Propagation loss models Lab 4 Engr. Mehran Mamonai

Terrain, Clutter, Morphology Traffic Load Prediction BS Performance Parameters Cell site 、 Propagation model 、 Antenna system Model correction System Simulation Meet requirements of the operator ？ Link Budget Output reports PN Planning RF Interference Analysis YN Source ZTE ‘CDMA network planning’ Network planning process

Mobile BTS Cable loss Antenna gain Path loss Antenna gain Cable loss Margin Link budget model Calculate all the gains and losses you have over a link See figure on next slide Determine allowable maximum path loss Determine optimal cell radius

This is part of a simplified link budget calculator for GSM. The figure on the left shows the calculator for the maximum allowable path loss The figure below shows the calculator for optimal cell size

Okumura’s model The model has been developed from an extensive series of field trials, which were undertaken in and around Tokyo under the following conditions: Frequencies from 100 MHz to 3 GHz Distances from l km to 100 km Different terrain conditions: urban, suburban, rural with various degree of undulation Effective base antenna height from 30 m to l000 m Vehicular antenna height from lm to l0 m Other factors such as the orientation of streets and the presence of mixed land-sea paths.

The basis of the method is to determine the free-space path loss at a receiver located d km, from a transmitter and then add that value to the median attenuation, A μ, in urban area over quasi-smooth terrain with a base station effective antenna height, h te, of 200 m and a mobile antenna height, h re, of 3 m. The free space path loss at a frequency, say, f MHz can be determined using the following equation: where G T and G R are the gain of the transmitting and receiving antennas, respectively Correction factors are introduced to account for propagation path characteristics

Hata model In an attempt to make the Okumura model easy to apply, Hata established empirical mathematical relationships to describe the graphical information given by Okumura Hata's formulation is limited to certain ranges of input parameters and is applicable over quasi-smooth terrain Restrictions of Hata-Okumura model BS height: 200 m MS height: 100 m Frequency: 500 – 1500 MHz Distance between MS & BS: Km

Variables MHz 1500 – 2000 MHz c1c c2c f : Carrier frequency (MHz) h b : Base station antenna height 30 m ≤ h b ≤ 200 m h m : Mobile station antenna height a(h m ) : Mobile antenna gain function c 1 & c 2 are correction factors Hata Urban

Variables MHz 1500 – 2000 MHz c1c c2c f : Carrier frequency (MHz) h b : Base station antenna height 30 m ≤ h b ≤ 200 m h m : Mobile station antenna height a(h m ) : Mobile antenna gain function c 1 & c 2 are correction factors C m : 3 dB Hata Dense urban

Hata model for Sub-urban Hata model for Quasi-open rural Hata model for Open Remember! Propagation models will never give accurate path loss In fact it is only a prediction for the path loss

Today’s Lab task Make function files for Hata’s model There would be five function files Use these files to find the Loss incurred by the radio signal under the following circumstances Operating frequency: 910 MHz Distance between BS & MS: 2 Km BS height: 45 m MS height: 1.5 m Attach the function files in the handout! See next slide for more…

Using these codes, plot the following graph