Results 81 to 90 of about 3,627 (192)
The imaging algorithm in the optimal range FrFT domain based on Doppler parameters [PDF]
AIP AdvancesIn view of the error impact of Doppler parameters estimation on SAR imaging performance, this paper constructs the energy focusing axis based on the optimal rotation angle in the optimal range FrFT (fractional Fourier transform) domain.
Z. L. Wang, Y. Xu, J. Y. Liu, G. L. Gao
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Interferometry-based modal analysis with finite aperture effects
, 2018 We analyze the effects of aperture finiteness on interferograms recorded to unveil the modal content of optical beams in arbitrary basis using generalized interferometry. We develop a scheme for modal reconstruction from interferometric measurements that
Abouraddy, Ayman F. +2 more
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Intelligent OFDM telecommunication system. Part 4. Anti-eavesdropping and anti-jamming properties of the system, based on many-parameter and fractional Fourier transforms [PDF]
, 2019 In this paper, we aim to investigate the superiority and practicability of many-parameter wavelet and Golay transforms (MPWT and MPGT) from the physical layer security (PHY-LS) perspective.
Chasovskikh, V. P. +4 more
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Applied SciencesTo address the challenge of monitoring BeiDou RDSS signals under low signal-to-noise ratio (SNR) and high-dynamic conditions, this paper introduces a hierarchical joint processing algorithm combining PMF-FFT and PMF-FRFT.
Huaiyi Guan +6 more
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Anti‐eavesdropping FrFT‐OFDM system exploiting multipath channel characteristics
IET Communications, 2017 This study exploits wireless channel response and fractional Fourier transform (FrFT) to achieve anti‐eavesdropping downlink transmission over a multipath channel. The proposed system works in time‐division duplexing mode, and only the transmitter knows the main channel response through uplink services.
Teng Wang, Hao Huan, Ran Tao, Yue Wang
openaire +1 more source
Conformal geometry of surfaces in the Lagrangian--Grassmannian and second order PDE
, 2010 Of all real Lagrangian--Grassmannians $LG(n,2n)$, only $LG(2,4)$ admits a distinguished (Lorentzian) conformal structure and hence is identified with the indefinite M\"obius space $S^{1,2}$.
The, Dennis
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Fractal and FractionalTo address the limitations of traditional tumor diagnostic methods in image feature extraction and model generalization, this study innovatively proposes a synergistic diagnostic model that integrates fractional Fourier transform (FrFT) and error back ...
Xuanyu Liu +3 more
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Electron tomography at 2.4 {\AA} resolution
, 2012 Transmission electron microscopy (TEM) is a powerful imaging tool that has found broad application in materials science, nanoscience and biology(1-3). With the introduction of aberration-corrected electron lenses, both the spatial resolution and image ...
Chen, Chien-Chun +8 more
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Acquisition algorithm for BOC signals in high dynamic environment
Tongxin xuebao, 2019 As the synchronization of binary offset carrier (BOC) signals couldn’t be realized in high dynamic environment by traditional acquisition algorithms,an acquisition algorithm based on fractional Fourier transform (FRFT) and discrete polynomial-phase ...
Yi PAN +3 more
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Application of Fractional Fourier Transform to Hologram Formation of a Moving Acoustic Source
Fractal and FractionalThis paper examines how the fractional Fourier transform (FrFT) can be used to form and analyze acoustic holograms produced by a moving, linear, frequency-modulated (LFM) source in a shallow water waveguide.
Sergey Pereselkov +5 more
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