Directed wireless communications use directed antennas, and as a simple example of it is the mobile phone network, and the use of these antennas has many benefits, including:
Contributes to reducing the interference ratio in electromagnetic waves to interference between frequencies where there is a specific direction of the signal.
This means that the frequencies can be used multiple times in different places, without interference.
1-Steering contributes to loosening.
2- Wireless network
3-Unguided wireless communication
An unknown destination type of communication in which the receiver’s address has not been specified.
Wireless networks are a type of computer network that transmits information between nodes without the use of connecting wires.
This type of network is combined with remote control information transfer systems through the use of electromagnetic waves such as radio waves as the carrier of the information signal. The physical layer of the network.
Definition of wireless networks
Wireless Local Area Networks (WLAN) Now anyone can move anywhere he wants, even in public places, carrying a laptop or laptop computer, and without any wires, he can send or receive any e-mail and browse the Internet completely freely, and travelers can They become at the beginning.
From April 2004 on board a German Airlines plane, during transatlantic flights, the use of cell phones to connect to the Internet and all this thanks to the new technology, which is the wireless local area network (WLAN / Wireless Local Area Network).
This technology allows to communicate with the Internet via a radio signal (radio / RF). Instead of connecting with wires. Hotspots are places where anyone can use wireless technology to connect to the Internet. The number of hotspots reached hundreds of thousands around the world by 2005. Hotspot technology relies on two main components of communication:
Wireless computer card
1. Wireless computer cards, and they may be present in the mobile device or any other device, or they can be added to it. This card contains either an internal or an external antenna.
Wireless access point device
2. An access point that connects WLANs to the Internet. As for aircraft with hotspots, the access point problem is solved via an off-plane antenna linked to special satellites that connect to the network via ground receiving stations.
In terms of speed and cost, compared to other technologies, wireless local area network technology using radio signals (WLAN) has overcome the problem of transmitting information wirelessly over relatively long distances at a moderate cost. For example, it exceeded the technology of transmitting information via infrared as it was limited to distances of no more than 20 meters.
It is not able to break through barriers, and it also surpassed the Global System for Mobile Communications used in mobile phones, because the transmission of information in WLAN technology is much faster and at moderate costs, and because UMTS technology in a mobile phone is not present in sufficient quantities in the market today. This is a comparison of wired networks. Wired and wireless wireless networks are becoming widely used in companies and homes.
Determine the types of wireless networks
PANs (Personal Area Network): A personal wireless network is the network that connects devices in a relatively small area. Usually this space is within a domain where a person can access all of its parts. For example, Bluetooth technology, for example, connects a PC to headphones. Also, ZigBee technology supports applications of this type of network.
WLAN networks: Wireless local area network is the most common type of wireless network.
It delivers devices farther away than the previous type, such as a home, office, or even a building, and sometimes extends to cover several kilometers. Most LANs are based on the IEEE 802.11 standard, which contains standards for wireless LANs that operate in the 2.4, 3.6, and 5 GHz bands and include a number of different protocols.
The important characteristics of this network compared to a WAN are that it transmits data at much higher speeds, transmitting data at 10 to 10,000 Mbps. Current LANs – most of which are not wireless – are based on the Ethernet standard.
Wi-Fi, which is commonly used as an alternative to IEEE 802.11, although this use is scientifically incorrect. Because Wi-Fi is a company logo indicating that devices that follow the previous standard can communicate together.
Fixed wireless data: These are wireless networks that are used to achieve a connection between two devices or networks in two different locations. This is done using microwaves or lasers at the line of sight (line of sight).
This type of network is often used to connect networks in neighboring buildings without the need to physically connect these buildings together.
Mann Networks: An urban area network connects several LANs to each other to achieve a wireless network that spans a medium-sized geographic area, such as a campus or city. The service you perform is similar to the service provided by your Internet provider (ISP).
WiMAX is the term used to refer to this type of network and is covered by the IEEE 802.16d and IEEE 802.16e standards developed by the Society of Electrical and Electronics Engineers.
There are two advantages to this type of network
- The size of this type of network is larger than a LAN. Several MAN regions cover an area the size of a city, and some cover a cluster of buildings with a diameter of 5 to 50 km.
- MAN operates as a high speed network to allow local and regional resource sharing. It is often used to provide or support a subscription to connect to other networks using a WAN connection.
Uses of wireless networks
Wireless networks have played a major role in global communication since World War II. With wireless networks, information can be sent over long distances across seas in an easy, practical and reliable way. Since that time, wireless networks have evolved greatly and have many uses in a wide range of fields, including:
1-Cell phones are massive worldwide network systems that are increasingly being used to communicate between people from all over the world.
2-The transmission of large-scale information over vast distances is made possible by wireless networks through the use of communication satellites.
3-Urgent communications – such as police communicating with one another – have become much easier with wireless networks.
4-Individuals and businesses alike can use these networks to provide fast connection, whether it is near or long distances.
5-One of the most important benefits of wireless networks is that they are used as a cheap and fast way to connect to the Internet in areas where there is no infrastructure to provide 6-this connection well, as is the case in most developing countries.
Pros and cons of using wireless networks
Flexibility (wireless): Wireless networks have more benefits than wired networks, and one of these benefits is flexibility, as radio waves pass through walls and a wireless computer can be anywhere on the access point.
Ease of use: Wireless networks are easy to set up and use.
Only an assistant program and a laptop or desktop computer equipped with a wireless network card, and there are computers equipped with this card, such as Centrino devices.
Planning: Wired and wireless networks must be carefully planned, but the worst of wired networks is that they make the appearance of walls untidy and the multiplicity of devices is expensive to maintain. The components of wired networks are (cables, switches, HP, path … etc) so we have to plan them carefully. As for wireless networks, it is much easier than this logic, but we must plan these networks for actual usage patterns.
The location of the devices: the wireless network can be hidden, and it can be placed behind the screens, and these networks are well suited for places or locations where a wired network is difficult to connect to, such as old museum buildings.
Durability: Wireless networks can be durable, but they may suffer from wireless interference from other devices. Performance may suffer when users try to use the same access point.
Prices: The wireless network was very expensive. A PCI wireless card cost 100 euros in 2000, and at the end of 2004 it cost only 30 euros. This means that the prices are not that high now and wireless networks are becoming the option for many home users.
Despite these benefits, wireless networks are not without some problems, the most important of which are:
Compatibility issues: Devices made by different companies may not be able to communicate with each other or they may need additional effort to overcome these issues.
Wireless networks are often slower than directly connected networks using Ethernet technologies.
Wireless networks are weaker in terms of protecting privacy because anyone within the coverage of a wireless network can attempt to penetrate that network.
To solve this problem, there are several programs that protect wireless networks, such as Wired Equivalent Privact (WAP), which did not provide adequate protection for wireless networks, and Wi-Fi Protected Access (WPA), which showed more success in preventing intrusions than its predecessor.
Health concerns of wireless networks
Recently, concerns have increased about the risks of wireless networks and the electromagnetic fields they generate despite the lack of conclusive evidence to substantiate these claims. For example, the president of Lakehead University in Canada refused to establish a wireless network on campus due to a study saying that the effect of exposure to electromagnetic fields resulting from wireless networks on the incidence of cancers and tumors should be studied further before determining them. The extent of this effect.
Well-known brands that specialize in wireless networks
- Quick touch
- Buffalo (disambiguation)
- Net Gear