There are a number of reasons why a cell phone call might drop, which can be categorized by problems with the carrier, problems in your local environment, and finally problems specifically with your phone. Let's examine each in more depth.
A cellular network is composed of many different cellular towers that your phone communicates with in order to make a phone call. Your phone automatically connects to the nearest tower when you're making a call and continues to communicate with that tower as long as it remains the closest one in range. If you're on the move though, whether walking, driving, or other, then you'll likely move out of the range of your closest tower and a handoff will occur to move your call to the new closest tower. Most of the time this handoff will occur without a problem, but occasionally there will be a complication and your call will be dropped during the handoff. That complication could be due to extreme cell traffic on either one of the towers, glitches in the backend software, power outages, and more. These are all problems on the side of the carrier, and while an inconvenience, you're usually able to make your call again without problem.
Another common reason for dropped calls is when you encounter an area with no reception, known as a "dead zone". Dead zones exist for a few different reasons. In remote areas, there are wide swaths of dead zone where there is no coverage available from cell towers because there are very few inhabitants or travelers. Desert areas are a great example of an environment where you'll find a large number of dead zones. In more populated areas, dead zones can still exist due to improperly aligned towers, which result in areas not receiving proper coverage, as well as in locations which are obstructed by obstacles like hills, mountains, trees, large buildings, etc. Finally, dead zones are frequently found underground, such as in subway lines, basements, and parking garages.
Apart from dead zones, your local environment can have an effect on dropped calls too. The main cause of bad reception in your local area is most likely the type of construction materials used in your home or office. Materials like wire mesh, sheet metal, types of insulation, reinforced concrete, and more all contribute to signal degradation and loss. If a digital cell phone signal becomes too degraded and enough data is lost in transit, then there is a high likelihood that the connection will be terminated and the call dropped, even if your phone shows that it still has a bar of signal.
Finally, your cell phone itself can be the cause for dropped calls. If your cell phone has a damaged antenna, you may experience poor cell phone reception, data loss and frequent dropped calls. Dropped calls and other problems can also occur if your phone's roaming software has not been updated recently or if it has been corrupted in any way. Finally, a cell phone requires a quality power supply to maintain a stable connection during a call, so if your battery is running out, the likelihood of a dropped call is also increased.
Overall, there are a number of factors related to location that are out of your hands which affect dropped calls, but there are also some that are within your power to change. In the next section, we'll cover how to solve the problems that you have control over to decrease the number of dropped calls that you experience.
