Distance Between Outdoor Antenna and Indoor Antenna Myth!

What we are discussing here is something even professional installers have some questions about, and its time we discussed it to make the antenna installation simple. When a customer gets a repeater system from us , it comprises of three main components.

a) The outdoor antenna that seeks and sends out signal to the cell tower

b) The amplifier that amplifies the cell phone signal that goes TO and FROM the cell tower. What this means is that the amplifier not only amplifies the signal you receive, but also amplifies the signal you send out when making calls.

c) The indoor antenna takes the amplified signal from the amplifier and broadcast it within the building

Now when you install a system like this, the installation manual talks about how the two antennas (outdoor antenna and indoor antenna) has to be separated by a specific distance in order to get proper results. Now, lets understand the reason behind this requirement , so we can do proper installs. The antennas are basically a miniature version of the cell tower you have out in your vicinity and as far as they are concerned its like one cell tower talking to another. The cell towers prefer to talk to the its closest neighbor first, meaning that the two antennas you install are closer to each other then the cell tower and if not separated by a specific distance then they tend to talk to each other more often then communicating with the cell tower (our preferred outcome to boost the cell phone signal)

The antennas are not as powerful as the cell tower in your neighborhood, towering giant of 100 ft -200 ft or more. As a good rule of thumb the separation between antennas is pretty easy to determine, basically move the antenna as far as possible. The amplifier units will let you know if the antennas are too close by signaling a “Red” light instead of a “Green” light. Another good rule to follow is to base the separation depending upon the db gain of the amplifier as follows:

a) 45 dB gain amplifier, separation of 15 – 20 feet
b) 55 dB gain amplifier, separation of 20 – 30 feet
c) 62 dB gain amplifier, separation of 30 – 40 feet
c) 65 dB gain amplifier, separation of 30 – 40 feet
d) 75 dB gain amplifier, separation of 35 – 45 feet
e) 80 dB gain amplifier, separation of 45 – 50 feet

Note : If the building you are installing the booster systems happens to be a metal building or a metal roof, then the separation needed is provided by the building itself, since metal is a good barrier for cell phone signals.

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