This document summarizes key propagation models including Okumura, Hata, and COST231 models. It describes the models' parameters and equations. The Okumura model is empirical and based on extensive measurements in Japan. It accounts for factors like frequency, distance, and antenna heights. The Hata and COST231 models extend Okumura's validity to other frequencies and environments through curve-fitting. The document also explains how to extract data from the models' graphs using a web tool and simulate the models in MATLAB.

1. FBE104 Wireless Communications and Mobile Systems
KOCAELI UNIVERSITY
Graduate School of
Natural and Applied Sciences
Prepared By: Mohammed ABUIBAID
Email: m.a.abuibaid@gmail.com
Submitted to: Dr. Kerem KÜÇÜK
Electronic and Communication Engineering
OKUMURA, HATA and COST231 Propagation Models
AcademicYear
2015/2016

2. Presentation Outline
1. Kinds of Propagation Models
2. Models of Different Types of Cells
3. Web Plot Digitizer Tool
4. Study of the parameters fc, d, 𝒉 𝒃 , 𝒉 𝒎 and Coverage
Environments for each of OKUMURA, HATA and COST231
5. MATLAB Simulation

3. Empirical models
Three kinds of models Semi-deterministic models
Deterministic models
Empirical models : based on measurement data, simple (few parameters), use
statistical properties, not very accurate
Semi-deterministic models : based on empirical models + deterministic
aspects
Deterministic models : site-specific, require enormous number of
geometry information about the cite, very important computational effort, accurate
Propagation Models

4. Models of Different Types of Cells :
 Macro-cell path loss models
Empirical models: Okumura-Hata model, COST 231-Hata model
Semi-empirical models: COST 231-Walfisch-Ikegami
Deterministic models: Plane earth model, Ikegami model
 Microcell path loss models
Empirical model: Dual slope empirical model
Deterministic model: Two-ray model
 Pico-cell path loss models
Empirical model: Wall and floor factor models - ITU-R models
Semi-empirical model: COST231 line-of-sight model

5. Okumura Model
 Widely used for signal prediction in urban areas
 Applicable for:
• Frequency f: 150 MHz to 1920 MHz (it is typically extrapolated up to 3000 MHz)
• Distance d: 1 km to 100 km
• Transmit antenna effective height : 30 m to 1000 m and Mobile Antenna height 1 m to 10 m
 Based on extensive measurements
 Technique
• Find free space path loss, LF (using equation)
• Determine median attenuation relative to free space Amu(f,d) (from curves)
• Add correction gain factors for transmitter and receiver antenna heights (from curves or using
their equations) and area gain factor (from curves)

6. Okumura Model
 𝑳 𝟓𝟎 𝒅𝑩 : the 50th percentile (i.e., median) value of propagation path loss between the TX and
RX expressed in dB
 𝑳 𝑭 : is the free space propagation loss in dB
 𝑨 𝒎𝒖(f, d) : the median attenuation relative to free space additional losses in dB due to
propagation in urban environment when TX and RX at referenced heights.
 𝑮(𝒉 𝒕𝒆) : the base station antenna height gain factor in dB
 𝑮(𝒉 𝒓𝒆) : the mobile antenna height gain factor in dB
 𝑮 𝑨𝑹𝑬𝑨: the gain due to the type of terrain in dB

7. Okumura Model (free space loss)
 d Distance between the TX and RX in km
 f Operating frequency in MHz
 𝑮 𝒕 TX antenna gain (linear)
 𝑮 𝒓 RX antenna gain (linear)
 The remaining terms of Okumura Model are provided in a graphical form as the family of curves.

8. Okumura Model (Basic Median Attenuation 𝑨 𝒎𝒖(f, d) )
 It models additional propagation losses due to
the signal propagation with these referenced
conditions:
- Terrestrial Urban environment over a quasi-smooth
terrain.
- Base station Effective antenna height 𝒉 𝒕𝒆 = 𝟐𝟎𝟎 𝒎
- Mobile antenna height 𝒉 𝒓𝒆 = 𝟑 𝒎.
 If the actual heights of the TX and RX or the
propagation area type differ from those
referenced, the appropriate correction needs to
be added.

9. Okumura Model (Base Station Effective Height Gain 𝑮 𝒉 𝒕𝒆 )
 At the effective height of 200m, all curves meet and no
correction gain is required (𝑮 𝒉 𝒕𝒆 = 𝟎 𝒅𝑩)
 Base station antennas above 200m, introduce positive
gain and antennas lower than 200m have negative gain
factor.
 The parameter of the family of the curves is the
distance between the transmitter and receiver.
 Okumura found that 𝑮 𝒉 𝒕𝒆 varies at a rate of 20
dB/decade for effective heights between 30 m and
1000 m

10. Okumura Model (Effective Transmitter Antenna Height)
 The terrain is averaged along the direction of radio path over the distances
between 3 and 15 kilometers.
 Effective antenna height is determined as the difference between the height of
the BTS antenna and the height of the average terrain.

11. Okumura Model (Mobile Height Gain Factor 𝑮 𝒉 𝒓𝒆 )
 All curves meet at the referent 3m horizontal coordinate.
 Higher antennas introduce gain and lower cause loss of
referent signal level.
 The parameter for this family of curves is operating frequency.
 Mobile height gain factor is also separated according to the size
of the city in two clusters: medium and large cities.
 Okumura found that 𝑮 𝒉 𝒓𝒆 varies at a rate of 10 dB/decade
for Mobile heights less than 3 m and varies at a rate of 20
dB/decade for Mobile heights between 10 and 3 m.

12. Okumura Model (Environment Gain 𝐺 𝐴𝑅𝐸𝐴)
 For the referent Urban terrain environment the
value of 𝐺 𝐴𝑅𝐸𝐴 = 0 𝑑𝐵.
 For Other terrain types; such as Suburban, Quasi-
Open and Open Areas, the value of 𝐺 𝐴𝑅𝐸𝐴 can be
read the curves.
 𝐺 𝐴𝑅𝐸𝐴 values represent a additional loss
correction factor due to propagation in different
than Urban environment.

13. Okumura Model (Optional Correction Factors)
 Some of the important terrain related corrections parameters are:
- Terrain undulation height Δh
- Isolated ridge height
- Average slope of the terrain
- Mixed land-sea parameter
 Once the terrain related parameters are calculated, the necessary correction factors can
be added or subtracted as required.

14. Okumura Model (Pros and Cons)
 Okumura's model is wholly based on measured data and does not provide any analytical
explanation.
 For many situations, extrapolations of the derived Curves can be made to obtain values
outside the measurement range.
 The validity of such extrapolations depends on the circumstances and the smoothness of
the curve in question.
 The major disadvantage is its slow response to rapid changes in terrain.
 The model is fairly good in urban and suburban areas, but not as good in rural areas.
 Common standard deviations between predicted and measured path loss values are
around 10 dB to 14 dB.

15. Web Plot Digitizer Tool
 WebPlotDigitizer is a free, online/offline tool to extract numerical data from plots, images and maps.
 WebPlotDigitizer release notes are available here. The user manual is available here.
This tool can be employed to read values form OKUMURA
Curves to use them in path loss calculations.

16. Okumura Model: Figure 1
 Variable Parameter:
d = [1 2 3 5 10 20 30 40 50 60 70
80 90 100]
Amu=[20.5 ….. 61]*
 Constant Parameters:
f=1000, hb=200, hm=3,
Urban
 The path loss increase
exponentially as the Tx,Rx
separation distance increase.
 *: This values are read from
Okumura Curves using Web
Digitizer Tool

17. Okumura Model: Figure 2
 Variable Parameter:
f =150.23, …. 1916.29*
Amu =28.15, …. 36.27*
 Constant Parameters:
d=20, hb=200, hm=3, Urban
Area.
 The path loss increase linearly
as the operating frequency
increase.
 *: This values are read from
Okumura Curves using Web

18. Okumura Model: Figure 3
 Variable Parameter:
hb = 30:0.5:1000
 Constant Parameters:
f=1000, d=20, hm=3, Amu=
32.9*, Urban Area.
 The path loss decrease
exponentially as the BS
Effective Height increase.
 *: This values are read from
Okumura Curves using Web
Digitizer Tool

19. Okumura Model: Figure 4
 Variable Parameter:
hm = 1:0.2:10
 Constant Parameters:
f=1000, d=20, hb=200,
Amu= 32.9*, Urban Area.
 The path loss decrease
exponentially as the MS
Antenna Height increase.
 *: This values are read from
Okumura Curves using Web
Digitizer Tool

20. Okumura Model: Figure 5
 Variable Parameter:
G_area = { G_suburban = 9.82,
G_quasi-open areas = 23.28,
G_open areas = 28.63 }*
 Constant Parameters:
f=1000, d=20, Amu= 32.9*,
hb=200, hm=3
 The path loss decrease linearly as
the coverage area change from
suburban to open areas.
 *: Theses values are read from
Okumura Curves using Web
Digitizer Tool

21. Okumura-Hata Model
 Simply, It represents a curve fitting of Okumura’s original results.
 Applicable for:
• Transmit antenna effective height : 30 m to 200 m and Mobile Antenna height 1 m to 10 m
• Frequency f: 150 MHz to 1500 MHz and TX RX Distance d: 1 km to 20 km
 In that implementation, the path loss is written as

22. Okumura-Hata Model ( 𝐚(𝐡 𝐦) , C Factor )
 The function 𝑎(ℎ 𝑚) and the factor C depend on the environment:
 𝒂(𝒉 𝒎) in suburban and rural areas is the same as for urban areas (small & medium-sized cities)

23. Okumura-Hata Model: Figure 6
 Variable Parameter:
d = 1:0.2:20
 Constant Parameters:
f=1000, hb=50, hm=3,
Enviro=Urban
 The path loss increase
exponentially as the Tx,Rx
separation distance increase.

24. Okumura-Hata Model: Figure 7
 Variable Parameter:
f = 150:20:1500
 Constant Parameters:
d=15, hb=50, hm=3,
Enviro=Urban
 The path loss increase
linearly as the operating
frequency increase.

25. Okumura-Hata Model: Figure 8
 Variable Parameter:
hb = 30:2:200
 Constant Parameters:
d=15, f=1000, hm=3,
Enviro=Urban
 The path loss decrease
exponentially as the BS
Effective Height increase.

26. Okumura-Hata Model: Figure 9
 Variable Parameter:
hm = 1:0.2:10
 Constant Parameters:
d=15, f=1000, hb=50,
Enviro=Urban
 The path loss decrease
linearly as the MS Antenna
Height increase.

27. Okumura-Hata Model: Figure 10
 Variable Parameter:
Environment = { Urban,
Metropolitan, Suburban, Rural
}
 Constant Parameters:
d=15, f=1000, hb=50,
hm=3, Enviro=Urban
 The path loss decrease
dramatically as the coverage
area change from
Metropolitan to Rural

28. Okumura-Hata Model (Pros and Cons)
 It was derived as a numerical fit to the curves published by Okumura. As such, the model
is somewhat specific to Japan’s propagation environment.
 It assumes that there are no dominant obstacles between the BS and the MS, and that the
terrain profile changes only slowly.
 Measurements have shown several disadvantages to the approach for effective antenna
height calculation. To circumvent the problem, some prediction tools examine
alternative methods for calculation of the effective antenna height.
 Parameter range does not encompass the 1800 MHz frequency range most commonly
used for 2G and 3G cellular systems. (This was solved by the COST 231-Hata model)

29. COST 231-Hata Model
 Extends the validity region of Okumura-Hata Model to 1500 - 2000 MHz range which
encompass the 1800 MHz frequency which is used for 2G and 3G cellular systems.
 COST 231-Hata Model defined by:
 C is 0 in small and medium-sized cities “Urban Areas”, and Suburban Areas.
 C is 3 in Metropolitan Areas.

30. COST231-HATA MODEL: Figure 11
 Variable Parameter:
d = 1:0.2:20
 Constant Parameters:
f=1800, hb=50, hm=3,
Enviro=Urban
 The path loss increase
exponentially as the Tx,Rx
separation distance increase.

31. COST231-HATA MODEL: Figure 12
 Variable Parameter:
f = 1500:20:2000
 Constant Parameters:
d=15, hb=50, hm=3,
Enviro=Urban
 The path loss increase
linearly as the operating
frequency increase.

32. COST231-HATA MODEL: Figure 13
 Variable Parameter:
hb = 30:2:200
 Constant Parameters:
d=15, f=1800, hm=3,
Enviro=Urban
 The path loss decrease
exponentially as the BS
Effective Height increase.

33. COST231-HATA MODEL: Figure 14
 Variable Parameter:
hm = 1:0.2:10
 Constant Parameters:
d=15, f=1800, hb=50,
Enviro=Urban
 The path loss decrease
linearly as the MS Antenna
Height increase.

34. COST231-HATA MODEL: Figure 15
 Variable Parameter:
Environment = { Urban,
Metropolitan, Suburban}
 Constant Parameters:
d=15, f=1800, hb=50,
hm=3
 The difference between
Urban/Suburban Areas and
Metropolitan is 3 dB.

35. References
[1] The Mobile Radio Propagation Channel, 2nd Edition by J. D. Parsons
[2] Wireless Communications Principles And Practice By Theodore S. Rappaport
[3] Math Works: http://www.mathworks.com/
[4] Web Plot Digitizer Tool: http://arohatgi.info/WebPlotDigitizer/

36. Mohammed Abuibaid
Live & Breathe Wireless