What is the most common type of radio transmission used in wireless networks?
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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. Show
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 networksThere are multiple types of wireless networks that serve different needs, including:
Types of cellular networksThere 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:
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.
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 equipmentAn ever-expanding array of wireless equipment enables users to stay connected without being tethered by wires. Common examples of wireless equipment include the following:
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