Results 11 to 20 of about 4,714 (163)
Robust direction-of-arrival estimation based on sparse asymptotic minimum variance
The Journal of Engineering, 2019 This study proposes a direction-of-arrival (DOA) estimation algorithm named robust sparse asymptotic minimum variance (RSAMV) to solve the current DOA algorithms' problems, such as the difficulty in weak target estimation, low resolution and the ...
Xiangyu Zhang, Jun Sun, Xingrong Cao
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A hybrid spectrum opportunities extraction scheme for cognitive wireless communication
Telematics and Informatics Reports, 2022 A realistic and credible model capable of forecasting spectrum occupancy patterns of primary users (PU) needs to be developed to improve the functioning of cognitive radio networks (CRNs) in terms of the spectrum decision process.
Frederick Ojiemhende Ehiagwina +3 more
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Null widening method for conformal array based on covariance matrix enhancement
The Journal of Engineering, 2019 Conformal arrays are widely used in various aircrafts since they do not affect the aerodynamic performance of the carriers. When conformal arrays are used to suppress fast-moving interference, it is possible that the weight mismatches the data of ...
Zhanze Wang +3 more
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Annals of Geophysics, 1999 The separation of the field produced by different internal sources can be accomplished by means of the so-called spatial spectrum of the geomagnetic field of internal origin.
X. Q. Gao +3 more
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Differential Effects of Orientation and Spatial-Frequency Spectra on Visual Unpleasantness
Frontiers in Psychology, 2020 Increasing psychophysical evidence suggests that specific image features – or statistics – can appear unpleasant or induce visual discomfort in humans. Such unpleasantness tends to be particularly profound if the image’s amplitude spectrum deviates from ...
Narumi Ogawa, Isamu Motoyoshi
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IEEE Access, 2023 The two-dimensional optimization capability of the space-time minimum variance distortionless response (STMVDR) can improve the spatial spectrum estimation performance of the broadband beamformer with limited samples, but its high sensitivity to ...
Yang Wang +3 more
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Spatial spectrum based blind spectrum sensing for multi-antenna cognitive radio system
Tongxin xuebao, 2015 State-of-the-art sensing methods only exploit three dimensions of the spectrum space:frequency，time and space whereas the angle dimension has not been exploited well enough for opportunistic spectrum access.Motivated by this，the authors apply angle of ...
Chang LIU +5 more
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A two level multi-antenna blind spectrum detection about spatial spectrum
Dianxin kexue, 2018 In order to improve the perceptual performance,the array spatial spectrum search technology was applied to the spectrum sensing field.A blind spectrum detection algorithm based on two stage detection of spatial spectral values was proposed.Firstly,the ...
Zhiqiang BAO, Yanrui CUI, Xiao XU
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Revealing the structure of land plant photosystem II: the journey from negative‐stain EM to cryo‐EM
FEBS Letters, EarlyView.Advances in cryo‐EM have revealed the detailed structure of Photosystem II, a key protein complex driving photosynthesis. This review traces the journey from early low‐resolution images to high‐resolution models, highlighting how these discoveries deepen our understanding of light harvesting and energy conversion in plants.
Roman Kouřil
wiley +1 more source
Error Self-calibration Method in Spatial Spectrum Estimation
Leida xuebao, 2014 An important bottleneck in spatial spectrum estimation theory is array errors. A new error self-calibration method is presented on the basis of active error calibration and online self-calibration theories.
Huang Chuan-lu, Chao Kun, Mao Yun-zhi
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