Cell Phone Tower Antenna Basics and Types

This article covers the basics of cell phone tower antennas and explores different types used in cellular networks. We’ll look at both omnidirectional and directional antennas, as well as common antenna mount types.

Figure 1: Cell tower with different antenna configurations

Figure 1 illustrates a cell tower with various antenna configurations. Antenna arrays are typically configured with either horizontal or vertical separation. For microwave links between cell towers, circular horn antennas are commonly used.

Antennas can be used for transmitting, receiving, or both (transmitting and receiving). When an antenna is used for both transmission and reception, a duplexer is employed to separate the signals.

To avoid interference, a minimum distance of 10 times the wavelength (10λ) is generally maintained between transmit or receive antennas. For example, at 900 MHz, this translates to a horizontal separation of approximately 3.3 meters and a vertical separation of approximately 5.7 meters.

Figure 2: Cell phone tower antenna types

Antenna Types: Omnidirectional vs. Directional

Antennas used on cell towers can be broadly classified into two main types based on their functionality:

• Omnidirectional Antennas: These antennas transmit and receive signals in all directions. A common example is the dipole antenna.

• Directional Antennas: These antennas transmit and receive signals in a specific, desired direction. Examples include circular and rectangular horn antennas.

Directional antennas are often created by arranging multiple antenna elements in an array. These arrays can be either parasitic arrays or driven arrays. The specific arrangements of these arrays are depicted in Figure 1.

Figure 3: Cell tower antenna mount types

Antenna Mount Types

Figure 3 illustrates various antenna mount types used during cell tower installation. The specific type of mount used depends on the antenna type, tower structure, and other factors.