coupling control. In addition, future perspectives are discussed, highlighting the potential of characteristic modes for addressing even more complex electromagnetics problems.

关键词： Characteristic modes Antenna Wideband Scattering Mutual coupling