sector antenna

A typical sector antenna is depicted in the figure on the right.

It has several angularly-separated sector antennas as shown on the figures at right.

In a picture on the right, there are two sector antennas with different mechanical downtilts.

A sector antenna is a type of directional microwave antenna with a sector-shaped radiation pattern.

Such a construction is often called a sectorized antenna, though sometimes for brevity "sector antenna" is used as well.

One popular design of mobile phone antenna is the sector antenna, whose coverage is 120 degrees horizontally and about +-5 degrees from the vertical.

A reuse pattern of N/K denotes a further division in frequency among N sector antennas per site.

In case of N sector antennas on the same base station site, each with different direction, the base station site can serve N different sectors.

To increase or widen the coverage area, and thus the number of served clients, several sector antennas are installed on the same supporting structure, e.g. tower or mast.

Spread spectrum makes it possible to have as low a frequency reuse factor as 1, if each base station is divided into 3 cells by means of 3 directional sector antennas.

Slot antennas are widely used in radar antennas, for the sector antennas used for cell phone base stations, and are often found in standard desktop microwave sources used for research purposes.

Often sector antennae have sharp "nulls" in their vertical pattern, so changing the tilt angle of sector antennas with a spectrum analyzer connected to monitor the strength of the interference can place the offending device within the null of the sector.