Results 251 to 260 of about 847,355 (293)

Delay Spread Prediction for Wideband Mobile Propagation

IEEE Vehicular Technology Conference, 2006
In designing high-speed digital mobile communication systems, we must predict the multi-path propagation characteristics more accurately. Delay spread is an effective indicator that makes it easy to evaluate multi-path propagation. In this paper, we propose a novel delay profile model that can predict the delay spread accurately due to its inclusion of
Yoshichika Ohta, Teruya Fujii
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Measurement of UHF delay spread in building

ICMMT'98. 1998 International Conference on Microwave and Millimeter Wave Technology. Proceedings (Cat. No.98EX106), 2002
This paper brief reports the experimental study on the indoor radio propagation with emphasis on the delay spread, for it may be the major constrain for high bit-rate transmission. The measurements are done in the building of the Department of Electronic Engineering of Tsinghua University by using sliding correlated spread spectrum approach, the ...
null Gong Ke, null Qian Jianzhong, null Zhao Yuping   +2 more
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Delay estimation of code-spread CDMA systems

VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026), 2002
Delay estimation of a code-spread code division multiple access (CS-CDMA) system using low-rate maximum free distance (MFD) convolutional codes for bandwidth expansion is studied. Using the repetitive structure of the low-rate MFD codes, the codewords are first permuted using a criterion based on the Cramer-Rao bound that results in good delay ...
F. Malmsten, T. Ottosson, E.G. Strom
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Delay spread estimation for wireless communication systems

Proceedings of the Eighth IEEE Symposium on Computers and Communications. ISCC 2003, 2004
In this paper, average frequency correlation and root-mean-squared (rms) delay spread estimation for wireless communication systems are described. A practical algorithm for averaged channel frequency correlation estimation, which can be used for measuring frequency selectivity, is given. Average rms delay spread of the channel is obtained directly from
H. Arslan, T. Yucek
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Rumour Spreading with a Delaying Scheme

2017
Randomised rumour spreading scheme is an extremely simple and powerful model to represent a propagation of information within members of a network. We studied a particular variation of the rumour spreading scheme where the informed individuals are periodically absent from the spreading activity with a certain rate called the switching rate.
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Delay included dynamic virus spreading process simulating

2013 25th Chinese Control and Decision Conference (CCDC), 2013
In classical virus spread model, the virus spreading process is described by infected probability, this process ignored some spreading details and the duration of contact. For this reason, we proposed a delay included dynamic virus spreading model and simulated the viruses' spreading process by cellular automata method. The unexpected result shows that
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Path loss and delay spread in UWB channels

2009 IEEE Antennas and Propagation Society International Symposium, 2009
This work presents an analysis of a UWB measurement campaign. Results focus on the wideband path loss, concluding that frequency dependence and distance dependence can be studied separately. In the case of the frequency dependence, similar results to the theoretical prediction (free space propagation) are found. On the other hand, the slope of the path
J.-M. Molina-Garcia-Pardo, Concepcion Garcia-Pardo, J.-V. Rodriguez, L. Juan-Llacer   +3 more
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Experimental analysis of the joint statistical properties of azimuth spread, delay spread, and shadow fading

IEEE Journal on Selected Areas in Communications, 2002
Empirical results characterizing the joint statistical properties of the local azimuth spread (AS), the local delay spread (DS), and the shadow (slow) fading component are presented. Measurement data from typical urban, bad urban, and suburban (SU) environments have been analyzed.
Algans, Albert, Pedersen, Klaus Ingemann, Mogensen, Preben Elgaard   +2 more
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Delay spread in microcells analysed with waveguide theory

Vehicular Technology Conference. IEEE 55th Vehicular Technology Conference. VTC Spring 2002 (Cat. No.02CH37367), 2003
Waveguide theory is suggested for the analysis of UHF radiation in urban microcellular environments, where both the transmitter and the receiver are below rooftop level. The delay profile is calculated from the steady state power distribution among the modes of the waveguide. The delay profile is very asymmetrical because most of the power is contained
D. Porrat, D.C. Cox
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Delay spread and time delay jitter for the UHF factory multipath channel

38th IEEE Vehicular Technology Conference, 2003
The results of wideband delay spread and time-delay jitter measurements collected from five factory buildings are presented. Carrier frequency was 1282 MHz. The data show that excess mean delay, RMS delay spread, and time-delay jitter values in single-storey factory buildings are similar to values observed in and around multistorey office buildings ...
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