COST Hata model

The COST Hata model is a radio propagation model that extends the urban Hata model (which in turn is based on the Okumura model) to cover a more elaborated range of frequencies. It is the most often cited of the COST 231 models (EU funded research project ca. April 1986 – April 1996),^[1] also called the Hata Model PCS Extension.^[2]

COST (COopération européenne dans le domaine de la recherche Scientifique et Technique) is a European Union Forum for cooperative scientific research which has developed this model accordingly to various experiments and researches.

Applicable to / under conditions

This model is applicable to urban areas. To further evaluate Path Loss in Suburban or Rural Quasi-open/Open Areas, this path loss has to be substituted into Urban to Rural/Urban to Suburban Conversions. (Ray GAO, 09 Sep 2007)

Coverage

Frequency: 1500–2000 MHz
Mobile station antenna height: 1–10 m
Base station Antenna height: 30–200 m
Link distance: 1–20 km

Mathematical formulation

The COST Hata model is formulated as,

$L\;=\;46.3\;+\;33.9\log f\;-\;13.82\log h_{B}\;-\;a(h_{R},f)\;+\;[44.9\;-\;6.55\log h_{B}]\log d\;+\;C$

For suburban or rural environments:

$a(h_{R},f)\;=\;(1.1\log f\;-\;0.7)h_{R}\;-\;(1.56\log f\;-\;0.8)$

And for large cities:

$a(h_{R},f)\;={\begin{cases}\;8.29\;(\;\log _{10}({1.54h_{R}}))^{2}\;-\;1.1\;{\mbox{ , if }}150\leq f\leq 200\\\;3.2\;(\log _{10}({11.75h_{R}}))^{2}\;-\;4.97\;{\mbox{ , if }}200<f\leq 1500\end{cases}}$

$C\;=\;{\begin{cases}0\;dB{\mbox{ for medium cities and suburban areas}}\\3\;dB{\mbox{ for metropolitan areas}}\end{cases}}$

Where,

L = Median path loss. Unit: decibel (dB)

f = Frequency of Transmission. Unit: megahertz (MHz)

h_B = Base station antenna effective height. Unit: meter (m)

d = Link distance. Unit: Kilometer (km)

h_R = Mobile station antenna effective height. Unit: meter (m)

a(h_R) = Mobile station antenna height correction factor as described in the Hata model for urban areas.

Points to note

The European Co-operative for Scientific and Technical research (EUROCOST) formed the COST-231 working committee to develop an extended version of the Hata model. COST-231 proposed the following formula to extend Hata's model to 2 GHz. The proposed model for path loss is

L50(urban) = 46.3 + 33.9 log fc – 13.82 log hte – a (hre) + (44.9 – 6.55 log hte) log d + Cm where a(hre) is the correction factor for effective mobile antenna height which is a function of the size of the coverage area.

          0 dB for medium-sized city and suburban areas

Cm =

          3 dB for metropolitan centers

       The COST-231 extension of the Hata model is restricted to the following

range of parameters:

   f : 1500–2000 MHz
   hte :30m to 200m
   hre :1m to 10m
   d :1km to 20 km

Limitations

This model requires that the base station antenna is higher than all adjacent rooftops.

References

↑ http://www.cost.eu/domains_actions/ict/Actions/231 COST (European Cooperation in Science and Technology) website
↑ Final report for COST Action 231, Chapter 4