A signal booster has two types of antennas; external antenna and internal antenna. The external antenna receives the incoming cell signals and the internal antenna rebroadcasts the amplified cell signals. Both the antennas act as the anterior and posterior limbs of a signal booster. The external antenna will capture the existing outside cell signal and send it to the amplifier unit. The amplifier will increase the strength of the cell signal and the internal antenna will rebroadcast the amplified cell signal.
Let’s take a look at each type of antennas used in cellular repeaters.
There are mainly two types of external antennas for a signal booster system. They are omnidirectional antenna and unidirectional antenna. You need to choose the type of external antenna that is to be used in your house based on the availability of the cell signal, number of network carriers, and distance from the cell tower.
An omnidirectional antenna is the most common type of external antenna used in urban areas. This is because omnidirectional antennas can capture cell signals from all directions and usually has a cylindrical shape. In urban areas, there are many network carriers and you may not get proper cell reception due to the many high rising buildings that surround you.
If you use an omnidirectional antenna, you could capture cell signals of all the network carriers at once. Omnidirectional antennas are the ideal choice for in-vehicle signal boosters. However, these antennas have a disadvantage. The omnidirectional antenna does not give much gain to the signals coming from the cell tower.
The unidirectional antennas capture cell signals only from one direction. But they are much powerful than omnidirectional antennas. They are mainly used in urban areas where there are no cell towers nearby. To avoid call drops and slow data speeds, signal boosters have to capture cell signals from longer distances. It is the ideal choice for those who are living in very remote locations.
Yagi antenna and log-periodic antenna are the two types of unidirectional antennas available and the most common unidirectional antenna is the yagi antenna. It is almost three times powerful than the omnidirectional antenna. Yagi antennas can boost any type of cell signals, including 3G, 4G LTE, and 5G signals. Log-periodic antennas are thirty times more powerful than yagi antennas. They can easily capture cell signals from more than 10 miles.
The internal antenna is considered as the posterior limb of the signal booster. The main purpose of the interior antenna is to redistribute the amplified cell signals to all the nearby cellular devices. Panel antenna, dome antenna, and whip antenna are the three main types of internal antennas of the signal boosters. You can choose the type of internal antenna to use based on the internal structure of the building.
Panel antennas are the ideal choice for redistributing boosted cell signals across hallways and narrow rooms. They are usually used in small offices and multi-story apartments. The panel antenna has a 45-degree coverage and transmits the amplified signals in a beam pattern. This antenna provides a gain of 7 dB on the 698 to the 960 MHz bands and about 10 dB gain on the 1700-2700 MHz band. You can mount panel antenna on the walls or the ceilings of the room.
Dome antennas are mainly used for redistributing the boosted cell signals inside square-shaped rooms and single-story buildings. This antenna is usually installed on the ceiling. A dome antenna can redistribute amplified cell signals in all directions. There are two types of dome antennas; indoor standard dome antenna and the ultra-thin antenna. The indoor dome antenna will provide a gain of 2 dB on the 698-960 MHz band. On the other hand, the ultra-thin antenna offer a gain of 3.5 dB on the 698-960 MHz band.
For redistributing amplified cell signals in small spaces like the inside of a car, RV, truck, or a small room, a whip antenna is an ideal choice. Like the dome antenna, the whip antenna can also redistribute boosted cell signals in all directions. On the 698-960 MHz band, a whip antenna will offer a gain of 2 dB and on the 1700-2700 MHz band, whip antennas will provide a gain of 5 dB.
Antenna separation is one of the important aspects that you should remember while installing the external and internal antennas of a signal booster system. When you install the external and internal antennas, you need to keep enough distance between the antennas. This is for preventing the antennas from picking up each other’s signals.
When the external and internal antennas of the signal booster are close to each other, it will create a feedback loop, which will affect the performance of the signal booster and may damage the cellular network. Therefore, you need to ensure that there is enough vertical and horizontal distance between both external and internal antennas of the signal booster.