5 Best Practices for Antenna Downtilt & Physical Tuning

When a base station is installed, its antennas must be pointing in the right direction (Azimuth) and tilted downwards at the right angle (Downtilt) to cover the target area and avoid interference with neighboring cells.

If the downtilt is too small (antenna is pointing too high), the signal will overshoot the target coverage area and interfere with distant cells using the same frequency. This is called 'overshooting'. If the downtilt is too large, the signal coverage will be too small, creating coverage holes.

Downtilt consists of two components: Mechanical Downtilt (physically tilting the antenna bracket) and Electrical Downtilt (adjusting the phase of the antenna elements inside the housing, which can be done remotely via a Remote Electrical Tilt - RET motor).

RF engineers use trigonometry to calculate the initial downtilt. The formula depends on the antenna height (H) and the distance to the target cell boundary (D).