Faster-than-Nyquist signaling: value and challenges of 6G-oriented applications by Xin SU, Sen WANG, Hongwen YANG, Jing JIN, Qixing WANG

“…The faster-than-Nyquist (FTN) signaling technology overlaps multiple streams of data within a symbol period by compressing the transmit symbol time/frequency-domain interval, thus breaking the orthogonality of the Nyquist pulse waveform and achieving the purpose of transmitting more data in a limited bandwidth.A relatively comprehensive explanation of the technical principles of FTN was elaborated, its development status was sorted out, and the related key questions——the relationship between FTN capacity and Shannon capacity, and the intrinsic connection of related technologies were answered.Finally, The possibility of FTN application in 6G was discussed, and its value and challenges in 6G were presented.That is, FTN is a highly spectrally efficient transmission scheme that approximates Shannon's capacity, but excessive receiver complexity may be a key impediment to its use in 6G applications.…”
Get full text

Performance optimization method of GFDM system based on WFRFT spectral precoding by Zhenduo WANG, Zhaohui WANG, Ruoyu ZHANG

“…Generalized frequency division multiplexing (GFDM) system always faces challenges related to out-of-band (OOB) power leakage and a high peak-to-average power ratio (PAPR).Through an in-depth analysis of power spectrum characteristics of spectrally precoded GFDM systems, a universal spectral precoding (SP) framework based on the weighted fractional Fourier transform (WFRFT) was established.A two-dimensional parameter-adjustable WFRFT-SP-GFDM system was introduced.By flexibly configuring the parameters, the WFRFT spectral precoder could be made to approximate the weighted fractional Fourier transform matrix, achieve precise control over OOB power and PAPR.Simulation results indicate that, when compared to conventional GFDM and WFRFT-GFDM waveforms, the WFRFT-SP-GFDM waveform effectively suppresses OOB power leakage, while maintaining favorable PAPR and bit error rate (BER) performance.…”
Get full text

SIMULATION OF OPEN MECHANISMS FOR THE ADDITIVE PROCESS WELD PLASTICS by N. N. Hurski, V. A. Skachek, A. V. Skachek, Y. A. Skudnyakov

“…We present the initial data and the results of simulation of 3D-printer type Scara as a waveform positioning actuator (extruder) in the manufacture of test items by fusing plastic.…”
Get full text

ANALYSIS ON DYNAMIC CHARACTERISTICS OF TOOTH ROOT CRACK OF GEAR DRIVE SYSTEM UNDER VARIABLE LOAD EXCITATION by SHI PeiMing, ZHAO Na, LIANG Kai, HAN DongYing

“…Analysis shows that,under variable load excitation,the vibration wave forms are very similar to the variable load excitation; Cracks caused by the impact phenomenon on the waveform and meshing frequency and its harmonics appear sideband.Sideband spectrum of the meshing frequency is the rotating frequency of the fault gear; Under variable load excitation,the frequency components of the low frequency is related to the variable load excitation.…”
Get full text

Radio signal recognition based on image deep learning by Xin ZHOU, Xiaoxin HE, Changwen ZHENG

“…A technical idea was innovatively proposed that uses image deep learning to solve the problem of radio signal recognition.First,the radio signal was transformed into a two-dimensional picture,and the radio signal recognition problem was transformed into the object detection problem in the field of image recognition.Then,the advanced achievements about image recognition were used to improve the intelligence and ability of radio signal recognition in complex electromagnetic environment.Based on the proposed idea,a novel radio signal recognition algorithm named RadioImageDet was proposed.The experimental results show that the algorithm can effectively identify the waveform types and time/frequency coordinates of radio signals.After training and testing on the self-collected data set with 12 types and 4 740 samples,the accuracy reaches 86.04% and the mAP value reaches 77.72,while the detection time is only 33 ms on the medium configured desktop computer.…”
Get full text

Research on reference signal scheme for high-mobility scenarios in the Terahertz frequency band by LIU Liping, BAO Tong, XIN Yu, HU Liujun

“…Simulation results demonstrate that this scheme provides more precise channel estimation and greater spectral efficiency than DMRS scheme with 5G NR DFT-s-OFDM waveform for high-mobility scenarios in the Terahertz band.…”
Get full text

Fatigue Damage Evolution and Monitoring of Carbon Fiber Reinforced Polymer Bridge Cable by Acoustic Emission Technique by Dongsheng Li, Qian Hu, Jinping Ou

“…Finally, the failure types of AE waveform are extracted and analyzed using wavelet transformation. …”
Get full text

A transmission technology of environmental monitoring for ocean based on over-the-horizon skywave by Guojun LI, Xiaofei XU, Changrong YE, Deping ZHANG, Lu TAN, Yakun XING

“…In view of the serious limitation of local resource supply for remote island and reef and the lack of low cost,high reliability long-distance transmission methods for environmental monitoring,relying on the mobile communication base stations widely distributed on the land,an over-the-horizon(OTH) skywave access network based on wide-area cooperative reception was proposed.The problems of channel fading,link asymmetry and spectrum congestion faced by remote island and reef environments monitoring for an OTH skywave transmission were solved from three aspects:physical layer,network layer and perceptive layer.The simulation results of the lower link transmission waveform and the multi-channel fusion algorithm in the typical skywave channel environment show that the reliable access of low-power transceiver in the remote island and reef within a range of 3 000 km could be guaranteed only through the cooperative reception of three access nodes.There was also some reference to monitoring of national ocean-going ships and border defence traffic pass monitoring.…”
Get full text

Noise Radar Technology as an Interference Prevention Method by Gaspare Galati, Gabriele Pavan

“…The advent of fast digital signal processing and signal generation techniques makes it possible to use waveform diversity to solve this problem that will be exacerbated in the next future. …”
Get full text

改进MOMEDA方法及其在滚动轴承故障特征增强中的应用 by 陈丙炎, 宋冬利, 张卫华, 程尧

“…Aiming at the shortcomings of multipoint optimal minimum entropy deconvolution adjusted（ MOMEDA） method,which cannot automatically identify the fault impulse period and shorten the length of deconvolved signal when enhancing bearing fault features,an improved MOMEDA（ IMOMEDA） method is proposed.The autocorrelation spectrum of square envelope of the vibration signal is used to adaptively identify the fault period,and the estimated impulse period is used to deconvolve the vibration signal to enhance the periodic impulse features.Then the signal waveform extension method is used to extend the deconvolved signal to make its length consistent with the original signal.Finally,the obtained filtered signal is deconvolved for a certain number of times to effectively enhance the periodic features of the original signal.The analysis results of simulated bearing fault signal and railway bearing experiment signals and the comparisons with Kurtogram method show that the improved MOMEDA method can automatically identify the fault impulse period and effectively enhance the fault characteristics of rolling bearing.…”
Get full text

Research of the Gear Fault Diagnosis based on Improved LMD and Manifold Learning by Shen Chao, Yang Jianwei, Yao Dechen, Li Xi

“…Firstly,by using the local mean decomposition（LMD） to decomposed the original vibration signal to obtain the components in different scales,and increases the adaptive matching waveform to alleviate the influence of end effects on decomposition results in the original LMD method. …”
Get full text

Prototype Instrumentation for the Spatial and Temporal Characterisation of Voltage Supply Based on Two-Dimensional Higher-Order Statistics by Juan-José González-de-la-Rosa, Olivia Florencias-Oliveros, José-María Sierra-Fernández, Manuel-Jesús Espinosa-Gavira, Agustín Agüera-Pérez, José-Carlos Palomares-Salas, Victor Pallarés-López, Rafael-Jesús Real-Calvo, Isabel Santiago-Chiquero

“…Waveforms were measured in the wall plugs of a public building. …”
Get full text

A realistic 2D multi-offset, multi-frequency synthetic GPR data set as a benchmark for testing new algorithms by G. Roncoroni, P. Koyan, E. Forte, J. Tronicke, M. Pipan

“…The data set provides a robust framework for validating advanced GPR algorithms and techniques such as pre-stack depth migration, amplitude versus offset analysis and full waveform inversion. Extensive technical validation ensures data reproducibility and affordability. …”
Get full text

Three-Dimensional Target Localization and Cramér-Rao Bound for Two-Dimensional OFDM-MIMO Radar by Xingxing Li, Dangwei Wang, Xiaoyan Ma

“…In this paper, three-dimensional (3D) target localization is considered for two-dimensional MIMO radar with orthogonal frequency division multiplexing linear frequency modulated (OFDM-LFM) waveforms. To realize joint estimation for range and angle in azimuth and elevation, the range-angle-dependent beam pattern with high range resolution is produced by the OFDM-LFM waveform. …”
Get full text

Real-Time Monitoring of High Voltage Switch Based on CAD by Long Di, Yong Xiao, Feng Hu, Yujian Liang, Jianmin Tan, Yimin You

“…Through fault simulation experiment and mechanical stability experiment, the corresponding changes of characteristics of each mechanical component of circuit breaker in signal waveform and corresponding data changes are found. …”
Get full text

Grid-Connection Half-Bridge PV Inverter System for Power Flow Controlling and Active Power Filtering by Chih-Lung Shen, Jye-Chau Su

“…For current controlling, a direct-source-current-shaping (DSCS) algorithm is presented to shape the waveform of line current. Simulation results and practical measurements also demonstrate the feasibility of the proposed half-bridge PV system.…”
Get full text

Novel unified chaotic system with multi-parameter invariable Lyapunov exponent spectrum by Qiuzhen WAN, Zhaoteng ZHOU

“…Based on the traditional Qi chaotic system,a novel unified chaotic system with the complex chaotic characteristics was constructed by adding the control parameters and modifying the nonlinear terms.Firstly,basic dynamical characteristics of chaotic system were analyzed,and phase portrait,time domain waveform diagram,Poincare mapping and power spectrum diagram were numerically simulated.Secondly,system parameters influence on chaotic system was discussed through Lyapunov exponent spectrum,bifurcation diagrams and chaotic signal amplitude.It was found that the unified chaotic system can generate the four new types of two-wing chaotic attractors with the multi-parameter invariable Lyapunov exponent spectrum characteristics.Meanwhile,there exist the functions of the global and local nonlinear amplitude modulation parameters.Thirdly,taking the first chaotic attractor of system as an example by introducing the two new types of nonlinear functions,the expansion of grid multi-wing attractor was realized.Finally,the hardware circuit of novel unified chaotic system was constructed.The four new types of chaotic attractors are observed experimentally,which is consistent with numerical simulation results and verified the feasibility of the proposed system.…”
Get full text

Research on Torsional Fatigue Test Method of Electric Vehicle Differential based on Actual Driving Load by Xihong Zou, Jinxiao Li, Qiuyang Hu, Shuaijie Xi, Lingfeng Fu, Dongmei Yuan

“…After preprocessing the collected axle shaft torque load spectrum and analyzing the characteristics in time-frequency domain， it is determined that the load waveform of torsional fatigue test is sine wave and the load frequency is 0.5 Hz. …”
Get full text

RESEARCH ON DYNAMICS CHARACTERISTICS OF GEAR-BEARING COUPLING IN FAULTY TRANSMISSION SYSTEM by CAO JinXin

“…The results show that the established dynamic model can well describe the dynamic characteristics of the fault-containing gear transmission system. In the time domain waveform diagram,a periodic shock signal is generated due to the presence of a crack fault,and a sideband is generated around the meshing frequency in the spectrogram.…”
Get full text

X-Parameter Measurement of Pulse-Compression Nonlinear Transmission Lines by Ming Li, Rony E. Amaya, Robert G. Harrison, N. Garry Tarr

“…A specially configured Nonlinear Vector Network Analyzer (NVNA) was used to measure the X-parameters in the frequency-domain, and then the measured data was transformed into a nonlinear time-domain waveform. The results show both rise-time and fall-time reduction (double-edge compression) as expected and indicate that this newly developed X-parameter method implemented with an NVNA could correctly predict NLTLs' pulse-compression performance.…”
Get full text