Results 221 to 230 of about 44,019 (240)

Multisensor active broadband sonar in multipath propagation

'Challenges of Our Changing Global Environment'. Conference Proceedings. OCEANS '95 MTS/IEEE, 2002
Although the use of signals with large bandwidth and duration improves resolution in classical active sonar, problems arise in echo detection when the delay, Doppler and direction parameters are close. The maximum likelihood estimator (MLE) applied to active spatio-temporal signal shows that identification of close highlight points can be achieved.
P. Graffouliere, A. Essebbar
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Directional dependence of indoor multipath propagation characteristics

IEEE Antennas and Propagation Society International Symposium 1992 Digest, 1992
The directional characteristics of indoor multipath propagation are derived from measurements of delay profiles. The reflection points are also estimated by applying the superresolution estimation technique to delay profiles. Measurements were made at 2.3 GHz.
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Cooperative simultaneous localization and mapping by exploiting multipath propagation

IEEE Transactions on Signal Processing, 2016
An affordable and reliable indoor positioning is a highly needed service. Moreover, maps of the indoor environment are vital to many applications. In this paper, a method for joint localization and mapping using multipath delay estimates is developed.
Koivunen, Visa, Naseri, Hassan
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Multipath Propagation of Radio Waves in 3-Dimensional Terrains

Journal of Electromagnetic Waves and Applications, 2001
Summary: A 3-Dimensional (3D) deterministic wave propagation model is developed to study signal propagation in natural 3D terrains in the frequency range of VHF/UHF. The propagation model is based on the physical principles of Geometrical Optics (GO) and the Uniform Geometrical Theory of Diffraction (UTD).
Kam, K.-Y., Chew, L.-Y., Li, L.-W.
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Reverberation for Multipath Propagation in Urban Areas

The Journal of the Acoustical Society of America, 1973
The propagation of urban noise combines the transmission phenomena of reflection, scattering, and shielding to produce sound levels that are substantially different from those that would exist in an open terrain situation. When the source is elevated, the number of important contributing paths is generally less than four or five, and the reverberation ...
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Modelling and simulation of urban multipath propagation

15th International Conference on Microwaves, Radar and Wireless Communications (IEEE Cat. No.04EX824), 2004
A Suzuki distribution has proved useful for modelling fading-shadowing channels of urban multipath propagation. The Suzuki model, which has a complicated integral form, is accurately described. A method of generating Suzuki distributed random sequence is proposed.
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Target time smearing with short transmissions and multipath propagation

The Journal of the Acoustical Society of America, 2011
In active sonar the target echo level is often estimated with a propagation model that adds all multipath arrivals. If the (post-correlator) transmitted pulse is short compared to the multipath time spread then there is effectively an extra loss (which may be substantial) since only a few of the paths contribute to the target echo at any one instant ...
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A Statistical Model for Indoor Multipath Propagation

2009
The results of indoor multipath propagation measurements using 10 ns, 1.5 GHz, radarlike pulses are presented for a medium-size office building. The observed channel was very slowly time varying, with the delay spread extending over a range up to about 200 ns and rms values of up to about 50 ns. The attenuation varied over a 60 dB dynamic range.
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Multipath Propagation

IEEE Communications Magazine, 1984
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Analysis of spherical propagation models for multipath-propagation predictions

International Journal of Physics and Applications, 2020
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