Cellular Communication Network Technologies
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Cellular communication is a form of communication technology that enables the use of mobile phones. A mobile phone is a bidirectional radio that enables simultaneous transmission and reception. Cellular communication is based on the geographic division of the communication coverage area into cells, and within cells. Each cell is allocated a given number of frequencies (or channels) that allow a large number of subscribers to conduct conversations simultaneously. |
Illustration of communication coverage
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The common element of all generations of cellular communication technologies is the use of defined radiofrequencies (RF), as well as frequency reuse. This enables the provision of a service to a large number of subscribers while reducing the number of channels (band width). It also enables the creation of wide communication networks by fully integrating the advanced capabilities of the mobile phone. The increase in demand and consumption, as well as the development of different types of services, accelerated the rapid technological development of advanced cellular communication networks, together with unceasing improvement of the cellular devices themselves.
Most common types of communication technology
- Global Systems for Mobile (GSM) Communications
- Code Division Multiple Access (CDMA)
- Universal Mobile Telecommunication System (UMTS)
- Long Term Evolution (LTE) using the Orthogonal Frequency Division Multiplexing (OFDM)method
- Adaptive communication
Global System for Mobile (GSM) Communications
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SIM card |
GSM communication technology is based on the GSM standard – the first to use the cellular protocol that replaced the earlier first-generation communication standard. This standard was developed by the European Communications Standards Institute (ETSI), starting from 1982, for the second generation (2G) of digital cellular communication. This standard, defined as digital, was based on optimal switching of a communication network to full duplex speaking telephony, and was subsequently expanded to include data packet transfer communication. From 1989 the GSM standard was enhanced to become an international standard, and it covered up to 90% of the activity of the second-generation phones in 219 countries and territories. In fact, GSM technology replaced the restrictive analog communication, and was a technological turning point, which was followed by the development of innovative cellular communication technologies. The second generation of GSM thus constituted the foundation for subsequent generations of cellular communication. In Israel a GSM cellular system was set up in 1999 by "Partner", operating under the trade name of "Orange". In 2001 "Cellcom" joined the providers of GSM in Israel, after installing a GSM network parallel to the time division multiple access (TDMA) network it operated previously. In 2009 "Pelephone" also began using GSM technology. |
Code Division Multiple Access (CDMA) technology
CDMA technology was originally developed for the US Army during the Vietnam War, as a way of disguising conversations intended for military purposes. This method separates different conversations by coding rather than by time sharing (as in the EDMA/GSM technologies) or by frequency sharing (FDMA) as with the NAMPS technology. The method of separation by coding enables conducting a large number of conversations simultaneously over the same range of frequencies, with no interference between them.
"Qualcomm", which developed this technology, applied it to cellular communications that use coded speech at different rhythms – a technology whereby the cellular device receives simultaneous information from a number of base stations. This technology ensures the continuity of conversations during movement from one cell to another.
For further details on this CDMA technology
Universal Mobile Telecommunication Systems (UMTS) technology
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UTMS technology, based on Wideband Code Division Multiple Access (W-CDMA) technology, is one of the third-generation (3G) technologies of mobile phone telephony. This technology was designed by the Third Generation Partnership Project (3GPP), a collaboration between groups of telecommunications associations to create a globally applicable third-generation mobile phone system, and represents the European-Japanese counterpart to the International Mobile Telecommunications for the year 2000 (IMT-2000) International Telecommunications Union (ITU) specifications for cellular communication systems. In order to differentiate between UMTS and other communication network technologies, it is sometimes marketed under the label GSM3 – a name that emphasizes its place in the third generation, and the fact that it replaced the GSM in the second generation system. |
third-generation (3G) |
For further details on W-CDMA and UMTS.
Long Term Evolution (LTE) technology, operating according to the method of Orthogonal Frequency Division Multiplexing (OFDM)
LTE is not only an additional generation in the evolution of cellular technology, but rather one that is being developed while considering the future requirements of wireless data communication and the scientific and technological developments in this field. This is due to its ability to transmit data at a rate of hundreds of megabytes per second, up to a gigabyte per second, at low cost. The rise of LTE today and in the near future may resemble the revolution caused by the introduction of mobile phone technology in the 1980s, and even the appearance of Wi-Fi. Just as the move from analog to digital communication with the appearance of 2G devices caused a tremendous revolution, so the move from 3G to LTE is also causing a revolution. LTE technology operates through the method of orthogonal frequency division multiplexing (OFDM) which is the main characteristic of fourth-generation (4G) technology.
Unlike the modulation methods of second-generation technology such as time division multiplexing (TDM), and unlike the use of code division multiplexing (CDM) in third-generation GSM, the OFDM method provides optimal solutions for the common problems encountered in wireless communication arising from multiple reflections and dispersions of radio waves in a channel, and movement of the transmitter or receiver. In Israel this technology is being introduced gradually because it requires redeployment of the cellular networks.
For further details on this LTE and LTE-Advanced technologies.
Adaptive communication
An innovative feature of CDMA technology and other new communication technologies is the close monitoring of power which enables adaptive communication. This feature allows the cellular device to vary its power dynamically at any given time. This means that a cellular communication network using this technology and others may conduct dynamic communications adapted to the conditions of reception and the quality of communication. In other words, the device's power changes in response to factors such as distance, angle of direction or presence or absence of obstructions, thus enabling efficient communication while restricting the power optimally and decreasing the level of radiation exposure.
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Illustration of Cellular communication
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Illustration of smart phone communications telephony in a city
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References
- Muthu Chidambara Nathan P. Wireless Communications [Kindle Edition], PHI Learning Private Limited. 2013.
- Cox C. An Introduction to LTE: LTE, LTE-Advanced, SAE, VoLTE and 4G Mobile Communications. 2nd Edition. 2014; Wiley.
- Communication Technology Update and Fundamentals, 14th edition (Grant AE, Meadows JH, editors, in association with Technology Futures, Inc.). Focal Press, New York and London. 2014.
- Jones S, Kovac RJ, Groom FM. Introduction to communications technologies: a guide for non-engineers. 2nd Edition. 2008; CRC Press.
