Page 46 - ITU Kaleidoscope 2016

2016 ITU Kaleidoscope Academic Conference

Table 2. Boat Test Drive 4 Results
Antenna Distance covered Remarks
Height Signal level > -95dBm

35 ft. 17 KM Observed
60 ft. 24 KM Model
prediction
100 ft. 35 KM

4.2.1 Boat Test Drive 4 – Different Telecom operator with
dual technology
Another test drive was done with the government telecom
service provider BSNL, which had two GSM Towers (900
MHz) at Saswane and Borli Mandla, both at a height of 35
ft. These towers were approx.150-300 m from the coast.
BSNL modified the antenna to direct one sector towards Figure 10. Boat Test Drive 4 Results
Arabian Sea. etc.). On these towers, following configurations were done

to increase coverage.
Mobile signals originating from these towers had good - Tower Top BTS (Feeder less)
reception up to 17KM from the coast. The data was fed to - Std 33deg antenna – High Gain ~20.5 dBi
a modeler and based on the pattern learnt by it, it projected
that a tower height of 100 feet can give mobile signal range
of up to 35km. (see table 2) In addition to this, a new tower was erected and equipped
with the following equipment to achieve a continuous 30km
mobile signal reach along 120km coastline of Raigad.
An interesting pattern was observed from a tower situated - Tower erection, Installation of the tower top BTS
35KM from the signal test point (in the sea). It was found Or Remote Radio unit (RRU)s and Feeder cables
that the Chirner tower (LAT 18.8675deg, LONG
73.07471389deg) was situated at a hill of Mean Sea Level - Antennas – MRFU V2 900MHZ CDMA
(MSL) height of 240 m. The antenna height of the BTS (SUPPORT 4 TRX, 20W TOC,25MHZ IBW)
was 30m. Hence, due to a height of the 270 m, the signal - Power, Diesel Generator, Microwave Link
was observed at the distance of 35KM (fig. 10). - Installation and commissioning
- IP Clearance, Site RFI, WPC certification
The data collected helped in analysis on what parameters
can affect the range of the signal availability. Some of the 4.3.1 Investment for a self-sustainable
parameters are: An estimated 13.7million Indian Rupees was needed to
- Mobile technologies (GSM vs. CDMA) modify and build these seven sites to start the mobility
- Spectrum availability (800KHz vs 1800 KHZ) signal up to a range of 30KM or so. This service benefited
- Height of the tower on which the BTS (Base approximately 11,620 fishermen families in Raigad and
Station Transceiver Sub system) hence, this investment translated to Rs. 98 (i.e. $2 USD) per
- Type of the BTS month per family for a year. This gives a very positive
reason on why these investments can break-even in a year
- Feed antenna length, Type of antenna and can become self-sustainable within two years.
- Antenna angle, Antenna radiation power level
- Type of handsets

4.3 Tower installation and commissioning

TTL surveyed the Raigad districts mobile towers and
picked up 7-8 sites where work needs to be carried out to
expand the signal up to 30+ KM in the sea (fig.11). To
create a mobile network offering services towards sea, they
needed to create “physical structure (called tower)”, install
the BTS , antenna , power supply units, and other network
components on it. Building new towers could have
escalated the cost and hence, TTL searched and found six
existing towers which fairly met the required specification Figure 11. Planned locations of towers and "digital
(such as 200 to 500 m from the coast, 40 m height or so, highway" in sea

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