outdoor indoor propagation

16
PROPAGATION MODELS INDOOR OUTDOOR LOG-NORMAL LOG-DISTANCE

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Outdoor indoor Propagation

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Page 1: Outdoor indoor Propagation

PROPAGATION MODELS

INDOOROUTDOOR

LOG-NORMALLOG-DISTANCE

Page 2: Outdoor indoor Propagation

BASIC DIVISION

Different models have been developed, to meet the needs of realizing ,the propagation behavior in different conditions.

Types of models for radio propagation include: Models for indoor applications Models for outdoor applications

Page 3: Outdoor indoor Propagation

Outdoor Propagation Models There are a number of mobile radio propagation

models to predict path loss over irregular terrain.

These methods generally aim to predict the signal strength at a particular sector.

But they vary widely in complexity and accuracy.

These models are based on systematic interpretation of measurement data obtained in the service area.

Page 4: Outdoor indoor Propagation

OUTDOOR APLLICATION MODELS

Ground wave propagation models Sky wave propagation models Environmental Attenuation models Point-to-Point propagation models Terrain models City Models

Page 5: Outdoor indoor Propagation

Models for outdoor attenuations Near-earth propagation models

Foliage models Weissberger's modified exponential decay model Early ITU Model Updated ITU model

One Woodland Terminal Model Single Vegetative Obstruction Model

Terrain models Egli Model Longley–Rice model ITU Terrain Model

Page 6: Outdoor indoor Propagation

Examples City models

Young Model Okumura Model Hata Model for Urban Areas Hata Model for Suburban Areas Hata Model for Open Areas COST Hata model Area to Area Lee Model Point to Point Lee Model

Band-specific models 2.4 GHz (ISM Band, of particular interest for WiFi)

Green-Obaidat Model[1

Page 7: Outdoor indoor Propagation

Examples of Outdoor Models

Longley-Rice Model Durkin’s Model Okumura’s Model Hata Model PCS extension to Hata Model Walfisch and Bertoni

Page 8: Outdoor indoor Propagation

Indoor Propagation ModelsIndoor Propagation Models

Indoor radio channel differs from traditional mobile radio channel in: distances covered are much smaller variability of the environment is greater for a much

smaller range of T-R separation distances

It is strongly influenced by specific features, such as layout of the building construction materials building type

Page 9: Outdoor indoor Propagation

Models for indoor attenuations

ITU Model for Indoor Attenuation

Log-distance path loss model

Page 10: Outdoor indoor Propagation

Log-Normal Distribution

It describes the random shadowing effects which occur over a large number of measurement locations which have the same T-R separation,but have different levels of clutter on the propagation path.

The random effects of shadowing are accounted for using the Gaussian distribution

In practice, the values of n and σ are often computed from measured data, using linear regression

Page 11: Outdoor indoor Propagation
Page 12: Outdoor indoor Propagation

)(

)(PrdP

QdP rr

The probability that the received signal level will exceed a certain value γ can be calculated from the cumulative density function as

Can be used to determine the percentage of coverage area in cellular systems.

Applications

Page 13: Outdoor indoor Propagation

•Both theoretical and measurement-based propagation models indicate that average received signal power decreases logarithmically with distance, whether in outdoor or indoor radio channels.

• The average large-scale path loss for an arbitrary T-R separation is expressed as a function of distance by using a path loss exponent, n.

Penetration Thru Buildings/ Log-Distance Path Loss Model

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