Cell Phone Dead Zones: How Do Dead Zones Occur and What Can We do About Them?

based on 3 ratings
Author: Melissa Bautista

Physical Science, Engineering



Difficulty of the Project




Safety Issues


Approximate Time Required to Complete the Project
5-7 days


This project will examine the reasons for various dead zones.

Materials and Equipment/Ingredients

  • Cellular Phone


Have you ever talked on the phone while riding the subway, the bus, or driving through a tunnel and suddenly the call ends? You have most likely hit a dead zone. With the increase in cell phone usage over the past decade it is hard to imagine an area without cell phone reception. However, even in the most populated cities, such as New York City, dead zones occur, and often. These zones vary from carrier to carrier or depending on your cellular phone. Finding the cause of these dead zones can help cellular phone companies improve cell phone reception and coverage to their customers. This is important in the event of an emergency. If you're in an area without cell phone reception you will be unable to dial 911 during an emergency. In this study we will examine various dead zones and investigate the cause and how it can be fixed.

Terms, Concepts and Questions for Background Research

  • How do cell phones work?
    • Radio Frequency
    • Full duplex, Half-duplex
    • Channels
    • Range
    • Bandwidth
    • Transmitters & transmission signals
    • Networks
    • Interference
    • Digital encoding
  • Causes of interference
    • Network overlaps
    • Topography
    • Other transmission signals - satellites

Research Questions

  • Where are the dead zones?
  • Where are towers located?
  • What other factors contribute to the interference?
  • How can we eliminate the dead zone? Would putting in more towers solve the problem?

Experimental Procedure

  1. Find the dead zones. You may already know of a few. You can also find them on (Figure 1).

Figure 1. Map showing the areas that experience dead zones. Colors represent the various carriers. Taken from 

  1. Assess the area. You should go to the area without reception. Use your cell phone to confirm loss of signal/service.
    1. What is the terrain like? In a valley? Highly wooded? Concrete Jungle?
    2. What services are interrupted? Sprint? Verizon? AT&T? All?
  2. Map the area. Using you can locate the area from Google maps (Figure 2). The map will show you the location of the cell phone towers.
    1. Which companies have towers in the area?
    2. Using your background research estimate the transmission radius. Any overlaps?

Figure 2. Map showing cellular phone tower distribution. Taken from 

  1. Find sources of interruptions. Using Google Maps (Figure 3) you can search for radio stations, television stations, etc. near the dead zone area.

Figure 3. Map showing the locations of various radio stations and broadcasting companies from a Google maps search. 

  1. Record your information using a map. This can be digital or using a paper map. Google maps allows you to use markers to create your own map.


Add your own comment