Today there are very few areas that do not have surrounding cellular towers and infrastructure. With 95 percent of the population owning a cell phone, Americans have come to rely on their mobile devices and they expect to be connected wherever they are. While there are far fewer places without cell service than there were even five years ago, there are still some spaces where cell signal is impaired or non-existent.
To find out why, let’s first take a look at what enables strong cell signal and how it works. Cell phones communicate using radio waves, which transport digitized voice or data across an electromagnetic field (EMF). The rate of oscillation (how quickly the waves rise and fall) is known as frequency. Radio waves carry the information and travel in air at the speed of light.
Cell phone signal strength is received by a mobile phone from a cellular network. Signal is measured in decibel-milliwatts (dBm). Depending on your proximity to a cell tower, and any obstructions such as buildings or trees, signal strength will be stronger or weaker.
Contrary to popular belief, the bars on your cell phone have little to do with the actual strength of the cell signal you’re getting. The number of bars can vary based on cell carrier, phone manufacturer, or even the way you hold your phone. The bottom line is that there is no standard for what these bars mean or what they actually measure, be it data or voice performance across 3G, 4G, or 5G networks.
Rural or sparsely populated areas are more likely to have weak or no signal — aka, dead zones. Even in areas where there are cell towers nearby, there are a number of reasons signal can be blocked, including dense forests or vegetation, or certain types of terrain. Weather conditions can also play a role in impeding signal.
Although most urban areas are well supplied with strong cellular coverage, there can still be dead zones indoors as well. This is why calls are dropped or downloading and uploading data on your mobile device is impossible even when you’re inside of an office building, for example.
When it comes to indoor cell signal, however, most cell users expect to have coverage and when there is no coverage it can be frustrating. The reason for a lack of strong cell signal in a building has to do with the many building materials that prevent the signal from surrounding cell towers from reaching a phone or other mobile device, and vice versa. Materials such as brick, concrete and LEED-certified windows that are common in commercial and residential buildings, are notorious cell signal killers.
When you’re using your cell phone it transmits radio waves in all directions. But in many buildings, these waves can be absorbed and reflected by surrounding objects before they reach the nearest cell tower, therefore impeding strong signal before it reaches your phone or other mobile device.
Because a cell phone is a two-way wireless communication device, it requires both the inbound signal (reception) and the outbound signal (transmission) to work properly.
Even in areas that are well supplied by unimpeded cell signal, a high volume of traffic on the cellular network can also cause dropped calls or slow download/upload speeds. This is common in arenas, conference centers, or other large areas where many people are utilizing their mobile cellular devices at the same time.
So, what’s the solution? While remote, outdoor areas are more difficult to improve signal in, there are affordable solutions for improving cell signal indoors. Cellular signal boosters, or amplifiers, are an effective way to strengthen cell signal in areas where it is weak or non-existent. These boosters use a passive distributed antenna system, or passive DAS, to capture strong outdoor cell signal, bring it indoors, and amplify it by as much as 32 times.
Passive DAS is an effective solution because it can be installed exactly where better signal is needed and it isn’t invasive to existing structures because it doesn’t require fiber optic cable installation.