In computing and telecommunications, a type of connection between computer systems (that is, between computers ) that is carried out employing various waves of the electromagnetic spectrum is known as a wireless network.
In other words, it is a node connection that does not require any type of wiring or wired device, since the transmission and reception of information occur through specialized ports. This type of technology represents a huge leap forward from traditional methods
It originated in 1971, when a group of researchers led by the American computer engineer Norman Abramson (1932), created at the University of Hawaii ALOHA, the first packet switching system through a radio wave communications network.
ALOHA was made up of 7 computers located on different islands in the region linked together through a central server that performed different calculations to supply them. The first drawback was that the messages from the different stations did not overlap each other, which required the creation of the first MAC protocols.
The following year, ALOHA was already connecting to ARPANET, the American computerized information service, the forerunner of the Internet.
Types Of Wireless Networks
Wireless networks can be classified based on two different criteria:
According to its area of reach. They are classified similarly to wired networks:
- WPAN. Acronym for Wireless Personal Area Network has a maximum range of 10 meters, so it can be used for one or two users maximum, who are together. These types of technologies include Bluetooth, ZigBee, etc.
- WLAN. Acronym for Wireless Local Area Network is the communications standard on which WiFi technologies are based, capable of reaching a much greater distance based on repeaters, interconnecting various types of devices using radio waves.
- WMAN. Acronym for Wireless Metropolitan Area Network, networks of much greater range, capable of covering up to 20 kilometers.
- WWAN. Acronym for Wireless Wide Area Network uses a cell phone and microwave technologies to transfer data over vast distances. Some of its types of technology are GPRS, EDGE, GSM, 3G, 4G, or 5G.
According to its frequency range. Depending on what part of the electromagnetic spectrum you use to transmit, we can distinguish between:
- Terrestrial microwave. Using parabolic antennas of about 3 meters in diameter, a microwave signal is emitted that has a range of several kilometers, using frequencies between 1 and 300 GHz.
- Satellite microwave. It operates based on the link between two or more base stations, through the intermediation of a satellite suspended in the atmosphere. Each satellite has its specific frequency bands, but it has a much greater range and a higher speed.
- Infrared. It uses modulators of non-coherent infrared light, which, when directly aligned or reflected on a suitable surface, reach between 300 GHz and 384 THz of data transmission speed. However, it cannot pass through walls.
- Radio waves. It uses waves at various frequencies (AM, FM, HF, VHF, UHF, etc.) to emit and receive information signals, achieving high efficiency over short distances, even through walls, but losing itself as the receiver moves. physically away from the sender.
Advantages Of Wireless Networks
The advantages of wireless networks can be summarized as:
- Savings in materials. Since kilometers of wiring and ground controllers are not required for the exchange of information.
- More agile communication. Since an artifact that is in motion, or remote places can be connected to the network.
- The multiplicity of connections. Since more than one device can be attached to the same wireless signal simultaneously.
Disadvantages Of Wireless Networks
On the other hand, wireless networks have the following difficulties:
- They require greater security. Since the signal is uncontrollable and free, and anyone can pick it up.
- They are susceptible to interference. Either from other signals on the same broadcast channel or continuous low-frequency noise, antennas, microwave devices, or even certain types of metals.
- Transmission is more complex. Since it requires additional mechanisms and devices to direct the transmission, and receiver devices with adequate power to achieve a stable and continuous signal.
Devices On A Wireless Network
Any wireless network must have the following elements:
- Wireless-capable devices. To connect to a wireless network, you will need a computer, telephone, tablet, or device equipped with an antenna capable of perceiving and emitting electromagnetic waves, that is, capable of receiving and emitting radio frequency signals. To do this, they must have a working wireless network card.
- Base stations. They are those modulators that convert the wired or traditional signal into a wireless signal transmitted by radio waves.
- Repeaters. Apparatus designed to capture and re-emit a specific electromagnetic wave signal, to give it a boost and allow it to go further or to places otherwise inaccessible.
- Routers and access points. Routers (“ routers ”) are devices that “translate” the Internet signal and direct it to access points so that it can then be distributed by these to the various users of a network. In addition, the former assigns an IP address, to control and organize access to data packets and avoid losses and overlaps.
Examples Of Wireless Networks
Some everyday examples of wireless networks include mobile phone networks, WiFi stations in our homes, in squares or at airports, or even satellite transmission via microwave or cable television that we consume in our homes.
The Bluetooth system with which we connect our wireless headphones to the music player or cell phone is also a good example.