No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Matrix based ray-tracing model for indoor propagation
Abstract
This paper presents a fast and accurate method for indoor signal strength prediction. Method is based on pathloss precalculation for the whole coverage area of an access point in free space. Resulting matrix and object masks are used to calculate signal strength for all points simultaneously minimizing the number of needed calculations and reducing prediction time significantly. Also discussed is the upgrade to 3D prediction.
... The first uses a discrete method with multiple points. It is important to choose a sufficient number of points, depending on wavelength, in order to find maxima and minima, especially if the measurements are performed indoors, as in Zrno and Šimunić [7]. The second method is a continuous scan across measurement points, where it is important to choose an appropriate measuring area. ...
Europe is the only region in the world with common legislative acts regulating exposure to electromagnetic fields (EMF) for both the general public and workers. Council Recommendation 1999/519/EC deals with the limitation of exposure of the general public to EMF (0 Hz-300 GHz). Directive 2004/40/EC regulates the minimum health and safety requirements regarding the exposure of workers to the risks arising from EMF. This paper discusses the general application of existing standards and recommendations in measurement techniques for determining compliance of measured exposure limit values and action values with those defined in 2004/40/EC.
Mobile ad-hoc networks (MANET) operate like self organizing entity. The mobile nodes are operate in a host as well as in a router and dynamic topology. In MANET every network node operates autonomously. It has limited resources like power, bandwidth and storage capacity. Selection of a propagation model plays the vital role of application possibilities in MANET. In this paper, calculations have been performed for three propagation models: Two-ray ground, COST 231 and Okumura-Hata model. The paper shows the impact of these propagationmodels based onAd-hoc on-demand distance vector (AODV) protocol at 1.5GHz frequency, varying transmitted power and number of nodes. This paper also studies effects of the propagationmodels with the conclusion of choosing the most accurate propagation model. Okumura-Hata propagation model shows better results at 1.5GHz frequency as compared to COST 231 and Two-ray ground model in open space using Network Simulator (NS 2.35). Two-ray ground propagation model shows better results with varying transmitted power and number of nodes as compared to COST 231 and Okumura-Hata model.
With the introduction of wireless broadband services in indoor
environments there is a growing interest in propagation models for the
mobile radio channel inside buildings. Because of the increasing
transmission rates propagation models should be able to calculate the
field strength coverage as well as the wideband properties for these
indoor scenarios. This paper presents a new ray optical approach, which
enables the prediction of field strength, delay spread and impulse
response within a very short computation time. Additionally, simulation
results gained with the new model are compared to measurements of the
different wideband channel parameters
The application of several ray-tracing techniques, in combination
with the uniform theory of diffraction, is presented for efficient
prediction of propagation in the UHF (communication) band in an indoor
environment. First, we improve the computational efficiency of the
two-dimensional (2D) ray-tracing method by reorganizing the objects in
an indoor environment into irregular cells. Second, by making use of the
two-dimensional ray-tracing results, a new three-dimensional (3D)
propagation-prediction model is developed, which can save 99% of the
computation time of a traditional three-dimensional model. This new
hybrid model is more accurate than two-dimensional models, and more
efficient in computing the path loss to any point in the building than
traditional three-dimensional models. In this model, reflection and
refraction by layered materials, and diffraction for the corners of the
walls, are considered. A patched-wall model is used to improve the
accuracy of prediction in the method. Finally, a comparison between
simulation and measurements shows good agreement
A three-dimensional (3-D) propagation model, combined with a
patched-wall model, has been developed to predict radio loss in a
corridor environment. The ray-tracing technique is used and combined
with the ray-fixed coordinate system to simplify the computations of
transmission, reflection, and diffraction coefficients in 3-D space. The
computed path loss is compared with the measured value of 900-MHz and
2.44-GHz radio propagation along a hallway and gives a reasonable
agreement. It is also found that the fields transmitted through the
interior walls give the major contribution to the received field when
the radio path lies around a corner
Site Engineering for Indoor Wireless Spread Spectrum Communicationsc
- E Pop
- V Croitoru
- R Antohi
Mikrovalne komunikacije
- D Šimunić Skripta