Tuesday, December 10, 2013

Site Survey

Roof Top Site Survey

Few steps involved in this process and they are listed below.
  • Visibility/Availability


Due to nearby buildings some areas may not get covered. When signals gone through a wall 10 dB loss will be there. And we also note down possible locations to put our site and cabin of the site.

  •   Near Field and Far Field obstruction
In order to connect the site to the transmission network, there should be Line of Sight (LOS) between the existing sites and the proposed new site location. During the site survey we should check for the obstructions in both near field and far field.

  •   Access path
This is important in future maintenance. If there is a proper access path, it will make maintenance Engineers job easier.

  •   Power
Whether commercial power is available or not.
  •   150-200 m clearance from high tension line
  •   Obstruction from the same building



If this equation H > D/2 satisfied it is acceptable. Otherwise main lobe will be obstructed
from the same building.

  •   Then reference photographs of the site location are taken, these photographs will include:

*Visibility of the area from the site location (including panoramic photographs)
*Measured land area for the proposed site location
*Accessibility/Access path to the site location
*Availability of the Commercial power
*Terrain conditions of the land
*Neighboring buildings

  • Detailed sketch of the location is drawn
This sketch should include: Geo-graphical north referring to the drawing,  Access to the site location,  proposed  sit  location  of  the  selected  land,  landmarks  (nearby  buildings,  houses, power lines, trees).

 Deviations in a sharing site

In addition to the normal site survey process, in this process the BTS cabins are planned to install in other operator‟s site location premises. Therefore a suitable location with required dimensions (i.e. 16 ft X 12 ft) is measured. In selecting a cabin location we have to consider the distance from the existing site, cable ladder of the existing site etc.

 Green Field Site Survey

Majority  of  Green  field  sites  are  set  up  in  rural  areas.  There  are  few  deviations  from  the above mentioned Site  Survey process exists when we consider a GF site. And they are: need to conduct a soil test, and availability of commercial power. Also we have to consider the terrain condition. Other things are same as the roof top site survey.


 Technical Site Survey (TSS) Form


After completing the surveying process, TSS form was prepared for each new site.  And this form is then handed over to the PROJECTS section to proceed with the project.  TSS  form should include the following details.
  •  General Data of the site (Site name, Site Identification Code (SIC), etc.)
  •  Geo-coordinates of the site location
  •  For Roof Top sites : 
 *Height of the building
 *Microwave planning data: Azimuths and distance to three nearest microwave points. 

  • For Green Field site :
*Tower type : self-support / COW
*Tower height : 60 m/ 45 m/ 30 m
  • Location planning data : coverage objective, coverage area and distances  to  adjacent sites
  • BTS antenna related data;
*Antenna model e.g. 90 Dual Band
*Installation height of the antenna
*Antenna azimuths
*Mechanical and electrical tilt
  • Clearance to the nearest high tension line
  • Terrain condition (for Green Field sites)
  • Power availability
  • Column/beam under pole location (for Roof Top sites)
  • Site location marked on a map