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High Anti-Interception Orbital Angular Momentum Spread Spectrum Communications Systems
ICC 2021 - IEEE International Conference on Communications, 2021With the same transmission rate and Bit Error Rate (BER) as the traditional Direct Sequence Spread Spectrum (DSSS) system, the stronger anti-interception performance can be obtained by Orbital Angular Momentum (OAM). In other words, the contradiction between the transmission rate and the security can be solved by the double-channel OAM Spread Spectrum (
Wanyu Tian, Xuefeng Jiang, Chao Zhang
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Cluster Angular Spreads in a MIMO Indoor Propagation Environment
2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications, 2006An important parameter of MIMO channel models is the cluster root-mean-square (rms) directional spread. In this paper we determine this parameter in the azimuth-of-arrival/azimuth-of-departure (AoA/AoD) domain based on comprehensive indoor MIMO measurements at 5.2 GHz in a cluttered office environment.
N. Czink +3 more
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Impact of Angular Spread on Moderately Large MIMO Systems
2018 IEEE International Conference on Communications Workshops (ICC Workshops), 2018Pilot contamination is 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 +2 more
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MIMO channel sounding taking into account small angular spread
The 13th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 2003The use of multiple receive antennas as well as multiple transmit antennas has attracted worldwide attention to extend the performance of existing mobile communication systems. Therefore, it is of great importance to know the features of the real propagation channel.
T.R. Kurpjuhn, W. Utschick
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The Angular Spread of Hard Cosmic-Ray Showers
Physical Review, 1938In order to account for the experimental results of Schmeiser and Bothe, the "dynaton" theory has to be modified by the introduction of a "form-factor" which reduces the probability of showers with large angular divergence. A particular invariant "cutting off" rule is discussed.
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Decoupled estimation of DOA and angular spread for a spatially distributed source
IEEE Transactions on Signal Processing, 2000Summary: In mobile communications, local scattering in the vicinity of the mobile results in angular spreading as seen from a base station antenna array. In this paper, we consider the problem of estimating the parameters [direction of arrival (DOA) and angular spread] of a spatially distributed source, using a uniform linear array.
Besson, Olivier, Stoica, Petre
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Low Complexity Estimation of Angular Spread with an Antenna Array
IFAC Proceedings Volumes, 1997Abstract When sensor array processing is applied in for example mobile communication applications, more parameters than the direction of arrival are necessary to properly describe the propagation channel. Here, a new low complexity algorithm is proposed for estimation of the angular spread caused by local scattering around a mobile source.
Mats Bengtsson, Björn Ottersten
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Signal waveform estimation from array data in angular spread environment
Conference Record of The Thirtieth Asilomar Conference on Signals, Systems and Computers, 2002We analyze different direction based signal copy algorithms for a model of angular spread caused by local scattering around each signal source. Optimal algorithms, in terms of signal to interference and noise ratio, are derived for both rapidly and slowly time varying angular spread and a low complexity an-hoc algorithm is suggested.
M. Bengtsson, B. Ottersten
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1969
The next step is to make some allowance for the fact that the reflections from the earth and from the ionosphere are not specular. The case which we are now considering is a little different from that considered in chapter 7 where the rough ionospheric and earth reflections gave rise to the day-to-day wandering of the rays.
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The next step is to make some allowance for the fact that the reflections from the earth and from the ionosphere are not specular. The case which we are now considering is a little different from that considered in chapter 7 where the rough ionospheric and earth reflections gave rise to the day-to-day wandering of the rays.
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A new MIMO spatial correlation approximation of large angular spread
2007 IEEE Antennas and Propagation Society International Symposium, 2007This paper proposes a new approximate correlation calculation where the angle-of-arrival (AoA) distribution is the uniform distribution. Moreover, this study takes mutual coupling effect into consideration and investigates how mutual coupling affects the correlation.
null Po-Chuan Hsieh +1 more
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