Challenges Ahead!

India has crossed the 220-mn mark in mobile subscriber base,
with approximately 30% active coverage of the total geographical area of the
country.

With approximately 8 mn subscribers being added each month, the
target under reach is 500 mn subscribers by 2010, and 650 mn or more by 2012.

To achieve the phenomenal coverage and subscriber growth of
mobile telephone users, nearly 70% of the country's area still needs to see
setting up of the mobile network infrastructure.

We are going to talk about mainly two very visible components of
the passive part of the telecom infrastructure-towers and shelters. Aggressive
plans are afoot to install as many towers/shelters in as little time as
possible. The total investment envisaged to create this vast countrywide network
of additional 250,000 towers is Rs 66,000 cr or $16.5 bn.

All this euphoria of telecom development, though justified, is
likely to be marred by various concerns-environmental, functional and
operational, and economical and financial. These concerns arise out of the fact
that all future expansions will be concentrated toward the rural and remote
parts of India, with its own unique set of issues.

Towers apart, the bigger issue is related to shelters, which
house the sensitive electronic components of the mobile networks.

Power source is another major issue to be concerned about,
characterized by either non-availability or partial availability of power grid
connection. This means that each tower/shelter cluster requires its own
high-capacity diesel-run generators leading to concerns ranging from security
issues to logistics of fuel supplies, running and maintenance and operational
costs and, above all, the fear of environmental degradation.

Solutions for Housing

The performance of the telecommunication system depends on the reliability
of housing and apparatus. The concept of "housing" means the
sheltering structure optimized for the protection of electronic equipment
against ambient stress and vandalism.

This necessarily means that the internal conditions have to be
adapted to the outer conditions to obtain an ambient internal
temperature/humidity suitable for the effective protection of the equipment and
the apparatus. One of the ambient stresses the equipment may be subject to is
thermal stress.

Air conditioning is, without doubt, the most difficult form of
protection.On the other hand, the major cause of telecommunication equipment
failure is overheating of components used.

Each solution to be properly designed, cannot ignore the
evaluation of initial costs of the system; an analysis of operational costs;
available energy, (quantity and type, cost, reliability); the dissipated energy
(if continuous or intermittent); the accessibility of the station.

The primary objective, therefore, is to create maximum energy
efficiency and energy savings. And it is here that the passive (PCS) or
semi-passive cooling systems (semi-PCS) can be useful in gaining maximum
reliability (MTBF) and functionality (MTTR), removing most direct and indirect
costs due to operation, maintenance, replacements, among others.

Passive Housing

A housing (shelter) is considered to be "passive" when the energy
necessary for its conditioning is supplied entirely by the thermal energy
available from the natural alternation between day and night, and the seasons.
The types and usage of passive housing are given below:

Passive Systems with Storage: These are used when the
maximum internal temperature is less or equal to the maximum external
temperature and the external temperature has a certain day-night range. It is a
mandatory solution for desert areas, but can also be extended to temperate
zones.

Passive Systems without Storage: These are used when the
maximum internal temperature is higher than the maximum external temperature.
These are typically used for equatorial zones.

Semi-Passive Housing

A housing is considered to be "semi-passive' when the energy
necessary for its conditioning is not supplied entirely by the thermal energy
available from the natural alternation between day, night, and the seasons. The
types and usage of semi-passive housing are given below:

Semi-passive Systems with Storage: These are used when the
maximum internal temperature is less than the maximum external temperature. It
is a typical solution for desert and temperate areas; it enables a more
efficient conditioning even with higher power dissipation than that managed by
the passive system. It is also more adaptable for conditioning of apparatus
rooms in buildings.

Semi-passive Systems without Storage: These are used when
the maximum internal temperature is higher than the maximum external
temperature.

Passive Self-Ventilated Housing

In this case, the shelter is not hermetic or sealed from the external
ambient conditions. Thermal control is made by natural convection between the
cooler external air and the internal warmer air. The device that enables
communication between the internal and the external ambient is of the passive
type. These shelters can be used in temperate and equatorial zones when the
internal temperature is higher than the external temperature.

Active Conditioned Housing

A housing is considered to be "active" when the energy necessary
for its conditioning is supplied entirely by available electrical power. This
can be used in all climatic areas and is typically in use in India, leading to
issues under consideration.

Hybrid Conditioned Housing

Typical application is for high-capacity solar powered GSM stations since it
can conveniently utilize the exceeding electrical power available during the
hottest hours. The active system intervenes as a backup of the passive one,
lowering the peaks of excess temperature due to thermal stress and/or
exceptional power consumption. This can be used in desert and hot temperate
areas.

Conclusively, completely integrated solutions are available that
can mitigate a variety of challenges that telecom operators are staring at, in
their quest for universal coverage. These solutions are customized and designed
as per physical locations, environmental and climatic conditions, ensuring that
failures related to standard form solutions, due to even the slightest local
variations, are done away with.

Amitabh Singhal, director,
VCON Services,and

Enzo Celant, CEO, Celant.tel, Italy

vadmail@cybermedia.co.in

Parts of the article reproduced with permission
from Intellectual Handbook by Dr Enzo Celant