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Beam Tracking Method Using Unscented Kalman Filter for UAV-Enabled NR MIMO- OFDM System with Hybrid Beamforming

KSII TRANSACTIONS ON INTERNET AND INFORMATION SYSTEMS 2023年第1期17卷 280-294页

作者： Sim, Yuna Sin, Seungseok Cho, Jihun Moon, Sangmi You, Young-Hwan Kim, Cheol Hong Hwang, Intae Chonnam Natl Univ Dept ICT Convergence Syst Engn 77 Yongbong Ro Gwangju 61186 South Korea Chonnam Natl Univ Sch Elect & Comp Engn 77 Yongbong Ro Gwangju 61186 South Korea Korea Nazarene Univ Dept IT Artificial Intelligence Wolbong Ro 48 Cheonan 31172 Choongcheongnam South Korea Sejong Univ Dept Comp Engn 209 Neungdong Ro Seoul 05006 South Korea Soongsil Univ Sch Comp Sci & Engn 369 Sangdo Ro Seoul 06978 South Korea Chonnam Natl Univ Coll Engn Dept Elect Engn 77 Yongbong Ro Gwangju 61186 South Korea Chonnam Natl Univ Coll Engn Dept ICT Convergence Syst Engn 77 Yongbong Ro Gwangju 61186 South Korea

Unmanned aerial vehicles (UAVs) and millimeter-wave frequencies play key roles in supporting 5G wireless communication systems. They expand the field of wireless communication by increasing the data capacities of communication systems and supporting high data rates. However, short wavelengths, owing to the high millimeter-wave frequencies can cause problems, such as signal attenuation and path loss. To address these limitations, research on high directional beamforming technologies continue to garner interest. Furthermore, owing to the mobility of the UAVs, it is essential to track the beam angle accurately to obtain full beamforming gain. This study presents a beam tracking method based on the unscented Kalman filter using hybrid beamforming. The simulation results reveal that the proposed beam tracking scheme improves the overall performance in terms of the mean -squared error and spectral efficiency. In addition, by expanding analog beamforming to hybrid beamforming, the proposed algorithm can be used even in multi-user and multi-stream environments to increase data capacity, thereby increasing utilization in new-radio multiple -input multiple-output orthogonal frequency-division multiplexing systems.

关键词： Beam tracking hybrid beamforming multiple-input multiple-output orthogonal frequency diversity multiplexing unscented Kalman filter

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Multi-Dimensional Space-Time Shift Keying for Wireless Communications

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IEEE ACCESS 2019年 7卷 135801-135811页

作者： Zheng, Guangtao Jiang, Ming Sun Yat Sen Univ Sch Elect & Informat Technol Guangzhou 510275 Peoples R China Univ Virginia Dept Comp Sci Charlottesville VA 22903 USA

In this paper, we introduce the concept of multi-dimensional (MD) space-time shift keying (STSK) for improving conventional STSK schemes, while still maintaining the general STSK structure for backward compatibility. Firstly, we design two transmission modes for three-dimensional (3-D) STSK schemes, referred to as R2 3-D STSK and R3 3-D STSK, with the incorporation of 3-D constellations. In addition, we devise a joint optimization mechanism utilizing the modified simplified conjugate gradient (SCG) algorithm to enhance the achievable system performance of R3 3-D STSK, through a harmonized design of the constellation and the dispersion matrix set. Furthermore, we derive the optimal combinations of the 3-D constellation coordinates for R2 3-D STSK by maximizing the minimal determinant of the difference matrices. Then, we extend 3-D STSK to the MD STSK family, offering a flexible and efficient performance enhancement mechanism for STSK systems. Extensive simulation results are provided to show the tradeoffs among link performance, diversity order and signal dimensionality of the proposed MD STSK scheme, illustrating a good way to upgrade conventional STSK systems.

关键词： Optimization Wireless communication Dispersion MIMO communication Research and development Simulation Modulation Coordinate combination joint optimization multi-dimensional constellation multiple-input multiple-output space-time shift keying

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Modeling of Transmission Functions and Crosstalk in Metallic Cables for Implementation of MIMO Concept

Modeling of Transmission Functions and Crosstalk in Metallic...

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作者： Lafata, P. Brno University of Technology

The new promising wireless networks based on multi-carrier modulations (MCM) and multiple-input multiple-output concept (MIMO) will soon offer high-speed digital connections. Their access points are mostly connected by fixed metallic lines to core data and telecommunication networks. That is why it will also be necessary to increase the transmission speed and overall performance of these fixed access networks adequately in order to meet the expected requirements of wireless connections. It would be possible to use VDSL2 digital subscriber lines and implement MIMO concept into the existing metallic networks for this purpose, but before that it will be necessary to solve several problems first. The transmission capacity of present VDSL2 digital lines is limited mainly by crosstalk occurring in metallic cables. This paper describes a new method for modeling of transmission functions and crosstalk in multi-pair and multi-quad metallic cables including its mathematical implementation, and it also gives an example of results obtained so far. The presented model is based on statistical evaluations of measured values, generation of pseudo-random components of frequency response and subsequent filtration process.

关键词： Multi-carrier modulation multiple-input multiple-output vectored DMT modulation crosstalk modeling

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SMSP Mainlobe Jamming Suppression with FDA-MIMO Radar Based on FastICA Algorithm

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SENSORS 2023年第12期23卷 5619-5619页

作者： Wan, Pengfei Liao, Guisheng Xu, Jingwei Fu, Xiaolong Xidian Univ Natl Key Lab Radar Signal Proc Xian 710071 Peoples R China Air Force Engn Univ Air & Missile Def Coll Xian 710051 Peoples R China

In the electronic warfare environment, the performance of ground-based radar target search is seriously degraded due to the existence of smeared spectrum (SMSP) jamming. SMSP jamming is generated by the self-defense jammer on the platform, playing an important role in electronic warfare, making traditional radars based on linear frequency modulation (LFM) waveforms face great challenges in searching for targets. To solve this problem, an SMSP mainlobe jamming suppression method based on a frequency diverse array (FDA) multiple-input multiple-output (MIMO) radar is proposed. The proposed method first uses the maximum entropy algorithm to estimate the target angle and eliminate the interference signals from the sidelobe. Then, the range-angle dependence of the FDA-MIMO radar signal is utilized, and the blind source separation (BSS) algorithm is used to separate the mainlobe interference signal and the target signal, avoiding the impact of mainlobe interference on target search. The simulation verifies that the target echo signal can be effectively separated, the similarity coefficient can reach more than 90% and the detection probability of the radar is significantly enhanced at a low signal-to-noise ratio.

关键词： smeared spectrum jamming frequency diverse array multiple-input multiple-output maximum entropy method blind source separation

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Sixty Years of Coherent Versus Non-Coherent Tradeoffs and the Road From 5G to Wireless Futures

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IEEE ACCESS 2019年 7卷 178246-178299页

作者： Xu, Chao Ishikawa, Naoki Rajashekar, Rakshith Sugiura, Shinya Maunder, Robert G. Wang, Zhaocheng Yang, Lie-Liang Hanzo, Lajos Univ Southampton Sch Elect & Comp Sci Southampton SO17 1BJ Hants England Hiroshima City Univ Grad Sch Informat Sci Hiroshima 7313194 Japan Univ Tokyo Inst Ind Sci Tokyo 1538505 Japan Tsinghua Univ Dept Elect Engn Beijing 100084 Peoples R China

Sixty years of coherent versus non-coherent tradeoff as well as the twenty years of coherent versus non-coherent tradeoff in multiple-input multiple-output (MIMO) systems are surveyed. Furthermore, the advantages of adaptivity are discussed. More explicitly, in order to support the diverse communication requirements of different applications in a unified platform, the 5G New Radio (NR) offers unprecendented adaptivity, abeit at the cost of a substantial amount of signalling overhead that consumes both power and the valuable spectral resources. Striking a beneficial coherent versus non-coherent tradeoff is capable of reducing the pilot overheads of channel estimation, whilst relying on low-complexity detectors, especially in high-mobility scenarios. Furthermore, since energy-efficiency is of salient importance both in the operational and future networks, following the powerful Index Modulation (IM) pholosophy, we conceive a holistic adaptive pholosophy striking the most appropriate coherent/non-coherent, single-/multiple-antenna and diversity/multiplexing tradeoffs, where the number of RF chains, the Peak-to-Average Power Ratio (PAPR) of signal transmission and the maximum amount of interference tolerated by signal detection are all taken into account. We demonstrate that this intelligent tripple-fold adaptivity offers significant benefits in next-generation applications of mmWave and Terahertz solutions, in space-air-ground integrated networks, in full-duplex techniques and in other sophisticated channel coding assisted system designs, where powerful machine learning algorithms are expected to make autonomous decisions concerning the best mode of operation with minimal human intervention.

关键词： Coherent channel estimation non-coherent differential encoding sphere decoding decision-feedback multiple-input multiple-output differential space-time modulation energy-efficiency index modulation peak-to-average power ratio 5G New Radio millimeter wave physical layer link budget 6G Terahertz space-air-ground full-duplex channel coding machine learning artificial intelligence

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Multi-output time series forecasting with randomized multivariate Fuzzy Cognitive Maps

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CHAOS SOLITONS & FRACTALS 2023年 176卷

作者： Orang, Omid de Lima e Silva, Petronio Candido Guimaraes, Frederico Gadelha Univ Fed Minas Gerais Machine Intelligence & Data Sci MINDS Lab Belo Horizonte MG Brazil Fed Inst Educ Sci & Technol Northern Minas Gerais Januaria Campus Belo Horizonte MG Brazil Univ Fed Minas Gerais UFMG Dept Comp Sci Belo Horizonte MG Brazil Univ Fed Minas Gerais Dept Comp Sci Av Antonio Carlos 6627 BR-31270901 Belo Horizonte MG Brazil

Fuzzy Cognitive Maps (FCMs) have become a relevant technique for modeling and forecasting time series due to their advantages in dealing with uncertainty and simulating the dynamics of complex systems. Although numerous univariate and multivariate FCM-based forecasting models have been presented in the literature, one of the still open questions is how to enable FCMs to forecast multivariate time series for multiple-input, multiple-output (MIMO) systems with an efficient learning mechanism. from a computational point of view. This paper suggests a randomized MIMO FCM-based forecasting approach called MO-RHFCM to predict low -dimensional multivariate time series. More specifically, MO-RHFCM is a hybrid model merging the concepts of multivariate fuzzy time series, high order FCM (HFCM), and Echo State Networks (ESN). The structure of MO-RHFCM consists of three layers: input layer, reservoir (internal) layer, and output layer. Only the output layer is trainable using the Least Squares minimization algorithm;hence training the proposed MO-RHFCM method is fast and simple. The weights inside each sub-reservoir are selected randomly and remain fixed during the training process. The obtained results indicate the efficacy and validity of the proposed MO-RHFCM technique compared with some machine learning and deep learning baseline models.

关键词： Fuzzy Cognitive Maps multiple-input multiple-output Multivariate fuzzy time series Echo state network Least squares

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Two-Dimensional Ultrasonic Air Temperature Tomography Based on Phase Shift Processing of Multifrequency Measurements

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IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT 2024年 73卷

作者： Sukhanov, Dmitry Khalil, Amoon Tomsk State Univ Fac Radiophys Tomsk 634050 Russia Higher Inst Appl Sci & Technol Damascus 31983 Syria

An iterative method of transmission tomography of air temperature heterogeneities based on ultrasonic sensing is proposed. The direct dependence of the speed of sound in air on temperature is considered. Air flow and related nonstationary effects are not considered. A change in the speed of sound affects the change in the phase shift of ultrasonic waves passing through the area under study. The reconstruction of the spatial distribution of heterogeneities is carried out by tomographic processing of phase differences of waves passing in forward and reverse directions. The phase differences between forward and reverse propagation waves in an a priori specified medium are considered. In the first iteration, a homogeneous environment is considered as an a priori given environment, and in the second iteration, the reconstructed heterogeneous environment obtained in the first iteration is considered. The results of numerical modeling and the results of experimental studies at frequencies from 38 to 43 kHz are presented. The possibility of reconstructing the distribution of temperature of air is shown.

关键词： Tomography Image reconstruction Receivers Acoustics Temperature measurement Temperature distribution Media Air temperature heterogeneities inverse problems multiple-input multiple-output transmission tomography ultrasonic imaging

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A Comparative Analysis of Deterministic Detection and Estimation Techniques for MIMO SFCW Radars

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IEEE ACCESS 2019年 7卷 129848-129861页

作者： Sirignano, Emilio Davoli, Alessandro Vitetta, Giorgio M. Viappiani, Federico Univ Modena & Reggio Emilia Dept Engn Enzo Ferrari I-41125 Modena Italy

In this paper, the problem of the joint estimation of the range and azimuth of multiple targets in a multiple-input multiple-output stepped-frequency continuous wave radar system is investigated. Three deterministic algorithms solving it through an iterative beam cancellation procedure are described;moreover, an iterative technique, based on the expectation-maximization algorithm, is developed with the aim of reflning their estimates. The accuracy achieved by all the considered algorithms is assessed on the basis of the raw data acquired from a low power wideband radar device. Our results evidence that these algorithms achieve similar accuracies, but at the price of different computational efforts.

关键词： Beamforming direction of arrival multiple-input multiple-output radar signal processing stepped-frequency continuous-wave

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Wideband low cost FR4 epoxy based antenna with H-shaped slot for V-band applications

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INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING 2021年第2期31卷 e22348-e22348页

作者： Okan, Tayfun Akcam, Nursel Univ Turkish Aeronaut Assoc Dept Elect & Elect Engn Bahcekapi Quarter Okul St 11 TR-06790 Ankara Turkey Gazi Univ Dept Elect & Elect Engn Ankara Turkey

This article proposes a substrate integrated waveguide (SIW) antenna fed by microstrip transmission to operate in V-band and fifth generation (5G) (60/70 GHz band) applications. The proposed millimeter wave (mm-wave) antenna has an impedance bandwidth of 25.68 GHz (fractional bandwidth of 41%) between 49.77 and 75.45 GHz frequency and has a maximum realized gain of 3.75 dBi. Compared with other studies, the reported antenna has a size reduction of up to 73% with its 8 x 9.7 mm(2)(1.33 lambda x1.61 lambda) dimension. The designed SIW patch is also fed by grounded coplanar waveguide transmission and its results are compared with the one fed by microstrip transmission line. Another important feature of the proposed antenna is that it has a low production cost, since it is printed on a cheap FR4 substrate material. Therefore, the proposed antenna has the potential to meet all the necessary requirements to be used for V-band portable devices and applications. A 2 x 2 multiple-input multiple-output antenna based on the proposed antenna structure is also analyzed with respect to isolation, diversity gain and envelope correlation coefficient and acceptable results are obtained.

关键词： cavity backed antenna microstrip millimeter wave multiple-input multiple-output substrate integrated waveguide

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Secure beamforming design in MIMO NOMA networks for Internet of Things with perfect and imperfect CSI

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COMPUTER NETWORKS 2021年 187卷 107839-107839页

作者： Deng, Yanlin Li, Quanzhong Zhang, Qi Yang, Liang Qin, Jiayin Sun Yat Sen Univ Sch Elect & Informat Technol Guangzhou 510006 Peoples R China Sun Yat Sen Univ Sch Comp Sci & Engn Guangzhou 510006 Peoples R China Hunan Univ Coll Comp Sci & Elect Engn Changsha 410082 Peoples R China Sun Yat Sen Univ Xinhua Coll Guangzhou 510520 Peoples R China

In this paper, we investigate the secure beamforming design in multiple-input multiple-output (MIMO) nonorthogonal multiple access (NOMA) en-abled Internet of Things (IoT) networks, where a controller transmits confidential messages to multiple actuators and a cooperative controller acts as a jammer to prevent a potential eavesdropper from wiretapping the information. Our goal is to maximize achievable secrecy sum rate subject to the successful successive interference cancellation constraint and transmit power constraints of the controller and jammer. When channel state information (CSI) is perfect, we design the secure beamforming by developing an iterative optimization algorithm based on minimum mean square error (MMSE) method. When perfect CSI is not available, we model the channel errors as deterministically-bounded, and propose a robust secure beamforming design algorithm based on weighted MMSE and cutting-set method. The effectiveness of the proposed algorithms is verified by the simulation results.

关键词： Internet of Things Physical layer security multiple-input multiple-output Nonorthogonal multiple access Secure beamforming

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