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Main article: "cellular network
Example of frequency reuse factor or pattern 1/4

A cellular network or mobile network is a radio network distributed over land areas called cells, each served by at least one fixed-location "transceiver, known as a "cell site or "base station. In a cellular network, each cell characteristically uses a different set of radio frequencies from all their immediate neighbouring cells to avoid any interference.

When joined together these cells provide radio coverage over a wide geographic area. This enables a large number of portable transceivers (e.g., mobile phones, "pagers, etc.) to communicate with each other and with fixed transceivers and telephones anywhere in the network, via base stations, even if some of the transceivers are moving through more than one cell during transmission.

Although originally intended for cell phones, with the development of "smartphones, "cellular telephone networks routinely carry data in addition to telephone conversations:

Global area network[edit]

A "global area network (GAN) is a network used for supporting mobile across an arbitrary number of wireless LANs, satellite coverage areas, etc. The key challenge in mobile communications is handing off user communications from one local coverage area to the next. In IEEE Project 802, this involves a succession of terrestrial "wireless LANs.[10]

Space network[edit]

Space networks are networks used for communication between spacecraft, usually in the vicinity of the Earth. The example of this is NASA's "Space Network.

Different uses[edit]

Some examples of usage include cellular phones which are part of everyday wireless networks, allowing easy personal communications. Another example, Intercontinental network systems, use radio "satellites to communicate across the world. "Emergency services such as the police utilize wireless networks to communicate effectively as well. Individuals and businesses use wireless networks to send and share data rapidly, whether it be in a small office building or across the world.



In a general sense, wireless networks offer a vast variety of uses by both business and home users.[11]

"Now, the industry accepts a handful of different wireless technologies. Each wireless technology is defined by a standard that describes unique functions at both the Physical and the Data Link layers of the "OSI model. These standards differ in their specified signaling methods, geographic ranges, and frequency usages, among other things. Such differences can make certain technologies better suited to home networks and others better suited to network larger organizations."[11]


Each standard varies in geographical range, thus making one standard more ideal than the next depending on what it is one is trying to accomplish with a wireless network.[11] The performance of wireless networks satisfies a variety of applications such as voice and video. The use of this technology also gives room for expansions, such as from "2G to "3G and, most recently, "4G technology, which stands for the fourth generation of cell phone mobile communications standards. As wireless networking has become commonplace, sophistication increases through configuration of network hardware and software, and greater capacity to send and receive larger amounts of data, faster, is achieved.[12]


Space is another characteristic of wireless networking. Wireless networks offer many advantages when it comes to difficult-to-wire areas trying to communicate such as across a street or river, a warehouse on the other side of the premises or buildings that are physically separated but operate as one.[12] Wireless networks allow for users to designate a certain space which the network will be able to communicate with other devices through that network.

Space is also created in homes as a result of eliminating clutters of wiring.[13] This technology allows for an alternative to installing physical network mediums such as "TPs, "coaxes, or "fiber-optics, which can also be expensive.


For homeowners, wireless technology is an effective option compared to "Ethernet for sharing printers, scanners, and high-speed Internet connections. WLANs help save the cost of installation of cable mediums, save time from physical installation, and also creates mobility for devices connected to the network.[13] Wireless networks are simple and require as few as one single "wireless access point connected directly to the Internet via a "router.[11]

Wireless Network Elements[edit]

The telecommunication network at the physical layer also consists of many interconnected wireline "network elements (NEs). These NEs can be stand-alone systems or products that are either supplied by a single manufacturer or are assembled by the service provider (user) or system integrator with parts from several different manufacturers.

Wireless NEs are the products and devices used by a wireless carrier to provide support for the "backhaul network as well as a "mobile switching center (MSC).

Reliable wireless service depends on the network elements at the physical layer to be protected against all operational environments and applications (see GR-3171, Generic Requirements for Network Elements Used in Wireless Networks – Physical Layer Criteria).[14]

What are especially important are the NEs that are located on the cell tower to the "base station (BS) cabinet. The attachment hardware and the positioning of the antenna and associated closures and cables are required to have adequate strength, robustness, corrosion resistance, and resistance against wind, storms, icing, and other weather conditions. Requirements for individual components, such as hardware, cables, connectors, and closures, shall take into consideration the structure to which they are attached.



Compared to wired systems, wireless networks are frequently subject to "electromagnetic interference. This can be caused by other networks or other types of equipment that generate radio waves that are within, or close, to the radio bands used for communication. Interference can degrade the signal or cause the system to fail.[4]

Absorption and reflection[edit]

Some materials cause "absorption of electromagnetic waves, preventing it from reaching the receiver, in other cases, particularly with metallic or conductive materials reflection occurs. This can cause dead zones where no reception is available. Aluminium foiled thermal isolation in modern homes can easily reduce indoor mobile signals by 10 dB frequently leading to complaints about the bad reception of long-distance rural cell signals.

Multipath fading[edit]

In "multipath fading two or more different routes taken by the signal, due to reflections, can cause the signal to cancel out at certain locations, and to be stronger in other places ("upfade).

Hidden node problem[edit]

The "hidden node problem occurs in some types of network when a "node is visible from a "wireless access point (AP), but not from other nodes communicating with that AP. This leads to difficulties in "media access control.

Shared resource problem[edit]

The wireless spectrum is a limited resource and shared by all nodes in the range of its transmitters. "Bandwidth allocation becomes complex with multiple participating users. Often users are not aware that advertised numbers (e.g., for "IEEE 802.11 equipment or "LTE networks) are not their capacity, but shared with all other users and thus the individual user rate is far lower. With increasing demand, the "capacity crunch is more and more likely to happen. "User-in-the-loop (UIL) may be an alternative solution to ever upgrading to newer technologies for "over-provisioning.



Channel capacity in wireless communications
Understanding of SISO, SIMO, MISO and "MIMO. Using multiple antennas and transmitting in different frequency channels can reduce fading, and can greatly increase the system capacity.

"Shannon's theorem can describe the maximum data rate of any single wireless link, which relates to the bandwidth in hertz and to the noise on the channel.

One can greatly increase channel capacity by using "MIMO techniques, where multiple aerials or multiple frequencies can exploit multiple paths to the receiver to achieve much higher throughput – by a factor of the product of the frequency and aerial diversity at each end.

Under Linux, the Central Regulatory Domain Agent (CRDA) controls the setting of channels.[15]


The total network bandwidth depends on how dispersive the medium is (more dispersive medium generally has better total bandwidth because it minimises interference), how many frequencies are available, how noisy those frequencies are, how many aerials are used and whether a directional antenna is in use, whether nodes employ power control and so on.

Cellular wireless networks generally have good capacity, due to their use of directional aerials, and their ability to reuse radio channels in non-adjacent cells. Additionally, cells can be made very small using low power transmitters this is used in cities to give network capacity that scales linearly with population density.[4]


Wireless electronic devices and health

Wireless access points are also often close to humans, but the drop off in power over distance is fast, following the "inverse-square law.[16] The position of the "United Kingdom's "Health Protection Agency (HPA) is that “ frequency (RF) exposures from WiFi are likely to be lower than those from mobile phones.” It also saw “ reason why schools and others should not use WiFi equipment.”[17] In October 2007, the HPA launched a new “systematic” study into the effects of WiFi networks on behalf of the UK government, in order to calm fears that had appeared in the media in a recent period up to that time".[18] Dr Michael Clark, of the HPA, says published research on mobile phones and "masts does not add up to an indictment of WiFi.[19]

See also[edit]


  1. ^ "A New Clustering Algorithm for Wireless Sensor Networks" (PDF). 
  2. ^ "Overview of Wireless Communications". Retrieved 8 February 2008. 
  3. ^ "Getting to Know Wireless Networks and Technology". Retrieved 8 February 2008. 
  4. ^ a b c "Guowang Miao, Jens Zander, Ki Won Sung, and Ben Slimane, Fundamentals of Mobile Data Networks, Cambridge University Press, "ISBN 1107143217, 2016.
  5. ^ "Wireless Networks: Bluetooth To Mobile Phones". 
  6. ^ "Wireless Network Industry Report". Retrieved 8 July 2008. 
  7. ^ "Wi-Fi Personal Area Networks get a boost with Windows 7 and Intel My WiFi". Retrieved 27 April 2010. 
  8. ^ "Facts About WiMAX And Why Is It "The Future of Wireless Broadband"". 
  9. ^ "GSM World statistics". GSM Association. 2010. Retrieved 16 March 2011. 
  10. ^ "Mobile Broadband Wireless connections (MBWA)". Retrieved 12 November 2011. 
  11. ^ a b c d Dean Tamara (2010). Network+ Guide to Networks (5th ed.). Boston: Cengage Learning. "ISBN "978-1-4239-0245-4. 
  12. ^ a b "Wireless LAN Technologies". Source Daddy website. Retrieved 29 August 2011. 
  13. ^ a b "WLAN Benefits". Wireless Center commercial web site. Retrieved 29 August 2011. 
  14. ^ GR-3171-CORE,Generic Requirements for Network Elements Used in Wireless Networks – Physical Layer Criteria
  15. ^ Anadiotis, Angelos-Christos; et al. (2010). "Towards Maximising Wireless Testbed Utilization Using Spectrum Slicing". In Thomas Magedanz; Athanasius Gavras; Huu Thanh Nguyen; Jeffrey S. Chase. Testbeds and Research Infrastructures, Development of Networks and Communities: 6th International ICST Conference, TridentCom 2010, Berlin, Germany, May 18–20, 2010, Revised Selected Papers. 6th International ICST Conference, TridentCom 2010, Berlin, Germany, May 18–20, 2010. 46. Springer Science & Business Media. p. 302. Retrieved 2015-07-19. […] Central Regulatory Domain Agent (CRDA) […] controls the channels to be set on the system, based on the regulations of each country. 
  16. ^ Foster, Kenneth R (March 2007). "Radiofrequency exposure from wireless LANs utilizing Wi-Fi technology". Health Physics. 92 (3): 280–289. "doi:10.1097/01.HP.0000248117.74843.34. "PMID 17293700. 
  17. ^ "WiFi". "Health Protection Agency. 26 October 2009. Retrieved 27 December 2009. 
  18. ^ "Health Protection Agency announces further research into use of WiFi". "Health Protection Agency. Retrieved 28 August 2008. 
  19. ^ Daniels, Nicki (11 December 2006). "Wi-fi: should we be worried?". The Times. London. Retrieved 16 September 2007. All the expert reviews done here and abroad indicate that there is unlikely to be a health risk from wireless networks. … When we have conducted measurements in schools, typical exposures from WiFi are around 20 millionths of the international guideline levels of exposure to radiation. As a comparison, a child on a mobile phone receives up to 50 percent of guideline levels. So a year sitting in a classroom near a wireless network is roughly equivalent to 20 minutes on a mobile. If WiFi should be taken out of schools, then the mobile phone network should be shut down, too—and FM radio and TV, as the strength of their signals is similar to that from WiFi in classrooms.... 

Further reading[edit]

External links[edit]

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