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Spatial Statistics of Spectrum Usage: From Measurements to Spectrum Models
2009 IEEE International Conference on Communications, 2009Several measurement studies have found a large amount of underutilized radio spectrum. More flexible regulation employing dynamic spectrum access (DSA) has been proposed as solution to this problem. The analysis of several aspects of DSA systems, e.g., cooperative sensing, requires good spatial models of spectrum usage.
Wellens M. +3 more
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Spatial distributed dynamic spectrum access
2013 IEEE International Conference on Communications (ICC), 2013The spatial aspect of distributed dynamic spectrum access (DSA) in a wireless ad hoc network is usually overlooked in the literature. By using tools from stochastic geometry, we analytically characterized the spatial distribution of users and subsequent interference in the network.
Ching-Yueh Kao +2 more
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An action spectrum for spatial-frequency adaptation
Vision Research, 1982The mechanism of spatial-frequency adaptation, and channel-bandwidth estimates derived from adaptation, were examined in a series of three experiments. The first two experiments measured adaptation as a function of both the frequency and modulation of the adapt stimulus.
D J, Swift, R A, Smith
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Indoor Positioning Using Spatial Power Spectrum
2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications, 2006A simple technique to estimate the position of a given mobile source inside a building is based on the received signal strength. For this methodology to have a reasonable accuracy, radio visibility of the mobile by at least three access points is required.
K. Sayrafian-Pour, D. Kaspar
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Spatial and Spectrum Feature Extraction
2018In this chapter, we present a study on computational pulse diagnosis based on blood flow velocity signal. First, the blood flow velocity signal is collected using Doppler ultrasound device and preprocessed. Then, by locating the fiducial points, we extract the spatial features of blood flow velocity signal and further present a Hilbert-Huang transform ...
David Zhang, Wangmeng Zuo, Peng Wang
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Spatial focusing inspired 5G spectrum sharing
2017 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2017Next-generation wireless networks are expected to support exponentially increasing number of users and demands of data, which all rely on the essential media: spectrum. Notice that the 5G networks are featured either by wide bandwidth like mmWave systems, or by large-scale antennas like massive MIMO.
Chunxiao Jiang +4 more
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A spatial power spectrum analysis of the electroencephalogram
Brain Topography, 1990The method of spatial power-spectrum analysis has been applied to measurements of the distribution of rms alpha-band potential on the scalp. Data was recorded using the 31-Electrode System and spatial power-spectrum estimates (PSEs) were obtained from Mercator projections of the potential interpolated using the triangular method.
R B, Paranjape, Z J, Koles, J, Lind
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Spectrum Sharing for UAV Communications: Spatial Spectrum Sensing and Open Issues
IEEE Vehicular Technology Magazine, 2020Unmanned aerial vehicles (UAVs) are attracting increasing attention for applications such as video streaming, surveillance, and delivery using reliable line-of-sight (LOS) links. Nevertheless, due to the large radio-frequency (RF) transmission footprint from a UAV transmitted to ground nodes, UAV communications may significantly deteriorate the ...
Bodong Shang +4 more
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Beamspace Synthetic Spatial Spectrum DOA Estimator
2008 Fourth International Conference on Natural Computation, 2008In this paper, we develop a new estimator of DOA named Synthetic Spatial spectrum Method (SSM) to beamspace processing. Beamspace transformation maps the full dimension sensor space data onto a lower dimension space. Then the SSM deals with covariance matrix of beamspace data directly.
Wang Qiong, You Hong
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Spontaneous spatial navigation circuitry in schizophrenia spectrum disorders
Psychiatry Research, 2019Spatial memory is core to wayfinding and everyday memory. Interestingly, individuals with schizophrenia using spatial navigation strategies (cognitive mapping) are impaired, whereas those using response-based (e.g., single-landmark) strategies show relatively intact memory performance.
Leanne K, Wilkins +5 more
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