Channel capacity analysis of non-line-of-sight ultraviolet communication in noncoplanar geometry based on traversing tiny unit method by Peng SONG, Caixia SU, Taifei ZHAO, Jinni CHEN, Lei ZHU, Xiaodan ZHANG

“…Channel capacity reflects the ability of the system to transmit information without errors.The path loss and impulse response of the system were calculated based on traversing tiny unit method,and then the frequency response of the system was obtained by the discrete Fourier transform of the impulse response sampling sequence,and the 3 dB bandwidth of the system was calculated.Considering the shot noise caused by signal light,the signal-to-noise ratio of the system was obtained according to the quantum limit method,and then the relationship between the channel capacity and the geometric parameters of transmitter and receiver in non-line-of-sight noncoplanar ultraviolet communication system were simulated and analyzed by Shannon formula.The results show that the channel capacity decreases with the increase of the off axis angle and the communication distance.When the elevation angles of transmitter and receiver are less than 40°,the channel capacity decreases rapidly with the increase of the elevation angles of transmitter and receiver,and the transmitter elevation angle has a great influence on the channel capacity.The system channel capacity is almost constant with the increase of divergence angle,and the larger the receiver field of view angle,the greater the system channel capacity.…”
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An Analysis Method for Time-, Frequency-, and Energy-Domain Characteristics of Downhole Microseismic Signals and Its Application by Xiao-xu Gao, Xiang-xu Pan, Guang-an Zhu

“…Based on SOS microseismic (MS) monitoring system of a certain mine, time-, frequency-, and energy-domain characteristics of MS signals are analyzed by comprehensively applying one-dimensional discrete Fourier transform (DFT) and one-dimensional discrete wavelet transform (DWT). …”
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Robotic Vision with the Conformal Camera: Modeling Perisaccadic Perception by Jacek Turski

“…Second, the shift of RFs in retinotopic (logarithmic) coordinates is modeled by the shift property of discrete Fourier transform. The perisaccadic mislocalization observed by human subjects in laboratory experiments is the consequence of the fact that RFs' shifts are in logarithmic coordinates.…”
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Theory of Periodic Sequence: A Generalized Formalism of Maxwell’s Equations in Discrete Transform Domain by Ben You, Ke Wu

“…In this article, we propose the theory of periodic sequence (TPS), marking the first effort to mathematically formalize Maxwell’s equations in the discrete transform domain (corresponding to time domain) and to legitimize the application of the discrete Fourier transform to the temporal aspect of Maxwell’s equation. …”
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Eddy Heat Conduction and Nonlinear Stability of a Darcy Lapwood System Analysed by the Finite Spectral Method by Jónas Elíasson

“…They are called the flak amplitudes. A discrete Fourier transform is used for numerical simulations and here frequency combinations appear that the traditional cut-off infinite transforms do not have. …”
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New Channel Estimation Algorithm for Non-Sample-Spaced Channels in Fast Time-Varying OFDM System by 刘顺兰, 汪佳丽

“…The algorithm combined complex exponential basis expansion model and the feedback of DFT（discrete fourier transform）, which was built according to the fraction taps channel approximation.The channel parameters were firstly estimated with the complex exponential basis expansion model based on the fraction taps channel approximation.Then the ICI in fast time-varying OFDM system could be calculated according to the estimated channel parameters. …”
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Low complexity algorithm for PAPR reduction in GFDM system by Jianhui CAI, Guangqiu LI, Jingjie SHEN

“…In order to reduce the peak-to-average power ratio (PAPR) and the implementation complexity of generalized frequency division multiplexing (GFDM) system, the TSLM algorithm based on T-transform and selective mapping (SLM) was proposed.The design idea of the TSLM algorithm was to use the SLM algorithm to increase the number of GFDM time-domain alternative signals to reduce the PAPR, and to use the T-transform to realize the joint operation of the Walsh-Hadamard transform and the inverse discrete Fourier transform to reduce the complexity of the system.To further reduce the PAPR of the GFDM system, the TCSLM algorithm combining the TSLM algorithm and the conversion vector (CV) was proposed, and the CV vector was used to increase the number of GFDM time-domain alternative signals.The results show that when the number of subcarriers is 64, the number of sub symbols is 3 and the number of phase sequences is 2, compared with the SLM algorithm, the implementation complexity of the TSLM and TCSLM algorithm decreases by about 21.9% and 60.9%, respectively.When the complementary cumulative distribution function (CCDF) is 10^-3, the PAPR of the TSLM and TCSLM algorithm decreases by about 0.6 dB and 1 dB, respectively.The error performance of the TSLM and the TCSLM algorithm is improved by about 2 dB when the bit error rate is 10^-3.…”
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60GHz Reverse Modulation Fiber-Wireless System with Two Jointed DSP Algorithms by Long Chen, Ziwei He, Lv Zhao, Bin Zhong

“…In order to improve transmission of this system, the discrete Fourier transform spread (DFT-Spread) technology and the averaging of the channel frequency response (H-averaging) technology are applied. …”
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Bias Errors due to Leakage Effects When Estimating Frequency Response Functions by Andreas Josefsson, Kjell Ahlin, Göran Broman

“…With Welch's method, the discrete Fourier transform is used and the data is segmented into smaller blocks so that averaging can be performed when estimating the spectrum. …”
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Combined DFT and Fuzzy Based Faulty Phase Selection and Classification in a Series Compensated Transmission Line by Praveen Kumar Mishra, Anamika Yadav

“…In order to mitigate this problem, a combined discrete Fourier transform and fuzzy (CDFTF) based algorithm has been proposed in this paper. …”
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Investigation of Range Profiles from a Simplified Ship on Rough Sea Surface and Its Multipath Imaging Mechanisms by Siyuan He, Fan Zhang, Weidong Hu, Lei Zhuang, Xingbin Ye, Guoqiang Zhu

“…The range profiles of a two-dimension (2 D) perfect electric conductor (PEC) ship on a wind-driven rough sea surface are derived by performing an inverse discrete Fourier transform (IDFT) on the wide band backscattered field. …”
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Sensing Fractional Power Spectrum of Nonstationary Signals with Coprime Filter Banks by Xiaomin Li, Huali Wang, Wanghan Lv, Haichao Luo

“…The coprime discrete Fourier transform (DFT) filter banks provide an effective scheme of spectral sensing for wide-sense stationary (WSS) signals in case that the sampling rate is far lower than the Nyquist sampling rate. …”
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Rapid Driving Style Recognition in Car-Following Using Machine Learning and Vehicle Trajectory Data by Qingwen Xue, Ke Wang, Jian John Lu, Yujie Liu

“…Then, the driving style recognition model’s inputs are extracted from vehicle trajectory features, including acceleration, relative speed, and relative distance, using Discrete Fourier Transform (DFT), Discrete Wavelet Transform (DWT), and statistical method to facilitate the driving style recognition. …”
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RESEARCH ON FATIGUE DAMAGE OF ELECTRICAL CONNECTOR JACK SPRINGS UNDER TRIAXIAL RANDOM VIBRATION CONDITIONS by WEN BaoHua, XU FengLin, ZHAO Hua, CAI YangTao, QI JiaLei, PAN Jun

“…Accordingly, the inverse non-uniform discrete Fourier transform was applied to stress acceleration test of electrical connector was carried out in a tri-axial random vibration environment. …”
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A Next-Generation Codebook Evolution Strategy for Massive Arrays Using Deep Neurals Networks by Minwoo Choi, Wonjin Sung

“…The discrete Fourier transform (DFT)-based codebook is currently among the mostly commonly adopted codebooks for beamforming using arrays of different shapes and sizes, including the large-scale two-dimensional uniform planar array (UPA). …”
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Real-Time Stitching Algorithm of Vehicle Side View Image Based on Multi-Region Fast Phase Correlation by Mubin Xu, Xiaoyong Liu, Chuanhai Wan

“…Subsequently, multi-region phase correlation and registration check based on normalized cross-correlation are used to improve the accuracy of registration, and a local inverse discrete Fourier transform method is proposed to improve the computational efficiency. …”
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Robust dual-tone multi-frequency tone detection using k-nearest neighbour classifier for a noisy environment by Arunit Maity, P. Prakasam, Sarthak Bhargava

“…The features required for training the proposed KNN classifier are extracted using Goertzel's algorithm that estimates the absolute discrete Fourier transform (DFT) coefficient values for the fundamental DTMF frequencies with or without considering their second harmonic frequencies. …”
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Sparse Orthogonal Circulant Transform Multiplexing for Coherent Optical Fiber Communication by Yukui Yu, Wei Wang, Xing Ouyang, Zhenpeng Wang, Jian Zhao

“…We compared the proposed scheme with conventional orthogonal frequency division multiplexing (OFDM), orthogonal chirp division multiplexing (OCDM), and discrete-Fourier-transform spreading OFDM (DFT-S-OFDM) in a coherent optical communication system. …”
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Exploring Aggregated wav2vec 2.0 Features and Dual-Stream TDNN for Efficient Spoken Dialect Identification by Ananya Angra, H. Muralikrishna, Dileep Aroor Dinesh, Veena Thenkanidiyoor

“…The GAF layer employs a set of learnable transform-domain filters between a 1D discrete Fourier transform and its inverse transform to capture global context along with dynamic filtering and sparse regularization. …”
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Processing of retransmitted GPS signals in the problem of measuring the total electron content in the ionosphere by Y. A. Kapliarchuk, S. V. Kozlov, I. E. Savinykh, A. S. Shapkin

“…Coherent accumulation, taking into account a random uncontrolled shift in the frequency of the retransmitted signal, is implemented by discrete Fourier transform of the vectors formed for each resolution element in the delay time from inter-period readings of the results of intra-period processing, taking into account the range migration during the mutual movement of the NS, SR and RP.Results. …”
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