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Beam squint effect on high-throughput millimeter-wave communication with an ultra-massive phased array

Zhiqiang Wang, Jiawei Liu, Jun Wang, Guangrong Yue,wangzq@std.uestc.edu.cn,842927584@qq.com,junwang@uestc.edu.cn,yuegr@uestc.edu.cn

Frontiers of Information Technology & Electronic Engineering 2021, Volume 22, Issue 4,   Pages 560-570 doi: 10.1631/FITEE.2000451

Abstract: An can be deployed in high-throughput communication systems to increase the transmission distance. However, when the signal bandwidth is large, the antenna array response changes with the frequency, causing . In this paper, we investigate the effect on a high-throughput mmWave communication system with the single-carrier frequency-domain equalization transmission scheme. Specifically, we first view analog beamforming and the physical channel as a spatial equivalent channel. The characteristics of the spatial equivalent channel are analyzed which behaves like frequency-selective fading. To eliminate the deep fading points in the spatial equivalent channel, an advanced analog beamforming method is proposed based on the (ZC) sequence. Then, the low-complexity linear zero-forcing and minimum mean squared error equalizers are considered at the receiver. Simulation results indicate that the proposed ZC-based analog beamforming method can effectively mitigate the performance loss by the .

Keywords: 超大规模相控阵;毫米波;波束倾斜;Zadoff-Chu;单载波频域均衡    

Research on the Impact of Mining in Steep Seam on Ground Struc ture

Gao Mingzhong,Wang Lieping

Strategic Study of CAE 2007, Volume 9, Issue 11,   Pages 142-146

Abstract:

According to the complex geologic condition of deep excavat ion in Huainan, probability-integral method is ewployed to study the for surface displacement due to coal extraction by optimization mining layouts.  Correlation parameters about subsidence under thick loose overburden and duplication mining are obtained. The results obtained may provide guidance for the subsidence-administrating. It is valuable of this paper to other coal mines which have similar geological and mining conditions.

Keywords: steep seam     surface movement and deformation     probability-integral method     predictions    

Dot-shaped beamforming analysis of subarray-based sin-FDA Research Article

Bo Wang, Jun-wei Xie, Jing Zhang, Jia-ang Ge,wb_wangbo1991@163.com

Frontiers of Information Technology & Electronic Engineering 2019, Volume 20, Issue 10,   Pages 1429-1444 doi: 10.1631/FITEE.1800722

Abstract: Phased array (PA) radar is one of the most popular types of radar. In contrast to PA, the (FDA) is a potential solution to suppress range-related interference because of its time-range-angle-dependent beampattern. However, the range-angle coupling inherent in the FDA transmit beampattern may degrade the output signal-to-interference-plus-noise ratio (SINR). We propose a method based on the analyzed four subarray-based FDAs and subarray-based planar FDAs using a sinusoidally increasing frequency offset with elements transmitting at multiple frequencies. The numerical results show that the proposed approach outperforms the existing log-FDA with logarithmical frequency offset in transmit energy focus, sidelobe suppression, and array resolution. Comparative simulation results validate the effectiveness of the proposed method.

Keywords: 频率分集阵列;子阵频率分集阵列;解耦;点状波束形成    

Miniaturized Rotman lens with applications to wireless communication Research Articles

Bao-hua SUN, Qiu-yan LIANG, Gao-nan ZHOU

Frontiers of Information Technology & Electronic Engineering 2020, Volume 21, Issue 1,   Pages 144-158 doi: 10.1631/FITEE.1900501

Abstract: Rotman lens is a type of beamforming network with many advantages, such as true-time delay characteristic, multibeam capability, and wide bandwidth. Rotman lens has been used in a wide range of applications in today’s wireless communication systems. However, the size of a conventional Rotman lens is considerably large. So, difficulties may arise with respect to its integration with base station antennas in wireless communication systems. In this study, three techniques for the miniaturization of a Rotman lens, i.e., Chebyshev impedance transformers, power dividers, and truncated ports with energy distribution slots, are introduced to design the Rotman lens to reduce the size of the ports and hence the total area occupied by the Rotman lens. Simulation and measurement results indicate that good impedance matching between the lens body and its feed lines can be achieved. Using the proposed truncated ports with energy distribution slots, the size of the Rotman lens can be greatly reduced without performance degradation or production cost increment. Moreover, two possible applications of the proposed miniaturized Rotman lens to wireless communication systems are investigated. Rotman lens can not only provide multiple phase difference signals along the array ports to realize multibeams, but also generate high-performance formed beams such as flat-topped radiation pattern.

Keywords: Rotman lens     Miniaturization     Multibeam     Beamformer     Wireless communication    

Beamforming and fronthaul compression design for intelligent reflecting surface aided cloud radio access networks Research Article

Yu ZHANG, Xuelu WU, Hong PENG, Caijun ZHONG, Xiaoming CHEN,yzhang@zjut.edu.cn,ph@zjut.edu.cn,caijunzhong@zju.edu.cn,chen_xiaoming@zju.edu.cn

Frontiers of Information Technology & Electronic Engineering 2022, Volume 23, Issue 1,   Pages 31-46 doi: 10.1631/FITEE.2100307

Abstract: Owing to the inherent central information processing and resource management ability, the is a promising network structure for an intelligent and simplified sixth-generation (6G) wireless network. Nevertheless, to further enhance the capacity and coverage, more radio remote heads (RRHs) as well as high-fidelity and low-latency fronthaul links are required, which may lead to high implementation cost. To address this issue, we propose to exploit the as an alternative way to enhance the C-RAN, which is a low-cost and energy-efficient option. Specifically, we consider the uplink transmission where multi-antenna users communicate with the baseband unit (BBU) pool through multi-antenna RRHs and multiple IRSs are deployed between the users and RRHs. RRHs can conduct either point-to-point (P2P) compression or Wyner-Ziv coding to compress the received signals, which are then forwarded to the BBU pool through fronthaul links. We investigate the joint design and optimization of user transmit beamformers, IRS passive beamformers, and noise covariance matrices to maximize the uplink sum rate subject to fronthaul capacity constraints under P2P compression and Wyner-Ziv coding. By exploiting the Arimoto-Blahut algorithm and semi-definite relaxation (SDR), we propose a successive convex approximation approach to solve non-convex problems, and two iterative algorithms corresponding to P2P compression and Wyner-Ziv coding are provided. Numerical results verify the performance gain brought about by deploying IRS in C-RAN and the superiority of the proposed joint design.

Keywords: Cloud radio access network (C-RAN)     Intelligent reflecting surface (IRS)     Transmit beamforming     Fronthaul compression    

A 39 GHz Dual-Channel Transceiver Chipset With an Advanced LTCC Package for 5G Multi-Beam MIMO Systems Aticle

Yiming Yu,Zhilin Chen,Chenxi Zhao,Huihua Liu,Yunqiu Wu,Wen-Yan Yin,Kai Kang

Engineering 2023, Volume 22, Issue 3,   Pages 125-140 doi: 10.1016/j.eng.2022.04.023

Abstract:

This article presents a 39 GHz transceiver front-end chipset for 5G multi-input multi-output (MIMO) applications. Each chip includes two variable-gain frequency-conversion channels and can support two simultaneous independent beams, and the chips also integrate a local-oscillator chain and digital module for multi-chip extension and gain-state control. To improve the radio-frequency performance, several circuit-level improvement techniques are proposed for the key building blocks in the front-end system. Furthermore, an advanced low-temperature co-fired ceramic process is developed to package the 39 GHz dual-channel transceiver chipset, and it achieves low packaging loss and high isolation between the two transmitting (TX)/receiving (RX) channels. Both the chip-level and system-in-package (SIP)-level measurements are conducted to demonstrate the performance of the transceiver chipset. The measurement characteristics show that the TX SIP provides 11 dB maximum gain and 10 dBm saturated output power, while the RX SIP achieves 52 dB maximum gain, 5.4 dB noise figure, and 7.2 dBm output 1 dB compression point. Single-channel communication link testing of the transceiver exhibits an error vector magnitude (EVM) of 3.72% and a spectral efficiency of 3.25 bit·s−1·Hz−1 for 64-quadrature amplitude modulation (QAM) modulation and an EVM of 3.76% and spectral efficiency of 3.9 bit·s−1·Hz−1 for 256-QAM modulation over a 1 m distance. Based on the chipset, a 39 GHz multi-beam prototype is also developed to perform the MIMO operation for 5G millimetre wave applications. The over-the-air communication link for one- and two-stream transmission indicates that the multi-beam prototype can cover a 5–150 m distance with comparable throughput.

Keywords: 5G     Multi-beam     Multi-input multi-output     Millimeter-wave     Transceiver     Wireless communication    

Modeling of a dynamic dual-input dual-output fast steeringmirror system Article

Hong SONG, Jia-heng ZHANG, Ping YANG, Hao-cai HUANG, Shu-yue ZHAN, Teng-jun LIU, Yi-lu GUO, Hang-zhou WANG, Hui HUANG, Quan-quan MU, Mei-fen FANG, Ming-yuan YANG

Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 10,   Pages 1488-1498 doi: 10.1631/FITEE.1601221

Abstract: A modeling method is proposed for a dynamic fast steering mirror (FSM) system with dual inputs and dual outputs. A physical model of the FSM system is derived based on first principles, describing the dynamics and coupling between the inputs and outputs of the FSM system. The physical model is then represented in a state-space form. Unknown parameters in the state-space model are identified by the subspace identification algorithm, based on the measured input-output data of the FSM system. The accuracy of the state-space model is evaluated by comparing the model estimates with measurements. The variance-accounted-for value of the state-space model is better than 97%, not only for the modeling data but also for the validation data set, indicating high accuracy of the model. Comparison is also made between the proposed dynamic model and the conventional static model, where improvement in model accuracy is clearly observed. The model identified by the proposed method can be used for optimal controller design for closed-loop FSM systems. The modeling method is also applicable to FSM systems with similar structures.

Keywords: Fast steering mirror     Dynamic system     Input-output coupling     Physical modeling     Subspace identification    

Optimal Design of Aperture Illuminations for Microwave Power Transmission with Annular Collection Areas Article

Xun Li, Baoyan Duan, Yiqun Zhang, Yongxin Guo

Engineering 2023, Volume 30, Issue 11,   Pages 63-74 doi: 10.1016/j.eng.2023.07.016

Abstract:

This work presents an optimal design method of antenna aperture illumination for microwave power transmission with an annular collection area. The objective is to maximize the ratio of the power radiated on the annular collection area to the total transmitted power. By formulating the aperture amplitude distribution through a summation of a special set of series, the optimal design problem can be reduced to
finding the maximum ratio of two real quadratic forms. Based on the theory of matrices, the solution to the formulated optimization problem is to determine the largest characteristic value and its associated characteristic vector. To meet security requirements, the peak radiation levels outside the receiving area are considered to be extra constraints. A hybrid grey wolf optimizer and Nelder–Mead simplex method is developed to deal with this constrained optimization problem. In order to demonstrate the effectiveness of the proposed method, numerical experiments on continuous apertures are conducted; then, discrete arrays of isotropic elements are employed to validate the correctness of the optimized results. Finally, patch arrays are adopted to further verify the validity of the proposed method.

Keywords: Microwave power transmission     Beam collection efficiency     Ring-shaped beam     Annular collection area     Grey wolf optimizer     Nelder–Mead simplex method    

Deceptive jamming discrimination based on range-anglelocalization of a frequency diverse array Article

Zhao-jian ZHANG, Jun-wei XIE, Chuan SHENG, Zhun TANG

Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 9,   Pages 1437-1446 doi: 10.1631/FITEE.1601577

Abstract: We propose a method to suppress deceptive jamming by frequencydiverse array (FDA) in radar electronic countermeasure environments.FDA offers a new range-angle-dependent beam pattern through a smallfrequency increment across elements. Due to the coupling between theangle and range, a mismatch between the test angle and physical angleoccurs when the slant range on which the beam focuses is not equalto the slant range of the real target. In addition, the range of thetarget can be extracted by sum-difference beam except for time-delaytesting, because the beam provides a range resolution in the FDA thatcannot be deceived by traditional deceptive jamming. A strategy ofusing FDA to transmit two pulses with zero and nonzero frequency increments,respectively, is proposed to ensure that the angle of a target canbe obtained by FDA. Moreover, the localization performance is examinedby analyzing the Cramer-Rao lower bound and detection probability.Effectiveness of the proposed method is confirmed by simulation results.

Keywords: Frequency diverse array (FDA)     Deceptive jamming     Range-angle coupling     Sum-difference beam     Double-pulse    

Optimization of a robust collaborative-relay beamforming design for simultaneous wireless information and power transfer None

Lu-lu ZHAO, Xing-long JIANG, Li-min LI, Guo-qiang ZENG, Hui-jie LIU

Frontiers of Information Technology & Electronic Engineering 2018, Volume 19, Issue 11,   Pages 1432-1443 doi: 10.1631/FITEE.1601268

Abstract:

We investigate a collaborative-relay beamforming design for simultaneous wireless information and power transfer. A non-robust beamforming design that assumes availability of perfect channel state information (CSI) in the relay nodes is addressed. In practical scenarios, CSI errors are usually inevitable; therefore, a robust collaborativerelay beamforming design is proposed. By applying the bisection method and the semidefinite relaxation (SDR) technique, the non-convex optimization problems of both non-robust and robust beamforming designs can be solved. Moreover, the solution returned by the SDR technique may not always be rank-one; thus, an iterative sub-gradient method is presented to acquire the rank-one solution. Simulation results show that under an imperfect CSI case, the proposed robust beamforming design can obtain a better performance than the non-robust one.

Keywords: Simultaneous wireless information and power transfer     Channel state information     Robust beamforming     Semidefinite relaxation     Iterative sub-gradient    

Wideband circular-polarized transmitarray for generating a high-purity vortex beam Correspondence

Liangjie QIU, Xiuping LI, Zihang QI, Wenyu ZHAO, Yuhan HUANG,xpli@bupt.edu.cn

Frontiers of Information Technology & Electronic Engineering 2023, Volume 24, Issue 6,   Pages 927-934 doi: 10.1631/FITEE.2200539

Abstract: In this correspondence, a wideband circular-polarized (CP) transmitarray (TA) in the Ka-band is presented for generating a high-purity vortex beam. The proposed element is composed of two identical combinations separated by an air layer. The subwavelength structure and double-resonance characteristics ensure the stable phase shift of the element within the 1-dB transmission bandwidth of 28.4%. A square aperture TA fed by a horn antenna is fabricated and measured. Owing to the honeycomb arrangement of elements, the mode purity of l​​=​​−1 is >0.93 in a wide band from 28.5 to 38 GHz. The measured peak gain is 22.3 dBic, and the 3-dB axial ratio bandwidth is 27.6%. The performance of the proposed antenna demonstrates its potential for high-capacity wireless communication and high-quality radar imaging.

Keywords: 轨道角动量;涡旋波束;透射阵;宽带;高纯度    

An array of two periodic leaky-wave antennas with sum and difference beam scanning for application in target detection and tracking Research Article

Mianfeng HUANG, Juhua LIU,liujh33@mail.sysu.edu.cn

Frontiers of Information Technology & Electronic Engineering 2023, Volume 24, Issue 4,   Pages 567-581 doi: 10.1631/FITEE.2200473

Abstract: An array of two periodic leaky-wave s (LWAs) with scanning is proposed for application in . The array is composed of two periodic LWAs with different periods, in which each LWA generates a narrow beam through the =-1 space harmonic. Due to the two different periods for the two LWAs, two beams with two different directions can be realized, which can be combined into a sum beam when the array is fed in phase or into a difference beam when the array is fed 180° out of phase. The array integrated with 180° hybrid is designed, fabricated, and measured. Measurement results show that the sum beam can reach a gain up to 15.9 dBi and scan from -33.4° to 20.8°. In the scanning range, the direction of the null in the difference beam is consistent with the direction of the sum beam, with the lowest null depth of -40.8 dB. With the excellent performance, the provides an alternative solution with low complexity and low cost for .

Keywords: Antenna     Leaky-wave antenna (LWA)     Substrate-integrated waveguide (SIW)     Sum and difference beam     Target detection and tracking    

Correspondence: A low-profile dual-polarization programmable dual-beam scanning antenna array Perspective

Shichao ZHU, Yuanfan NING, Hongbo CHU, Pei XIAO, Gaosheng LI,Gaosheng7070@vip.163.com

Frontiers of Information Technology & Electronic Engineering 2023, Volume 24, Issue 10,   Pages 1504-1512 doi: 10.1631/FITEE.2300253

Abstract: A low-profile dual-polarization dual-beam scanning antenna array based on holographic control theory is presented in this paper. The radiating elements are ingeniously designed to achieve reconfigurable polarization and modulation of the radiation phase by controlling the state of the PIN diodes integrated on each element. A 72-channel series-parallel equal-amplitude and in-phase feeding network is integrated with the radiating array to achieve low-profile characteristics. The two-dimensional (2D) dynamic and accurate deflection of the beam is achieved by a designed direct current (DC) bias circuit that digitally encodes the antenna array using the single-chip microcontroller. A 2-element subarray and a 6×12 array have been fabricated and the digitally controllable radiation pattern of this antenna system has been experimentally verified. The antenna system can achieve the beam scanning of -30° to 30° with a step-scan of 5° at 11 GHz. The proposed antenna system is characterized by low profile, low cost, easy integration, and accurate beam steering, and holds broad application prospects in radar systems, smart antennas, and other fields.

On Differentiation Among Pilot Signals of Multiple Mobile Targets in Retro-Reflective Beamforming for Wireless Power Transmission Article

Xin Wang, Long Li, Tie Jun Cui, Mingyu Lu

Engineering 2023, Volume 30, Issue 11,   Pages 55-62 doi: 10.1016/j.eng.2023.08.010

Abstract:

An experimental study is conducted on several retro-reflective beamforming schemes for wireless power transmission to multiple wireless power receivers (referred to herein as "targets"). The experimental results demonstrate that, when multiple targets broadcast continuous-wave pilot signals at respective frequencies, a retro-reflective wireless power transmitter is capable of generating multiple wireless power beams aiming at the respective targets as long as the multiple pilot signals are explicitly separated from one another by the wireless power transmitter. However, various practical complications are identified when the pilot signals of multiple targets are not appropriately differentiated from each other by the wireless power transmitter. Specifically, when multiple pilot signals are considered to be carried by the same frequency, the wireless power transmission performance becomes heavily dependent on the interaction among the pilot signals, which is highly undesirable in practice. In conclusion, it is essential for a retro-reflective wireless power transmitter to explicitly discriminate multiple targets' pilot signals among each other.

Keywords: Wireless power transmission     Microwave antenna array     Retro-reflective beamforming     Pilot signal     Multiple access    

Optimal design of a large dual-polarization microstrip reflectarray with China-coverage patterns for satellite communications Research Articles

Gang ZHAO, Yong-chang JIAO, Guan-tao CHEN

Frontiers of Information Technology & Electronic Engineering 2020, Volume 21, Issue 1,   Pages 159-173 doi: 10.1631/FITEE.1900496

Abstract: A large dual-polarization microstrip reflectarray with China-coverage patterns in two operating bands is designed. To sufficiently compensate for the spatial phase delay differences in two operating bands separately, a three-layer rectangular patch element is addressed, which is suitable for the large dual-polarization reflectarray. Due to the complexly shaped areas and high gain requirements, there are more than 25 000 elements in the reflectarray, making it difficult to design, due to more than 150 000 optimization variables. First, the discrete fast Fourier transform (DFFT) and the inverse DFFT are used to establish a one-to-one relationship between the aperture distribution and the far field, which lays a foundation for optimizing the shaped-beam reflectarray. The intersection approach, based on the alternating projection, is used to obtain the desired reflection phases of all the elements at some sample frequencies, and a new method for producing a suitable initial solution is proposed to avoid undesired local minima. To validate the design method, a dual-polarization shaped-beam reflectarray with 7569 elements is fabricated and measured. The measurement results are in reasonable agreement with the simulation ones. Then, for the large broadband reflectarray with the minimum differential spatial phase delays in the operating band, an approach for determining the optimal position of the feed is discussed. To simultaneously find optimal dimensions of each element in two orthogonal directions, we establish a new optimization model, which is solved by the regular polyhedron method. Finally, a dual-band dual-polarization microstrip reflectarray with 25 305 elements is designed to cover the continent of China. Simulation results show that patterns of the reflectarray meet the China-coverage requirements in two operating bands, and that the proposed optimization method for designing large reflectarrays with complexly shaped patterns is reliable and efficient.

Keywords: Reflectarray     Dual-polarization     Shaped beam     Phase-only synthesis    

Title Author Date Type Operation

Beam squint effect on high-throughput millimeter-wave communication with an ultra-massive phased array

Zhiqiang Wang, Jiawei Liu, Jun Wang, Guangrong Yue,wangzq@std.uestc.edu.cn,842927584@qq.com,junwang@uestc.edu.cn,yuegr@uestc.edu.cn

Journal Article

Research on the Impact of Mining in Steep Seam on Ground Struc ture

Gao Mingzhong,Wang Lieping

Journal Article

Dot-shaped beamforming analysis of subarray-based sin-FDA

Bo Wang, Jun-wei Xie, Jing Zhang, Jia-ang Ge,wb_wangbo1991@163.com

Journal Article

Miniaturized Rotman lens with applications to wireless communication

Bao-hua SUN, Qiu-yan LIANG, Gao-nan ZHOU

Journal Article

Beamforming and fronthaul compression design for intelligent reflecting surface aided cloud radio access networks

Yu ZHANG, Xuelu WU, Hong PENG, Caijun ZHONG, Xiaoming CHEN,yzhang@zjut.edu.cn,ph@zjut.edu.cn,caijunzhong@zju.edu.cn,chen_xiaoming@zju.edu.cn

Journal Article

A 39 GHz Dual-Channel Transceiver Chipset With an Advanced LTCC Package for 5G Multi-Beam MIMO Systems

Yiming Yu,Zhilin Chen,Chenxi Zhao,Huihua Liu,Yunqiu Wu,Wen-Yan Yin,Kai Kang

Journal Article

Modeling of a dynamic dual-input dual-output fast steeringmirror system

Hong SONG, Jia-heng ZHANG, Ping YANG, Hao-cai HUANG, Shu-yue ZHAN, Teng-jun LIU, Yi-lu GUO, Hang-zhou WANG, Hui HUANG, Quan-quan MU, Mei-fen FANG, Ming-yuan YANG

Journal Article

Optimal Design of Aperture Illuminations for Microwave Power Transmission with Annular Collection Areas

Xun Li, Baoyan Duan, Yiqun Zhang, Yongxin Guo

Journal Article

Deceptive jamming discrimination based on range-anglelocalization of a frequency diverse array

Zhao-jian ZHANG, Jun-wei XIE, Chuan SHENG, Zhun TANG

Journal Article

Optimization of a robust collaborative-relay beamforming design for simultaneous wireless information and power transfer

Lu-lu ZHAO, Xing-long JIANG, Li-min LI, Guo-qiang ZENG, Hui-jie LIU

Journal Article

Wideband circular-polarized transmitarray for generating a high-purity vortex beam

Liangjie QIU, Xiuping LI, Zihang QI, Wenyu ZHAO, Yuhan HUANG,xpli@bupt.edu.cn

Journal Article

An array of two periodic leaky-wave antennas with sum and difference beam scanning for application in target detection and tracking

Mianfeng HUANG, Juhua LIU,liujh33@mail.sysu.edu.cn

Journal Article

Correspondence: A low-profile dual-polarization programmable dual-beam scanning antenna array

Shichao ZHU, Yuanfan NING, Hongbo CHU, Pei XIAO, Gaosheng LI,Gaosheng7070@vip.163.com

Journal Article

On Differentiation Among Pilot Signals of Multiple Mobile Targets in Retro-Reflective Beamforming for Wireless Power Transmission

Xin Wang, Long Li, Tie Jun Cui, Mingyu Lu

Journal Article

Optimal design of a large dual-polarization microstrip reflectarray with China-coverage patterns for satellite communications

Gang ZHAO, Yong-chang JIAO, Guan-tao CHEN

Journal Article