Results 1 to 10 of about 264,735 (274)
Localization of Spatially Distributed Near-Field Sources with Unknown Angular Spread Shape [PDF]
Signal Processing, 2015 International audienceIn this paper, we propose to localize and characterize coherently distributed (CD) sources in near-field. Indeed, it appears that in some applications, the more the sources are close to the array of sensors, the more they can seem ...
Abou Chaaya, Jad +2 more
core +7 more sources
Effects of angular spread in nonlinear Compton scattering [PDF]
Physical Review D, 2023 We investigated the effects of the momentum spread of photon around incoming electrons during nonlinear Compton scattering of an elliptically polarized laser off an ultrarelativistic electron beam. It has been assumed to be a good approximation to neglect the angular spread in the strong-field QED codes considering its smallness in relativistic regime.
Dai, Ya-Nan +4 more
+6 more sources
A comparative study of the beam-width spreading and angular spread in atmospheric turbulence
Acta Physica Sinica, 2009 Taking the HermitecoshGaussian（HChG） beam as a typical example, the beamwidth spreading and angular spread of HChG beams propagating through atmospheric turbulence are throughly studied. The relative beamwidth and relative angular spread instead of the beamwidth and angular spread have been used to study the sensitivity of a beam to the effect ...
null Yang Ai-Lin +2 more
openaire +2 more sources
Exploiting angular spread in channel estimation of millimeter wave MIMO system [PDF]
IET Communications, 2022 Millimeter wave (mmWave) frequency spectrum can mitigate severe spectrum shortage caused by the explosive growth of mobile data demand. To overcome the high propagation loss of mmWave signals, massive multi‐input multi‐output (MIMO) and hybrid ...
You You, Li Zhang
doaj +2 more sources
Angular spreading measurements using MeV ion microscopes
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2013 Abstract The sharpness of MeV ion microscope images is governed by small-angle scattering and associated lateral spreading of the ion beam in the sample. We have investigated measurement of the half-angle of the angular spreading distribution by characterising the image blurring in direct-Scanning Transmission Ion Microscopy (direct-STIM).
Ren, Minqin +6 more
openaire +3 more sources
Tracking Sparse mmWave Channel: Performance Analysis Under Intra-Cluster Angular Spread [PDF]
2018 IEEE 19th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), 2018 Millimeter-wave (mmWave) systems require a large number of antennas at both base station and user equipment for a desirable link budget. Due to time varying channel under user mobility, up-to-date channel state information (CSI) is critical to obtain the required beamforming gain..
Yan, Han +2 more
+7 more sources
Impact of Angular Spread in Moderately Large MIMO Systems Under Pilot Contamination [PDF]
IEEE Transactions on Vehicular Technology, 2018 Pilot contamination is known to be one of the main bottlenecks for massive multi-input multi-output (MIMO) networks. For moderately large antenna arrays (of importance to recent/emerging deployments) and correlated MIMO, pilot contamination may not be the dominant limiting factor in certain scenarios.
Nadisanka Rupasinghe +3 more
+6 more sources
Matching in the Air: Optimal Analog Beamforming under Angular Spread [PDF]
, 2019 Gbps wireless transmission over long distance at high frequency bands has great potential for 5G and beyond, as long as high beamforming gain could be delivered at affordable cost to combat the severe path loss. With limited number of RF chains, the effective beamwidth of a high gain antenna will be "widened" by channel angular spread, resulting in ...
Du, Jinfeng +3 more
openaire +3 more sources
A new algorithm for point spread function subtraction in high-contrast imaging: a demonstration with angular differential imaging [PDF]
, 2007 Direct imaging of exoplanets is limited by bright quasi-static speckles in the point spread function (PSF) of the central star. This limitation can be reduced by subtraction of reference PSF images.
Artigau, Etienne +4 more
core +2 more sources
Angular and lateral spreading of ion beams in biomedical nuclear microscopy
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2009 Abstract Nuclear scattering from target atoms gives rise to a spatial broadening of energetic ion beams penetrating matter. The spatial broadening of the ion beam presents an ultimate limit to the resolving power that can be achieved in nuclear microscopy methods.
Whitlow, H.J. +4 more
openaire +3 more sources