Cellular 101: Understanding Wireless Phone Coverage

Wireless telephones work by communicating via radio waves using a system of base stations (sometimes known as “cell sites”) that send and receive calls and relay them to other networks, like the Public Switched Telephone Network (PSTN). Because wireless phones communicate using radio waves, their reliability is influenced by many factors, such as the proximity of the phone to the base station with which it is communicating, physical obstacles, and interference or noise. Noise refers to unwanted electronic signals introduced by circuit components or natural disturbances that tend to distort communications. For example, like other radio transmissions, wireless phone calls can be affected by severe weather, large buildings, or other objects between your phone and the nearest base station or antenna that your wireless service provider uses.

• Ask neighbors, colleagues, and friends. You can also visit Internet sites like Cellular Maps.com.
• Test the wireless service providers’ plan and coverage area on a trial basis, if possible. Some wireless providers offer trial periods, during which you can test a phone before you are committed to a service contract and have to pay a significant fee to terminate that contract. Be aware, however, that if you terminate during a trial period or at any other time, most wireless service providers will not refund any activation or usage fees. During the trial period, you may want to test the phone in the areas where you plan to use it most frequently to determine if the actual coverage suits your needs.
• Check out the wireless service providers‘ coverage map on its Web site and/or in stores where its products are sold. Often these maps show very general coverage for entire regions. The maps usually carry a disclaimer saying they are provided for informational purposes only and that actual coverage may vary. There may be holes where the service provider does not have cell sites or where the topography causes dead zones. With few exceptions, the maps do not indicate signal strength or dead zones. Additionally, these coverage maps are not intended to show whether coverage is provided in obstructed areas, like buildings, tunnels, and underground garages. While wireless service providers often deploy in-building wireless solutions for these areas, any lack of coverage is usually not disclosed.

There is no guarantee that your phone will work in an area, even if it is included on a wireless service providers’ published coverage map. Just because a wireless service provider generally advertises service to an area, there may be several reasons why the service is not reliably available in all locations. Although wireless service providers attempt to design their networks to eliminate dropped calls, busy signals, and dead zones, no network is perfect, so coverage breaks within the general coverage areas are still possible. Specific and/or updated information may not be available on maps provided by the wireless service provider, because coverage is frequently changing.


Roaming
“Roaming” is the term that describes a wireless phone’s ability to make and receive calls outside the home calling area under your service plan. Roaming occurs when a subscriber of one wireless service provider uses the facilities of a second provider. While the subscriber usually has no pre-existing agreement with the second provider to handle calls, the subscriber’s provider may have a “roaming agreement” with the second provider. Under that agreement, the second provider agrees to handle calls placed by subscribers of the first provider and vice versa. When your phone is roaming, an indicator light on your phone may display the word “roam.” On occasion, your handset will not display a roaming indicator, even though it is in a roaming area. Also, some handset software needs to be updated monthly. Often this can be done by simply pressing a few buttons on the handset. Keeping that software updated can increase reliability and reduce incorrect roaming charges.

Contact your provider for more information about roaming areas, related fees, and software requirements. If your handset signal or the service provider’s signal from the nearest antenna is too weak, roaming can occur automatically, even if you are using your phone in your own home calling area. A phone can also go into “roaming mode” if there is a high volume of calls in the area. For example, though you may be surrounded by sites from your provider, each of your provider’s sites may be at its capacity or out of range. Instead of having a call blocked or dropped, your phone might use another provider’s site (roam), sometimes at an additional cost to you. Roaming fees are typically charged on a per-minute basis and determined by your service provider.

Many wireless service providers have eliminated these fees in their nationwide pricing plans. All of the major wireless service providers and many others now offer pricing plans that allow consumers to purchase a “bucket” of monthly minutes to use nationwide without incurring roaming charges. You should be aware, however, that wireless service providers define “nationwide” in different ways. For example, some providers define “nationwide” as anywhere in the country, whereas others define it as anywhere within the provider’s network. Check with your wireless service provider for information on the availability of plans without roaming charges or other roaming options.


Emergency Situations
Some people purchase wireless phones for emergency use only. These people rely on their wireless phones as a vital means of getting help during personal and other emergencies. Remember that during widespread emergencies, the calling volume in particular geographic areas can increase significantly, and a wireless phone call may not go through. When call volume is high and capacity is limited, consider sending a text message. Text messages require much less capacity, so they may go through even if a voice call cannot. Often, a cellular phone can complete a call to 911 even though the phone's screen says "No Service."