It’s an everyday annoyance: you go from having perfectly functional reception, chatting away on a nice walk, only to find your call losing audio quality or even dropping entirely once you go indoors. Why does this happen?
There are many possible factors that can make it difficult to get a signal inside a specific space, like a house, office, or storefront. These factors can generally be categorized into three areas of focus, distance from the cell tower, exterior obstructions, and interior obstructions.
Distance from the cell tower is the easiest to understand of the three. Cell towers are structures that mobile service providers use to connect you to their mobile network. Whenever you call or text someone, you’re sending signals from your phone to one of your service provider’s cell towers, and whenever you receive a text or listen to someone on the other end of the call, your phone received the signals that make that possible from a cell tower. The problem is, as you travel further and further from the cell tower the signals both to and from the tower become weaker and weaker, fading over the distance. If the building you find yourself losing signal in is far away from areas with high cell coverage, then this might be contributing to your signal loss. Even if it’s not the main cause itself, a signal weakened by distance is more likely to be drowned out by obstructions than one that is close to its tower.
The next factor to consider is the presence of exterior obstructions. Exterior obstructions in this case are anything between you and the cell tower that might cause disruption in your signal. There are many things that can count as exterior obstructions under this definition, such as mountains, trees, and even other buildings. By creating a solid obstacle that cell signals must travel through, these exterior features further weaken the signal between you and the tower. That a whole mountain between you and your cell tower might weaken your connection may not come as a surprise, but did you know that even the weather can have an impact on the strength of your cellular connection? Clouds, especially lower and heavier clouds, can serve as obstructions, too. Thunderclouds in particular are known to cause trouble for cellular signals, since they tend to be the lowest and heaviest of typical weather patterns.
Finally, there are interior obstructions, or obstructions arising from the building itself. Interior obstructions can be split into two sub-categories, material obstructions and structural obstructions.
Material obstructions include any sort of building material that can create difficulties for cellular signals passing through them. This comprises nearly all modern, conventional, and historic building materials. Be it brick, concrete, or metal, most of what composes the structure of any building is going to make it harder for a cellular signal to pass through. Old or new, it doesn’t make a difference, something in there is going to be a thick-enough material for cell signals to have a hard time penetrating. In fact, many modern buildings pose their own unique issues because they utilize LEED-certified materials.
LEED, short for Leadership in Energy and Environmental Design, is a certification used to prove that a building has been made in a sustainable and environmentally conscious way. Many federal agencies, as well as both state and local governments either require it for certain cases or will reward developers for building according to LEED standards. With some of these rewards including tax credits, reduced fees, and expedited permitting that could all help give a business a leg up, it’s no surprise that many would want the potential boost to their bottom line and design their buildings accordingly even when not required to do so.
LEED encourages the use of energy-efficient materials, or special building materials that trap energy within a structure while not allowing more in. In essence, this allows a building to not have to rely on air conditioning or heating as much by simply keeping the inside of the building at a more consistent internal temperature. The problem with this and cellular signals is that much like heat, cell signals are a form of radiation. These energy efficient materials will indeed keep the warmth of the sun from heating things up, but they will just as easily prevent cell signals from coming and going. Because of this, getting signal within a LEED-certified building can be rather difficult, and a significant issue given around 60% of LEED-certified buildings are office buildings or related to the medical or educational fields, all areas where reliable cellular reception is in heavy demand.
Then there are structural obstructions. These don’t tend to come to mind for most people, but they are just as capable of weakening a cell signal as any other category we’ve explored so far. Structural obstructions are any way a building is structured that causes cellular signals to have difficulty propagating through. The classic example of a structural obstruction is interior walls. If the cell tower you’re connected to is on the other side of a building from you and you have many interior walls between you and the tower, your cellular reception will be worse than if there was nothing between you and the other side of the building but open air. Another structural obstruction, and one that is rarely thought of, is furnishings. Many forms of furniture use metal, which, as we established earlier in the section on building materials, does weaken cellular signals which pass through it. This means having large amounts of metal furniture between you and your cell tower could cause disruptions in your cellular service as well. Before you laugh off such a fate as one reserved for unfortunate furniture store employees, take a moment to consider the amount of metal desks contained within your average office building. Now consider the number of interior walls and the building materials likely used to make the building as a whole.
When you experience signal loss as you enter a building, it’s likely due to these factors all interconnecting. Chances are you aren’t close to a cell tower. You might not be extremely far away, but it’s certainly not next to the building you’re in if you’re losing connection to it. There are likely exterior obstructions in the signal’s path, probably other buildings, but, if you’re in a more mountainous or wooded area, then more natural obstacles could be in play as well. And finally, it’s near-guaranteed that the material and structure of the building you are standing in are working against you, especially if you’re having trouble with signal in an office building, hospital, or school, which are more likely to have been built with LEED-certified materials.
If you’re really unlucky, it might be all of this and a thunderstorm too.
