propagation loss models lab 4 engr. mehran mamonai

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Propagation loss models Lab 4 Engr. Mehran Mamonai

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Page 1: Propagation loss models Lab 4 Engr. Mehran Mamonai

Propagation loss modelsLab 4

Engr. Mehran Mamonai

Page 2: 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

Y N

Source ZTE ‘CDMA network planning’

Network planning process

Page 3: Propagation loss models Lab 4 Engr. Mehran Mamonai

Mobile BTSCable loss

Antenna gain

Path loss

Antenna gain

Cable loss

Margin

Link budget model

Calculate all the gains and losses you have over a linkSee figure on next slide

Determine allowable maximum path lossDetermine optimal cell radius

Page 4: Propagation loss models Lab 4 Engr. Mehran Mamonai

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

Page 5: Propagation loss models Lab 4 Engr. Mehran Mamonai

Okumura’s modelThe 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 GHzDistances from l km to 100 kmDifferent terrain conditions: urban, suburban, rural

with various degree of undulationEffective base antenna height from 30 m to l000 mVehicular antenna height from lm to l0 mOther factors such as the orientation of streets and

the presence of mixed land-sea paths.

Page 6: Propagation loss models Lab 4 Engr. Mehran Mamonai

The basis of the method is to determine the free-space path loss at a receiver located dkm, from a transmitter and then add that value to the median attenuation, Aμ, in urban area over quasi-smooth terrain with a base station effective antenna height, hte, of 200 m and a mobile antenna height, hre, of 3 m. The free space path loss at a frequency, say, fMHz can be determined using the following equation:

where GT and GR are the gain of the transmitting and receiving antennas, respectively

Correction factors are introduced to account for propagation path characteristics

Page 7: Propagation loss models Lab 4 Engr. Mehran Mamonai

Hata modelIn 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 modelBS height: 200 mMS height: 100 mFrequency: 500 – 1500 MHzDistance between MS & BS: 1 - 20 Km

Page 8: Propagation loss models Lab 4 Engr. Mehran Mamonai

Variables

150 - 1000 MHz

1500 – 2000 MHz

c1 69.55 46.3

c2 26.16 33.9

)(log)}(log55.69.44{)()(log82.13)(log 1010101021 dhhahfccL bmbHU

f : Carrier frequency (MHz)

hb : Base station antenna height 30 m ≤ hb ≤ 200 m

hm : Mobile station antenna height

a(hm) : Mobile antenna gain function

c1 & c2 are correction factors

)8.010log56.1()7.0log1.1()( cmcm fhfha

Hata Urban

Page 9: Propagation loss models Lab 4 Engr. Mehran Mamonai

Variables

150 - 1000 MHz

1500 – 2000 MHz

c1 69.55 46.3

c2 26.16 33.9

mbmbHU CdhhahfccL )(log)}(log55.69.44{)()(log82.13)(log 1010101021

f : Carrier frequency (MHz)

hb : Base station antenna height 30 m ≤ hb ≤ 200 m

hm : Mobile station antenna height

a(hm) : Mobile antenna gain function

c1 & c2 are correction factors

Cm : 3 dB

Hata Dense urban

97.4)}75.11({log2.3)( 210 mm hha

Page 10: Propagation loss models Lab 4 Engr. Mehran Mamonai

Hata model for Sub-urban

Hata model for Quasi-open rural

Hata model for Open

Remember! Propagation models will never give accurate path lossIn fact it is only a prediction for the path loss

4.5)}({log2 22810 f

HUHS LL

94.35)(log33.18)}({log78.4 102

10 ffLL HUQO

94.40)(log33.18)}({log78.4 102

10 ffLL HUO

Page 11: Propagation loss models Lab 4 Engr. Mehran Mamonai

Today’s Lab taskMake function files for Hata’s model

There would be five function filesUse these files to find the Loss incurred by the

radio signal under the following circumstancesOperating frequency: 910 MHzDistance between BS & MS: 2 KmBS height: 45 mMS height: 1.5 m

Attach the function files in the handout!See next slide for more…

Page 12: Propagation loss models Lab 4 Engr. Mehran Mamonai

Using these codes, plot the following graph