9.2 ANTENNA LOCATIONS

It is difficult to select an optimum antenna location for a base station. First the signal strength coverage at a distance such as 13 km from a base station antenna does not exhibit a uniform pattern. This irregular pattern is due to the irregular terrain configuration. Another important aspect is avoiding interface. Therefore a plan for a base-station antenna location should consider both its coverage range and its interference with other antennas. In a large system all the potential base-station location should be considered at the same time. If one base station is moved to a different position, then all the other station locations are affected.

There are several steps in choosing a base-station location :
1. First, decide on a reception level at the cell boundary. This is bale on the features of the mobile trans-receiver an the system performance required.
2. Choose a location where land is usually available for a first choice base station.
3. Follow the new path-loss prediction midel to make a point-to –pint predicting. An equal-strength contour can be drawn on the map.
4. Choose other locations and draw -100-dBm equal-strength contour of them. The equal-strength contours of all locations should have roughly the same portion overlapping as shown in fig. A.
5. Avoid the equal-strength contour condition shown in Fig. B.