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A Single-Board Integrated Millimeter-Wave Asymmetric Full-Digital Beamforming Array for B5G/6G Applications
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作者 Qingqing Lin Jun Xu +9 位作者 Kai Chen Long Wang Wei Li Zhiqiang Yu Guangqi Yang Jianyi Zhou Zhe Chen Jixin Chen Xiaowei Zhu Wei Hong 《Engineering》 SCIE EI CAS CSCD 2024年第10期35-50,共16页
In this article,a single-board integrated millimeter-wave(mm-Wave)asymmetric full-digital beamforming(AFDBF)array is developed for beyond-fifth-generation(B5G)and sixth-generation(6G)communications.The proposed integr... In this article,a single-board integrated millimeter-wave(mm-Wave)asymmetric full-digital beamforming(AFDBF)array is developed for beyond-fifth-generation(B5G)and sixth-generation(6G)communications.The proposed integrated array effectively addresses the challenge of arranging a large number of ports in a full-digital array by designing vertical connections in a three-dimensional space and successfully integrating full-digital transmitting(Tx)and receiving(Rx)arrays independently in a single board.Unlike the traditional symmetric array,the proposed asymmetric array is composed of an 8×8 Tx array arranged in a square shape and an 8+8 Rx array arranged in an L shape.The center-to-center distance between two adjacent elements is 0.54k0 for both the Tx and Rx arrays,where k0 is the free-space wavelength at 27 GHz.The proposed AFDBF array possesses a more compact structure and lower system hardware cost and power consumption compared with conventional brick-type full-digital arrays.In addition,the energy efficiency of the proposed AFDBF array outperforms that of a hybrid beamforming array.The measurement results indicate that the operating frequency band of the proposed array is 24.25–29.50 GHz.An eight-element linear array within the Tx array can achieve a scanning angle ranging from-47°to+47°in both the azimuth and the elevation planes,and the measured scanning range of each eight-element Rx array is–45°to+45°.The measured maximum effective isotropic radiated power(EIRP)of the eight-element Tx array is 43.2 dBm at 28.0 GHz(considering the saturation point).Furthermore,the measured error vector magnitude(EVM)is less than 3%when 64-quadrature amplitude modulation(QAM)waveforms are used. 展开更多
关键词 Full-digital beamforming array Asymmetric structure Single-board integrated Beyond fifth-generation and sixthgeneration millimeter-wave communication Complex modulation Printed circuit board Vertical connection
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Co-Sharing Waveform Design for Millimeter-Wave Radar Communication Systems
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作者 Cui Gaofeng He Mengmin +2 位作者 Xu Lexi Wang Changheng Wang Weidong 《China Communications》 SCIE CSCD 2024年第6期305-318,共14页
Millimeter-wave(mmWave)radar communication has emerged as an important technique for future wireless systems.However,the interference between the radar signal and communication data is the main issue that should be co... Millimeter-wave(mmWave)radar communication has emerged as an important technique for future wireless systems.However,the interference between the radar signal and communication data is the main issue that should be considered for the joint radar communication system.In this paper,a co-sharing waveform(CSW)is proposed to achieve communication and radar sensing simultaneously.To eliminate the co-interference between the communication and sensing signal,signal splitting and processing methods for communication data demodulation and radar signal processing are given respectively.Simulation results show that the bit error rate(BER)of CSW is close to that of the pure communication waveform.Moreover,the proposed CSW can achieve better performance than the existing waveforms in terms of range and velocity estimation. 展开更多
关键词 co-sharing waveform millimeter-wave radar communication radar sensing range and velocity estimation
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Multiscale Feature Fusion for Gesture Recognition Using Commodity Millimeter-Wave Radar
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作者 Lingsheng Li Weiqing Bai Chong Han 《Computers, Materials & Continua》 SCIE EI 2024年第10期1613-1640,共28页
Gestures are one of the most natural and intuitive approach for human-computer interaction.Compared with traditional camera-based or wearable sensors-based solutions,gesture recognition using the millimeter wave radar... Gestures are one of the most natural and intuitive approach for human-computer interaction.Compared with traditional camera-based or wearable sensors-based solutions,gesture recognition using the millimeter wave radar has attracted growing attention for its characteristics of contact-free,privacy-preserving and less environmentdependence.Although there have been many recent studies on hand gesture recognition,the existing hand gesture recognition methods still have recognition accuracy and generalization ability shortcomings in shortrange applications.In this paper,we present a hand gesture recognition method named multiscale feature fusion(MSFF)to accurately identify micro hand gestures.In MSFF,not only the overall action recognition of the palm but also the subtle movements of the fingers are taken into account.Specifically,we adopt hand gesture multiangle Doppler-time and gesture trajectory range-angle map multi-feature fusion to comprehensively extract hand gesture features and fuse high-level deep neural networks to make it pay more attention to subtle finger movements.We evaluate the proposed method using data collected from 10 users and our proposed solution achieves an average recognition accuracy of 99.7%.Extensive experiments on a public mmWave gesture dataset demonstrate the superior effectiveness of the proposed system. 展开更多
关键词 Gesture recognition millimeter-wave(mmWave)radar radio frequency(RF)sensing human-computer interaction multiscale feature fusion
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Optimization and Performance Enhancement of Gesture Recognition Algorithm Based on FMCW Millimeter-Wave Radar
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作者 Zhe He Jinlong Zhou +1 位作者 Decheng Bao Renjing Gao 《Journal of Beijing Institute of Technology》 EI CAS 2024年第5期412-421,共10页
Gesture recognition plays an increasingly important role as the requirements of intelligent systems for human-computer interaction methods increase.To improve the accuracy of the millimeter-wave radar gesture detectio... Gesture recognition plays an increasingly important role as the requirements of intelligent systems for human-computer interaction methods increase.To improve the accuracy of the millimeter-wave radar gesture detection algorithm with limited computational resources,this study improves the detection performance in terms of optimized features and interference filtering.The accuracy of the algorithm is improved by refining the combination of gesture features using a self-constructed dataset,and biometric filtering is introduced to reduce the interference of inanimate object motion.Finally,experiments demonstrate the effectiveness of the proposed algorithm in both mitigating interference from inanimate objects and accurately recognizing gestures.Results show a notable 93.29%average reduction in false detections achieved through the integration of biometric filtering into the algorithm’s interpretation of target movements.Additionally,the algorithm adeptly identifies the six gestures with an average accuracy of 96.84%on embedded systems. 展开更多
关键词 gesture recognition biometric filtering frequency-modulated continuous wave(FMCW)millimeter-wave radar feature optimization human-computer interaction
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A 37 GHz Millimeter-Wave Antenna Array for 5G Communication Terminals
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作者 Jalal Khan Sadiq Ullah +3 位作者 Usman Ali Ladislau Matekovits Farooq Ahmad Tahir Muhammad Inam Abbasi 《Computers, Materials & Continua》 SCIE EI 2023年第4期1317-1330,共14页
This work presents,design and specific absorption rate(SAR)analysis of a 37GHz antenna,for 5th Generation(5G)applications.The proposed antenna comprises of 4-elements of rectangular patch and an even distribution.The ... This work presents,design and specific absorption rate(SAR)analysis of a 37GHz antenna,for 5th Generation(5G)applications.The proposed antenna comprises of 4-elements of rectangular patch and an even distribution.The radiating element is composed of copper material supported by Rogers RT5880 substrate of thickness,0.254 mm,dielectric constant(εr),2.2,and loss tangent,0.0009.The 4-elements array antenna is compact in size with a dimension of 8mm×20mm in length and width.The radiating patch is excited with a 50 ohms connector i.e.,K-type.The antenna resonates in the frequency band of 37 GHz,that covers the 5G applications.The antenna behavior is studied both in free space and in the proximity of the human body.Three models of the human body,i.e.,belly,hand,and head(contain skin,fat,muscles,and bone)are considered for on-body simulations.At resonant frequency,the antenna gives a boresight gain of 11.6 dB.The antenna radiates efficiently with a radiated efficiency of more than 90%.Also,it is observed that the antenna detunes to the lowest in the proximity of the human body,but still a good impedance matching is achieved considering the−10 dB criteria.Moreover,SAR is also being presented.The safe limit of 2 W/kg for any 10 g of biological tissue,specified by the European International Electro Technical Commission(IEC)has been considered.The calculated values of SAR for human body models,i.e.,belly,hand and head are 1.82,1.81 and 1.09 W/kg,respectively.The SAR values are less than the international recommendations for the three models.Furthermore,the simulated and measured results of the antenna are in close agreement,which makes it,a potential candidate for the fifth-generation smart phones and other handheld devices. 展开更多
关键词 5G antenna array SAR millimeter-wave smart phones
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Non-LOS target localization via millimeter-wave automotive radar
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作者 LIU Zhaoyu ZHANG Wenli +4 位作者 ZHENG Jingyue GUO Shisheng CUI Guolong KONG Lingjiang LIANG Kun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1171-1181,共11页
This paper considers the non-line-of-sight(NLOS)vehicle localization problem by using millimeter-wave(MMW)automotive radar.Several preliminary attempts for NLOS vehicle detection are carried out and achieve good resul... This paper considers the non-line-of-sight(NLOS)vehicle localization problem by using millimeter-wave(MMW)automotive radar.Several preliminary attempts for NLOS vehicle detection are carried out and achieve good results.Firstly,an electromagnetic(EM)wave NLOS multipath propagation model for vehicle scene is established.Subsequently,with the help of available multipath echoes,a complete NLOS vehicle localiza-tion algorithm is proposed.Finally,simulation and experimental results validate the effectiveness of the established EM wave propagation model and the proposed NLOS vehicle localization algorithm. 展开更多
关键词 millimeter-wave(MMW)automotive radar multipath propagation model non-line-of-sight(NLOS)vehicle localization
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Analysis and Modeling of Broadband CMOS Monolithic Balun up to Millimeter-Wave Frequencies
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作者 夏峻 王志功 +1 位作者 吴秀山 李伟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第3期467-472,共6页
The implementation of broadband monolithic baluns based on CMOS technology is investigated. The configuration and parameterized layout are analyzed. Then,a wide-band lumped element equivalent circuit model accounting ... The implementation of broadband monolithic baluns based on CMOS technology is investigated. The configuration and parameterized layout are analyzed. Then,a wide-band lumped element equivalent circuit model accounting for all necessary physical effects is proposed and model parameters are extracted, with high accuracy in a broadband frequency range ,via combination of physical formula and fitting optimization. Two baluns were implemented with TSMC's one-poly eight-metal (1P8M) 0.13μm mixed-signal (MS)/RF CMOS process. The S-parameters of these two baluns were measured using a vector network analyzer. The measured results agree well with the modeled parameters up to millimeter-wave frequencies. 展开更多
关键词 MODELING millimeter-wave CMOS
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UAV Communications with Millimeter-Wave Beamforming:Potentials,Scenarios,and Challenges 被引量:26
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作者 Zhenyu Xiao Lipeng Zhu Xiang-Gen Xia 《China Communications》 SCIE CSCD 2020年第9期147-166,共20页
Unmanned aerial vehicle(UAV)has been widely used in many fields and is arousing global attention.As the resolution of the equipped sensors in the UAV becomes higher and the tasks become more complicated,much higher da... Unmanned aerial vehicle(UAV)has been widely used in many fields and is arousing global attention.As the resolution of the equipped sensors in the UAV becomes higher and the tasks become more complicated,much higher data rate and longer communication range are required in the foreseeable future.As the millimeter-wave(mm Wave)band can provide more abundant frequency resources than the microwave band,much higher achievable rate can be guaranteed to support UAV services such as video surveillance,hotspot coverage,and emergency communications,etc.The flexible mm Wave beamforming can be used to overcome the high path loss caused by the long propagation distance.In this paper,we study three typical application scenarios for mm Wave-UAV communications,namely communication terminal,access point,and backbone link.We present several key enabling techniques for UAV communications,including beam tracking,multi-beam forming,joint Tx/Rx beam alignment,and full-duplex relay techniques.We show the coupling relation between mm Wave beamforming and UAV positioning for mm Wave-UAV communications.Lastly,we summarize the challenges and research directions of mm Wave-UAV communications in detail. 展开更多
关键词 unmanned aerial vehicle(UAV) millimeter-wave(mmWave)communications BEAMFORMING beam tracking DEPLOYMENT
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IEEE 802.11aj(45GHz):A New Very High Throughput Millimeter-Wave WLAN System 被引量:10
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作者 WANG Haiming HONG Wei +2 位作者 CHEN Jixin SUN Bo PENG Xiaoming 《China Communications》 SCIE CSCD 2014年第6期51-62,共12页
This paper presents an overview of a new very high throughput millimeterwave WLAN system operating at 45 GHz band. We begin by reviewing standards process of IEEE 802.11aj(45GHz). Then the frequency spectrum allocatio... This paper presents an overview of a new very high throughput millimeterwave WLAN system operating at 45 GHz band. We begin by reviewing standards process of IEEE 802.11aj(45GHz). Then the frequency spectrum allocation at 45 GHz band is introduced. Next, the channel measurement and mod-eling is given. Specifically, the millimeter-wave MIMO for physical layer enhancement is given in detail. 展开更多
关键词 wireless local access network(WLAN) millimeter-wave very highthroughput 45 GHz mul-tiple-input andmultiple-output (MIMO)
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Geometric Mean Decomposition Based Hybrid Precoding for Millimeter-Wave Massive MIMO 被引量:18
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作者 Tian Xie Linglong Dai +2 位作者 Xinyu Gao Muhammad Zeeshan Shakir Jianjun Li 《China Communications》 SCIE CSCD 2018年第5期229-238,共10页
Hybrid precoding can reduce the number of required radio frequency(RF)chains in millimeter-Wave(mmWave) massive MIMO systems. However, existing hybrid precoding based on singular value decomposition(SVD) requires the ... Hybrid precoding can reduce the number of required radio frequency(RF)chains in millimeter-Wave(mmWave) massive MIMO systems. However, existing hybrid precoding based on singular value decomposition(SVD) requires the complicated bit allocation to match the different signal-to-noise-ratios(SNRs) of different sub-channels. In this paper,we propose a geometric mean decomposition(GMD)-based hybrid precoding to avoid the complicated bit allocation. Specifically,we seek a pair of analog and digital precoders sufficiently close to the unconstrained fully digital GMD precoder. To achieve this, we fix the analog precoder to design the digital precoder, and vice versa. The analog precoder is designed based on the orthogonal matching pursuit(OMP) algorithm, while GMD is used to obtain the digital precoder. Simulations show that the proposed GMD-based hybrid precoding achieves better performance than the conventional SVD-based hybrid precoding with only a slight increase in complexity. 展开更多
关键词 millimeter-wave Massive MIMO hybrid precoding geometric mean decomposition bit allocation
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Millimeter-wave Exposure Promotes the Differentiation of Bone Marrow Stromal Cells into Cells with a Neural Phenotype 被引量:9
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作者 童叶青 杨朝辉 +5 位作者 杨迪 楚慧款 曲敏 刘冠兰 吴艳 刘胜洪 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第4期409-412,共4页
This study investigated the ability of millimeter-wave (MMW) to promote the differentiation of bone marrow stromal cells (BMSCs) into cells with a neural phenotype. The BMSCs were primarily cultured. At passage 3,... This study investigated the ability of millimeter-wave (MMW) to promote the differentiation of bone marrow stromal cells (BMSCs) into cells with a neural phenotype. The BMSCs were primarily cultured. At passage 3, the cells were induced by β-mercaptoethanol (BME) in combination with MMW or BME alone. The expressions of nucleostemin (NS) and neuron-specific enolase (NSE) were detected by immunofluorescent staining and Western blotting respectively to identify the differentiation. The untreated BMSCs predominately expressed NS. After induced by BME and MMW, the BMSCs exhibited a dramatic decrease in NS expression and increase in NSE expression. The differentiation rate of the cells treated with BME and MMW in combination was significantly higher than that of the cells treated with BME alone (P〈0.05). It was concluded that MMW exposure enhanced the inducing effect of BME on the differentiation of BMSCs into cells with a neural phenotype. 展开更多
关键词 bone marrow stromal cells β-mercaptoethanol millimeter-wave NUCLEOSTEMIN neuron specific enolase
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Wide-Angle Scanning Antennas for Millimeter-Wave 5G Applications 被引量:4
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作者 Raj Mittra Abdelkhalek Nasri Ravi Kumar Arya 《Engineering》 SCIE EI 2022年第4期60-71,共12页
The fifth generation(5G)network communication systems operate in the millimeter waves and are expected to provide a much higher data rate in the multi-gigabit range,which is impossible to achieve using current wireles... The fifth generation(5G)network communication systems operate in the millimeter waves and are expected to provide a much higher data rate in the multi-gigabit range,which is impossible to achieve using current wireless services,including the sub-6 GHz band.In this work,we briefly review several existing designs of millimeter-wave phased arrays for 5G applications,beginning with the low-profile antenna array designs that either are fixed beam or scan the beam only in one plane.We then move on to array systems that offer two-dimensional(2D)scan capability,which is highly desirable for a majority of 5G applications.Next,in the main body of the paper,we discuss two different strategies for designing scanning arrays,both of which circumvent the use of conventional phase shifters to achieve beam scanning.We note that it is highly desirable to search for alternatives to conventional phase shifters in the millimeter-wave range because legacy phase shifters are both lossy and costly;furthermore,alternatives such as active phase shifters,which include radio frequency amplifiers,are both expensive and power-hungry.Given this backdrop,we propose two different antenna systems with potential for the desired 2D scan performance in the millimeter-wave range.The first of these is a Luneburg lens,which is excited either by a 2D waveguide array or by a microstrip patch antenna array to realize 2D scan capability.Next,for second design,we turn to phased-array designs in which the conventional phase shifter is replaced by switchable PIN diodes or varactor diodes,inserted between radiating slots in a waveguide to provide the desired phase shifts for scanning.Finally,we discuss several approaches to enhance the gain of the array by modifying the conventional array configurations.We describe novel techniques for realizing both one-dimensional(1D)and 2D scans by using a reconfigurable metasurface type of panels. 展开更多
关键词 Luneburg lens Scanning arrays millimeter-wave antennas Switchable phase shifters Reconfigurable metasurfaces
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Automatic Identification of Clear-Air Echoes Based on Millimeter-wave Cloud Radar Measurements 被引量:3
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作者 Ling YANG Yun WANG +5 位作者 Zhongke WANG Qian YANG Xingang FAN Fa TAO Xiaoqiong ZHEN Zhipeng YANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第8期912-924,共13页
Millimeter-wave cloud radar(MMCR)provides the capability of detecting the features of micro particles inside clouds and describing the internal microphysical structure of the clouds.Therefore,MMCR has been widely appl... Millimeter-wave cloud radar(MMCR)provides the capability of detecting the features of micro particles inside clouds and describing the internal microphysical structure of the clouds.Therefore,MMCR has been widely applied in cloud observations.However,due to the influence of non-meteorological factors such as insects,the cloud observations are often contaminated by non-meteorological echoes in the clear air,known as clear-air echoes.It is of great significance to automatically identify the clear-air echoes in order to extract effective meteorological information from the complex weather background.The characteristics of clear-air echoes are studied here by combining data from four devices:an MMCR,a laser-ceilometer,an L-band radiosonde,and an all-sky camera.In addition,a new algorithm,which includes feature extraction,feature selection,and classification,is proposed to achieve the automatic identification of clear-air echoes.The results show that the recognition algorithm is fairly satisfied in both simple and complex weather conditions.The recognition accuracy can reach up to 95.86%for the simple cases when cloud echoes and clear-air echoes are separate,and 88.38%for the complicated cases when low cloud echoes and clear-air echoes are mixed. 展开更多
关键词 millimeter-wave cloud radar clear-air echoes neural network laser ceilometer all-sky camera feature extraction feature selection
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Multi-channel 28-GHz millimeter-wave signal generation on a silicon photonic chip with automated polarization control 被引量:2
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作者 Ruiyuan Cao Yu He +4 位作者 Qingming Zhu Jingchi Li Shaohua An Yong Zhang Yikai Su 《Journal of Semiconductors》 EI CAS CSCD 2019年第5期33-39,共7页
We propose and experimentally demonstrate an integrated silicon photonic scheme to generate multi-channel millimeter-wave(MMW) signals for 5 G multi-user applications. The fabricated silicon photonic chip has a footpr... We propose and experimentally demonstrate an integrated silicon photonic scheme to generate multi-channel millimeter-wave(MMW) signals for 5 G multi-user applications. The fabricated silicon photonic chip has a footprint of 1.1 × 2.1 mm^2 and integrates 7 independent channels each having on-chip polarization control and heterodyne mixing functions. 7 channels of4-Gb/s QPSK baseband signals are delivered via a 2-km multi-core fiber(MCF) and coupled into the chip with a local oscillator(LO) light. The polarization state of each signal light is automatically adjusted and aligned with that of the LO light, and then 7 channels of 28-GHz MMW carrying 4-Gb/s QPSK signals are generated by optical heterodyne beating. Automated polarizationcontrol function of each channel is also demonstrated with ~7-ms tuning time and ~27-dB extinction ratio. 展开更多
关键词 MULTI-CHANNEL millimeter-wave(MMW) generation SILICON PHOTONIC integrated circuits SILICON polarization control(SPC)
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Deep learning for fast channel estimation in millimeter-wave MIMO systems 被引量:3
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作者 LYU Siting LI Xiaohui +2 位作者 FAN Tao LIU Jiawen SHI Mingli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第6期1088-1095,共8页
Channel estimation has been considered as a key issue in the millimeter-wave(mmWave)massive multi-input multioutput(MIMO)communication systems,which becomes more challenging with a large number of antennas.In this pap... Channel estimation has been considered as a key issue in the millimeter-wave(mmWave)massive multi-input multioutput(MIMO)communication systems,which becomes more challenging with a large number of antennas.In this paper,we propose a deep learning(DL)-based fast channel estimation method for mmWave massive MIMO systems.The proposed method can directly and effectively estimate channel state information(CSI)from received data without performing pilot signals estimate in advance,which simplifies the estimation process.Specifically,we develop a convolutional neural network(CNN)-based channel estimation network for the case of dimensional mismatch of input and output data,subsequently denoted as channel(H)neural network(HNN).It can quickly estimate the channel information by learning the inherent characteristics of the received data and the relationship between the received data and the channel,while the dimension of the received data is much smaller than the channel matrix.Simulation results show that the proposed HNN can gain better channel estimation accuracy compared with existing schemes. 展开更多
关键词 millimeter-wave(mmWave) channel estimation deep learning(DL) dimensional mismatch channel state information(CSI)
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Roles of rare earth oxide additives in millimeter-wave sintering of AlN 被引量:2
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作者 Yukio Makino Takashi Yoshioka +2 位作者 Hiromi Nakano Toshiyuki Ueno Shoji Miyake 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期141-145,共5页
Roles of rare earth oxide (RE2O3) additives in millimeter-wave(MM) sintering of AIN were investigated from the standpoints of phase diagram, heating characteristics of rare earth oxides, and morphology of intergra... Roles of rare earth oxide (RE2O3) additives in millimeter-wave(MM) sintering of AIN were investigated from the standpoints of phase diagram, heating characteristics of rare earth oxides, and morphology of intergranular oxide phase. In the millimeter-wave sintering of AIN, densification temperature decreased with the decrease of the ionic radius of rare earth ion and was closely related with the eutectic temperature in the RE2Oa-Al2O3 binary system. The lowest densification temperature in the millimeter-wave sintering of AIN with Yb2O3 additive was attributed to the largest heating rate of Yb2O3-Al2O3 binary oxide under millimeter-wave radiation. Furthermore, the lowest densification temperature could be attained while selecting the Yb2O3 content so as to form the intergranular phase with the eutectic composition in the Yb2O3-Al2O3 binary system. The result showed good agreement with the above mentioned during the sintering of Si3N4 with Yb2O3-Al2O3 additive. From TEM observation, it was verified that film-like intergranular oxide phase formed under millimeter-wave radiation was favorable for attaining high thermal conductivity in the Yb2O3 added AINs. 展开更多
关键词 millimeter-wave rare earth oxide AIN Si3N4 rapid densification selective heating heating rate thermal conductivity morphology
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Improvement of breakdown characteristics of an A1GaN/GaN HEMT with a U-type gate foot for millimeter-wave power application 被引量:1
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作者 孔欣 魏珂 +1 位作者 刘果果 刘新宇 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期531-537,共7页
In this study, the physics-based device simulation tool Silvaco ATLAS is used to characterize the electrical properties of an AlGaN/GaN high electron mobility transistor (HEMT) with a U-type gate foot. The U-gate Al... In this study, the physics-based device simulation tool Silvaco ATLAS is used to characterize the electrical properties of an AlGaN/GaN high electron mobility transistor (HEMT) with a U-type gate foot. The U-gate AlGaN/GaN HEMT mainly features a gradually changed sidewall angle, which effectively mitigates the electric field in the channel, thus obtaining enhanced off-state breakdown characteristics. At the same time, only a small additional gate capacitance and decreased gate resistance ensure excellent RF characteristics for the U-gate device. U-gate AlGaN/GaN HEMTs are feasible through adjusting the etching conditions of an inductively coupled plasma system, without introducing any extra process steps. The simulation results are confirmed by experimental measurements. These features indicate that U-gate A1GaN/GaN HEMTs might be promising candidates for use in millimeter-wave power applications. 展开更多
关键词 AlGaN/GaN HEMT breakdown characteristics millimeter-wave U-type gate foot
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A Novel Millimeter-Wave Channel Measurement Platform for 6G Intelligent Railway Scenarios 被引量:1
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作者 Dan Fei Chen Chen +4 位作者 Peng Zheng Dongsheng Zhang Jingya Yang Haoran Chen Bo Ai 《China Communications》 SCIE CSCD 2022年第11期60-73,共14页
This paper presented a novel millimeterwave channel measurement platform for the 6G intelligent railway.This platform used phased array antenna with 64 elements and can support instant bandwidth up to 1 GHz.Combined w... This paper presented a novel millimeterwave channel measurement platform for the 6G intelligent railway.This platform used phased array antenna with 64 elements and can support instant bandwidth up to 1 GHz.Combined with improved multi-tone sounding signals,the platform can enhance dynamic measurement capability in high-speed railway scenarios.We performed calibration works about frequency flatness,frequency offset and proved platform reliability with channel emulator based closed-loop verification.We also carried out field trials in high-speed railway carriage scenarios.Based on measurement results,we extracted channel characteristic parameters of path loss,power delay profile and delay spread to further verify the field measurement performance of the platform. 展开更多
关键词 6G millimeter-wave channel measurement phased array antenna high-speed railway
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Towards Converged Millimeter-Wave/Terahertz Wireless Communication and Radar Sensing 被引量:2
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作者 GAO Xiang Saqlain MUHAMMAD +4 位作者 CAO Xiaoxiao WANG Shiwei LIU Kexin ZHANG Hangkai YU Xianbin 《ZTE Communications》 2020年第1期73-82,共10页
Converged communication and radar sensing systems have attained increasing attention in recent years.The development of converged radar-data systems is reviewed,with a special focus on millimeter/terahertz systems as ... Converged communication and radar sensing systems have attained increasing attention in recent years.The development of converged radar-data systems is reviewed,with a special focus on millimeter/terahertz systems as a promising trend.Firstly,we present historical development and convergence technology concept for communication-radar systems,and highlight some emerging technologies in this area.We then provide an updated and comprehensive survey of several converged systems operating in different microwave and millimeter frequency bands,by providing some selective typical communication and radar sensing systems.In this part,we also summarize and compare the system performance in terms of maximum range/range resolution for radar mode and Bit Error Rate(BER)/wireless distance for communication mode.In the last section,the convergence of millimeter/terahertz communication-radar system is concluded by analyzing the prospect of millimeter-wave/terahertz technologies in providing ultrafast data rates and high resolution for our smart future. 展开更多
关键词 system convergence wireless communication radar sensing millimeter-wave TERAHERTZ
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Millimeter-wave LFMCW radar water surface detection experiment and its imaging algorithm 被引量:1
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作者 CHONG Jin-song WEI Xiang-fei 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2017年第1期46-53,共8页
A millimeter-wave linear frequency modulated continuous wave(LFM CW)radar is applied to water surface detection.This paper presents the experiment and imaging algorithm.In imaging processing,water surface texture can ... A millimeter-wave linear frequency modulated continuous wave(LFM CW)radar is applied to water surface detection.This paper presents the experiment and imaging algorithm.In imaging processing,water surface texture can hardly be seen in the results obtained by traditional imaging algorithm.To solve this problem,we propose a millimeter-wave LFMCW radar imaging algorithm for water surface texture.Different from the traditional imaging algorithm,the proposed imaging algorithm includes two improvements as follows:Firstly,the interference from static targets is removed through a frequency domainfilter;Secondly,the multiplicative noises are reduced by the maximum likelihood estimation method,which is used to estimatethe azimuth spectrum parameters to calculate the energy of water surface echo.Final results show that the proposed algorithmcan obtain water surface texture,which means that the proposed algorithm is superior to the traditional imaging algorithm. 展开更多
关键词 millimeter-wave LFMCW radar water surface texture imaging algorithm maximum likelihood estimation
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