How Wireless Works

A wireless phone is a very sophisticated and versatile radio. Similar to a walkie-talkie, a cellphone receives and sends radio waves. Those radio waves, traveling through spectrum, are used to transmit voice calls and data to your mobile device anywhere, anytime. Mobile products and services are also used to improve efficiencies and effectiveness in a variety of other industries such as health care, education, transportation and energy.

How wireless works - areas divided into cells

Areas are divided into cells of a few blocks up to hundreds of square miles, depending on expected traffic.
How Wireless Works - Each cell has base stations

Each cell has base stations with wireless antennas to transmit signals.
How Wireless Works - cell antennas

Cell antennas can be hidden in numerous ways and can be as small as conventional speakers.
How Wireless Works - Wireless Networks
Wireless networks automatically transmit your call to the antenna with the strongest channel.
How Wireless Works - Wireless Calls
Wireless calls then go from a base station to the landline network to the person you're calling.
How Wireless Works - Today's wireless device
Today's wireless devices give you the power of a personal computer in the palm of your hand.

What's Inside
Today’s wireless devices are actually miniature computers. Inside your wireless phone, there is a compact speaker, a microphone, a keyboard, a display screen and a powerful circuit board with microprocessors. When connected to a wireless network, this bundle of technologies allows you to make phone calls, access the Internet, engage in social networking and exchange data with other phones and computers around the world. The components operate so efficiently that a lightweight battery can power your phone for days.

The Nuts and Bolts
Wireless networks operate on a grid that divides cities or regions into smaller cells. One cell might cover a few city blocks or up to 250 square miles, depending on the amount of network traffic a carrier anticipates in a given area. Every cell uses a set of radio frequencies or channels to provide service in its specific area. The power of these radios is controlled in order to deliver capacity and service quality, meet federal safety standards and to limit the signal’s geographic range, which means the same frequencies can be reused in nearby cells. This lets many people talk simultaneously in different cells throughout the city or region, even though they are sharing the same channel.

The number of users in a given area matters. The more people wanting to use their wireless devices, the more capacity is needed to provide service. That’s why more antennas are necessary in densely populated areas than in less populated rural settings.

Also, remember that wireless devices are radios and are ruled by the laws of physics. Trees, tall buildings, hilly terrain or bad weather can affect interference levels. Some dead spots also exist because cells vary in size and there might be slight gaps in coverage areas. Improving coverage requires adding antennas or relocating existing ones.

Connecting to the Wireless Network
When you turn on your wireless phone, it searches for a signal from the closest antenna. It quickly transmits a unique identification data so your service provider knows it’s your device and where it is so you can be served.

Wireless calls are usually transmitted over a landline network. If you’re calling another wireless user, the call will eventually go back through a wireless antenna to the recipient’s wireless device.

So what makes this “mobile”? Wireless base stations are “smart” and can sense when your signal can be stronger as you move toward a closer antenna.

That’s how your call stays connected while you’re on the move. Wireless base stations keep track of you, and hand over your signal connection as you move from one cell to another served by another base station. Using smaller cells, which means more towers or base stations, also enables your device to use less power and maintain the signal connection as you move.

If you travel outside your home area and make a call, another wireless carrier might provide service for your wireless phone. That provider sends a signal back to your home network, so you can send and receive calls as you travel. This is called roaming. Roaming is key to mobile communications, as wireless providers cooperate to provide callers service wherever they go, including travel from one country to another.

Since the shape and size of cells vary, there might also be empty spaces between the coverage areas of two or more cells. These gaps or dead spots can also be caused by trees, tall buildings or other obstructions that block your wireless signal from reaching a nearby antenna. Wireless service providers work hard to provide extensive coverage. Since the laws of physics govern wireless signals, some dead spots exist because a local government or landowner won’t allow placement of a wireless antenna in a specific area or if the signals are disrupted by the topography of an area.

Mobile Goes Digital
Today wireless phones use digital technology, which converts your voice and information into the binary digits 0 and 1 – much like a music CD. The binary digits are aggregated into small packets of data that are relayed through wireless networks to the receiving device or websites and servers connected to the Internet. On the receiving end, the conversion process is reversed and the person you are calling hears your voice, reads your email or texts or sees your multimedia message. Again, all of this happens incredibly quickly because of the sophisticated technology built into the devices and networks.

Americans Need Speed
As wireless data demand grows and expands, the wireless industry continues to leverage  advanced packet-based networks using the same technology as the Internet. Today, wireless networks operate at data speeds five to ten times greater than earlier wireless networks. 4G, or LTE next generation networks support even greater transmission speeds and high-bandwidth, capacity demanding applications such as streaming HD video and advanced capabilities such as Voice-over-Internet Protocol (VoIP).

These faster, higher bandwidth and more efficient networks mean that we are able to manage our professional and personal lives in amazing new ways. From social networking, to real-time GPS navigation and maps, mobile payments, video streaming and un-tethered access to the Internet, there’s a lot of information available at our fingertips anywhere, anytime.

Last Updated: November 2013
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