The line of sight for telecommunication antennas may be become obstructed due to:
 

• Man made obstruction such as building or hills or tress etc in the path of communication.
• Obstruction due to curvature of earth.
• Obstruction in the path can be overcome by increasing the height of the antenna i.e. mounting the antenna on the top of the tower of suitable height.
• Telecommunication towers are normally structural supports designed to survive the wind load of the area and the loads due to antennas.
• On the negative side – These towers, when operational will emit electromagnetic radiation. If the towers are installed in residential areas, then human living in the nearby area will be exposed to radiations. Hence, residential areas should be avoided, if possible.

The buyer must specify the following parameters, before asking for an offer from tower supplier.

• Height
• Expected loading on the tower
• Twist and Sway permitted
• Any constraint on geometry of towers

For details of structural parameters required to be specified, the answer of Q2 above.

Following could be the further necessary/optional parameters for supply of tower materials.

• Quantity of antenna interfaces required. Diameter & length of pipe should be specified.
• Length of horizontal cable ladder or gantry, with or without supports.
• Quantity of Aviation obstruction lights.
• Length of electric cable, if required.
• Quantity of lightening arrestor, if required.
• Size & length of down conductor for lightening arrestor required.
• No of grounding pits required.
• Size of ground electrodes.
• Paint required.
• Foundation bolts
• Foundation templates
• Nameplate/signage required for tower.

To achieve desired strength of tower, use of HSS (High Strength Steel) instead of normal mild structural steel will result in lighter tower.

In case of towers, operational costs do not depend on weight of tower. Hence no special advantage is obtained by using HSS. 

Not necessarily. It depends on:

• Weight of steel saved in tower by using high strength steel and
• Price differential between high strength steel and normal mild steel.