Path Loss Analysis between the north and the
south of Mauritius with some Existing Models for
Digital Television Broadcasting for Summer
Season at UHF Bands
Armoogum V., Member IEEE, University of Technology, Mauritius
Soyjaudah K.M.S., University of Mauritius, Mauritius
Mohamudally N., University of Technology, Mauritius
Fogarty T., London South Bank University, England
Tel: (230) 234 76 24, (230) 799 16 21
E-mail: varmoogum@utm.intnet.mu
Abstract - After the official launching in October 2005 of Digital
Terrestrial television (DTT), plans were made to carry out field
measurements across the island. Field strength, Carrier-to-Noise
Ratio and Bit-Error-Rate were measured at two antenna heights
(4 m and 6 m) both in the north and south of Mauritius at UHF
Bands (470 to 862 MHz). In this paper, we compare the measured
path loss obtained for the sub-urban northern area with that for
the rural southern area and then with four propagation models,
that is, Free-Space, Lee, Hata and Extended COST-231. Firstly,
for both areas, the results show that the path loss is not constant
at various locations for a constant distance around the respective
base station showing that the terrain of Mauritius is irregular.
Moreover, for the same antenna height, the path loss is higher in
the south than in the north by 5 dB to 20 dB depending upon the
distance from the station. The effects of the slow fading effect
(shadow) and fast fading effect are more pronounced in the south
than in the north, causing higher probability of signal errors.
Secondly, we found that Lee and Free Space models are not in
agreement with the values obtained for both regions. However,
observations show that Hata and Extended COST 231 models give
better agreement and hence, can be used to model areas in
Mauritius.
Index Terms - Bit Error Rate, Carrier to Noise ratio, COFDM,
DTT, DVB-T, Field Strength, Multiplexing, Path Loss,
Propagation Model.
I. INTRODUCTION
Mauritius is a tropical island in the Indian Ocean, located in
the Southern Hemisphere. Mauritius has two kinds of climate.
Below the 400-meter level on most of the windward
(southeastern) side of the island and below 450 meters on the
leeward side, a humid, subtropical climate prevails. Above
these altitudes, the climate is more temperate, but there is no
sharp break, and variations in exposure, altitude, and distance
from the sea produce a wide range of patterns. The island has
two seasons. The hot and wet summer lasts from November
through April. February is the warmest month with highest
temperatures of 38 ºC in the lowlands and 34 ºC on the plateau.
Winter is cool and dry, influenced by the steady southeasterly
trade winds. July is the coolest month and has average
temperatures of 22 ºC in the lowlands and 16 ºC in the plateau.
Rainfall is abundant, ranging from 90 cm per year in the
western lowlands to 500 cm in the tableland and an average of
200 cm per year overall. Humidity is frequently above 80
percent. The whole terrain is irregular and with numerous
mountains and hills and gorges. The area is about 1860 km
2
.
The central plateau, which is not really flat, gradually rises
towards the south west where it reaches its highest point at 800
m with the Piton de la Rivière Noire peak. This plateau is
surrounded with the primary crater in the form of a chain of
mountains and some isolated peaks.
Buildings, houses, sugar cane plantation and trees are
scattered in the north part of Mauritius while the south is
mainly covered by large areas of sugar cane field, dense forests
and range of mountains and gorges. In this paper, we classify
the north as suburban (76%) and the south as rural will apply
the category of the terrain mentioned in the ITU-R
Recommendations of 1997 [1].
Field strength analysis and path loss analysis are research
areas over the past four decades and now have become very
important when the world is moving towards the digital era.
Prasad and Iqbal et al. [2][3] have carried out research works
on path loss analysis using several old models in Southern
India using VHF/UHF bands [4]. In 2005, the above mentioned
authors have done an intensive research works and have used
the Perez-Vega and Zamanillo’s model [5]. Arinda et al. [6][7]
have done similar works in Spain on digital TV broadcasting.
We have carried some preliminary study on field strength with
few measuring data in the north [8] and have studied the
variation of the path loss using some models [9]. The
observations of the two above-mentioned papers show firstly
that in the north at a distance of 5 km from the base station, the
power level was high enough to decode picture to achieve a
BER lower than 2x10
-4
. However, the signal strength
decreases by 20 dB in the region of near 10 km from the base
station as the cell covered by the base station does not include
this region. Secondly, observation shows that Hata model is
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