Enterprise Solution Guide Lines

Large buildings are inherently prone to week cell phone signal by design, literally! Large buildings are designed to withstand large loads and anytime large loads are a concern, steel is the answer. Steel buildings can withstand large loads and are the fastest way to erect tall structures. Now with that kind of steel structures comes the real trouble when it comes to cell phone signal. Cell phone signals are strong enough to penetrate sheet rocks and some time brick walls, but not a candidate to go through steel structures. Steel is a trapper of cell phone signals and it is what the engineers call a Faraday’s cage

The above illustration shows how the magnitude of the strength of a cell phone signal drops to nothing when it comes to metal. The good news is that since metal is such a good trapper of cell phone signal, the signal that is once inside cannot get outside the box as well. The way we solve big steel structure, signal problems is by by passing the steel structure via cable.

As you can see in the image above, how the cell phone signal is captured outside the building, where the cell signal is stronger using our Yagi antennas that are able to harness all the signal that the cell phone tower emits by using its unique design and transferred to the cell phone amplifier inside the building.

Guide lines to pick the type of antenna and number of indoor antennas

a) Our large Force5 amplifiers can be a 1,2,3 or 4 antenna systems depending on the coverage needs and number of floors you want to boost signal for. Typically with 3 signal bars outside the building, each indoor antenna can cover 15,000 sq ft.

b) If you have 3+ bars outside the building always pick an omnidirectional antenna, in case you decide to expand in the future. The omnidirectional antenna allows you to add another outdoor antenna without interference.

c) When it comes to selecting the indoor antenna, choose dome antenna for square space that mounts on the ceiling.The dome antenna shoots signal in a 360 degree pattern to cover the maximum area.

d) Choose Panel antenna for rectangular buildings, since they broadcast signal facing forward and suited for longer rectangular space.

Cable Limitations

One of the biggest misnomer is that the external antenna has to be on the line of site to the cell phone tower it is receiving and broadcasting the signal. The external antenna both Omni-directional and Yagi antenna are multiple times sensitive then the regular cell phone antenna. If you receive a dropped call or a missed call at a given location means their is ample signal for the external antenna to work with and amplify it. Running a longer cable to have a clear line of sight dilutes the signal due to signal loss inherent in the cable. Every 100 ft of cable can loose up to a 6dB in signal strength. If that happens before the amplifier that is in the cable that runs between the external antenna and the amplifier which typically tend to be weaker due to your particular geographical location issues, then by the time the signal reaches the amplifier to get boosted it is already lost its strength. The amplifier amplifies the signal it is given, if the amplifier receives a weaker signal , then the amplification achieved is relatively weak compared to a signal that is stronger at the input to the same amplifier.

So the rule of thumb is to keep the cable length between the external antenna and amplifier as short as possible. If you absolutely need a longer cable for you particular building, then extend the cable length between the amplifier and the internal dome antenna in the diagram below, for illustration.


Separation
Why separation needs to be of certain distance?

This is the distance between the indoor antenna and the outdoor antenna. In the illustration above, the it is essentially the straight line distance between the external Yagi antenna and the internal dome antenna. Both the antennas the receive and broadcast FROM and TO the cell phone tower. If the antennas are in close proximity to each other then the antennas can mistake each other for a cell tower and start a endless feedback loop where the two antennas the indoor and outdoor antenna continuously communicate with each other without giving the user a chance to chime in on the action. That is why the separation is an important aspect when installing the 2 antennas.

How to solve separation problems?

It is very simple, separate them further ! Now, there can be further difficulties to that, because you might run out of cable to increase the distance, in that case make sure the external antenna is a Yagi antenna. A Yagi antenna is directional and simply by pointing the antenna away from the indoor antenna, one can get rid of this problem.