This document discusses different radio propagation models for both indoor and outdoor environments. It provides examples of common outdoor propagation models including the Longley-Rice model and Hata model. It also discusses indoor propagation models and key factors that influence indoor radio signals, such as building layout and construction materials. Common indoor path loss models include the log-distance path loss model and ITU indoor attenuation model. Radio propagation is influenced by factors like distance, environment, and signal penetration through buildings.

1. PROPAGATION MODELS INDOOR OUTDOOR LOG-NORMAL LOG-DISTANCE

2. 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

3. 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.

4. OUTDOOR APLLICATION MODELS Ground wave propagation models Sky wave propagation models Environmental Attenuation models Point-to-Point propagation models Terrain models City Models

5. 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

6. 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

7. Examples of Outdoor Models Longley-Rice Model Durkin’s Model Okumura’s Model Hata Model PCS extension to Hata Model Walfisch and Bertoni

8. Indoor 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

9. Models for indoor attenuations ITU Model for Indoor Attenuation Log-distance path loss model

10. 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

12. Applications 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 .

13. Penetration Thru Buildings/ Log-Distance Path Loss Model 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.

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