Wireless is a term used to define telecommunication and data transmission without wires.
In a broad sense, wireless refers to any telecommunications or data transfer in which electromagnetic waves -- rather than some form of wire or cable -- carry signals over all or part of the data communication path.
The first wireless transmitters went on the air in the early 20th century using radiotelegraphy, which is radio communication using Morse Code or other coded signals. Later, as modulation made it possible to transmit voices and music via wireless, the medium came to be known as "radio."
Modern wireless technology is largely concerned with data transmission. It enables all manner of data to be communicated over both short and long distances without the need for a physical wire.
What is a wireless network?
A wireless network is a grouping, or network, of multiple devices where data is sent and received over radio frequencies.
Wireless networks are different than wired networks, where one end of the data connection is physically connected by a cable to enable communication with the other end. Wireless networks remove the need for fixed wired data cabling within an organization or network to connect different endpoint computing devices -- such as tablets, laptops and smartphones -- and embedded and peripheral devices. Wireless backhaul is often part of large service provider networks, enabling the connection of the wireless network to a fixed network for transmission.
Wireless networks generally include some form of radio transmission for broadcasting and receiving wireless signals across a specified range of electromagnetic radiation spectrum, commonly referred to simply as "spectrum." Transmission of data across a wireless network is typically done via antennas, which are often small, embedded pieces of hardware within a given device. Different wireless networks will use various frequency ranges of spectrum. Within the spectrum, there are also different channels to help reduce the risk congestion within a given spectrum frequency.
Types of wireless networks
There are multiple types of wireless networks that serve different needs, including:
- Municipal wireless network (MWN). An MWN is a wireless network that a local government authority operates. It provides access to users across a given geography.
- Wireless local area network (WLAN). A WLAN is enabled via Wi-Fi technology in a local area network. It uses a wireless access point that enables connectivity with endpoint devices. WLANs also use multiple specifications of Wi-Fi standards, including Wi-Fi 6 -- also known as 802.11ax -- which is the latest generation and standard for wireless internet.
- Wireless metropolitan area network (WMAN). A WMAN provides access outside the office and home networks. It is larger than a wireless local area network, but smaller than a wireless wide area network.
- Wireless personal area network (WPAN). A WPAN is generally enabled with short-range wireless technology, such as Bluetooth, to connect with devices such as keyboards, mice and headphones.
- Wireless wide area network (WWAN). A WWAN is also sometimes referred to as mobile broadband. WWAN uses cellular technology -- including 2G, 3G, 4G, LTE and 5G -- to enable wireless communications.
Types of cellular networks
There are several types of cellular networks used to enable data and voice communications with smartphones. For much of the 1990s and 2000s, the following two primary types of cellular networks were used for mobile data and voice communications:
- Global system for mobile communications (GSM). In the U.S., AT&T and T-Mobile have operated on the GSM network.
- Code-division multiple access (CDMA). In the U.S., Sprint and Verizon have operated on the CDMA network.
GSM and CDMA each had their own access methodologies that applied to 2G and 3G cellular specifications. With the advent of 4G/LTE and 5G in the 2000s, carriers are retiring their older CDMA and GSM networks.
Modern cellular networks are typically defined in terms of which generation of wireless standards is supported.
- 2G. This first major wave of cellular technology adoption was introduced in 1991, with speeds limited to 50 Kbps.
- 3G. Third-generation networks began to appear in 2001. 3G offered increased bandwidth and signal quality over 2G and provided a peak speed of 7.2 Mbps.
- 4G/LTE. Fourth-generation wireless and long-term evolution (LTE) began to appear in 2009 as successors to 3G. As opposed to the prior 2G and 3G standards, the International Telecommunications Union (ITU) specified a strict minimum data rate for 4G. To be considered 4G/LTE, the cellular networks must be able to transmit and receive at 100 Mbps.
- 5G. Fifth-generation wireless was first introduced as a technical standard in 2016; carriers began deploying it in 2019. 5G provides more bandwidth than its predecessors, that can range as high as 20 Gbps.
What is the difference between Wi-Fi and wireless?
Wireless communication is any transmission that occurs without the use of a cable or wire. In contrast, Wi-Fi is a specific subset of wireless that is defined by a set of technical specifications outlined by IEEE (Institute of Electrical and Electronics Engineers) under the designation 802.11. There are multiple Wi-Fi standards, including 802.11a/b/c/g/n/ac/ax, with each providing different performance characteristics.
In recent years, at the behest of the Wi-Fi Alliance, rather than referring to Wi-Fi standards by their IEEE designations, the 802.11ac and 802.11ax specifications have been branded as Wi-Fi 5 and Wi-Fi 6 respectively.
Wi-Fi is typically enabled on WLANs, with the use of a wireless access point or a wireless router, which broadcasts a service set identifier beacon. An endpoint device or user with a Wi-Fi-enabled network interface can then choose to connect to a given access point to enable the Wi-Fi connection.
Examples of wireless equipment
An ever-expanding array of wireless equipment enables users to stay connected without being tethered by wires. Common examples of wireless equipment include the following:
- Cellular phones -- providing connectivity for portable and mobile applications, both personal and business.
- Cordless telephone sets -- limited-range devices within a home that include a base tethered to a wall with cordless handsets.
- Global positioning systems -- enabling car and truck drivers, boat and ship captains, and aircraft pilots to ascertain their location anywhere on earth.
- Cordless computer peripherals -- using devices such as cordless mice, keyboards and printers, which can be linked via wireless protocols including Wi-Fi and Bluetooth.
- Wireless LANs -- enabling users to be untethered to a line to access a network.
- Wireless routers -- enabling users to connect to the internet at home or in the office via Wi-Fi. Wireless routers typically include a wired connection that enables connectivity to the internet, with antennas that provide wireless connectivity for users.
- Laptops and tablets -- mobile computing devices including laptops and tablets are Wi-Fi-enabled, providing wireless connectivity.
- IR wireless -- using devices that convey data via IR (infrared) radiation; employed in certain limited-range communications and control systems.