Cellular Technology Nut-Shell
Cellular technology is called cellular because of its mechanism. Cellular system uses many base stations to divide a service area into multiple cells. Using a cellular device a user can communicate while traveling from one area to another.The cell of a mobile phone functions as sender and accepter. A cell accepts & transfer small packets of data through a built in antenna device to specific location with some frequency. This specific location is called channel.
All mobile operators use radio spectrum in order to provider their services. Spectrum is a limited resource. Earlier, mobile operator companies used division of frequencies to enhance the capacity. However cellular technology allowed division of geographical areas (alternate of frequency) which is leading towards wide area coverage.
Cellular network is a combination of clusters. A cluster is a group of seven cells. Each cell has a base station in centre of it. Base stations provide control on sending/receiving. All base stations are connected to MSO (Mobile Switching Office) which is a central point. MSO is connected to PSTN (Public Switched Telephone Network.).
PSTN continuously monitors the quality of communications and call another PSTN.
Cellular devices are consists of mobile phones, handheld computers, portable mobile data devices, personal digital assistants etc.
Cellular technology is used for personal, commercial & military purposes. Different bands of radio spectrum are being used. Most popular bands are GSM-900 & GSM-1800. Most devices support multiple bands and work in any country. Some mobile operators are providing "extended GSM" a band for larger frequency range.
Types of Cellular Technologies:
Cellular technology systems use one of two ways
*Analog
*Digital
Access Types:
There are three types used to access the network.
*CDMA (Code Division Multiple Access)
*FDMA (Frequency Division Multiple Access)
*TDMA (Time Division Multiple Access)
IBM - CDPD
To examine the traffic voice & data users in a particular service area IBM has introduced a technology called Cellular Digital Packet Data (CDPD). It is based on transmission control protocol/internet protocol (TCP/IP).
CDPD overlays packet switching onto the existing cellular voice network, and transmits data packets over the idle capacity. CDPD does not need the call setup procedures required for switched voice calls. It resolved the problem of excessive data traffic & increases the network utilization.
History of Cellular Technology
1921:
United States police used a radio system in vehicles at 2Mhz Frequency.
1926:
Radio telephonic system was used in trains traveling between Berlin & Hamburg.
1940:
Motorola developed a radio mobile "Walkie-Talkie".
1941:
Motorola developed a mobile system for US military using 30MHz-40MHz frequencies.
1947:
In December 1947, Douglas H. Ring & Rae Young of Bells Labs made hexagonal cells for mobile phones.
1949:
Federal Communications Commission authorized separate radio channels to common carrier entities known as "Radio Common Carriers" (ROC).
1956:
The first fully automatic mobile phone system, called MTA (Mobile Telephone system), was developed by Ericsson and commercially released in Sweden.
1960:
Electronics technology developed by Bell Lab Scientists Richard H. Frenkiel & Joel S. Engel, it was first considerable step towards the era of cellular technology.
1964:
150MHz automatic channel selection system was introduced. This enables the customers to dial their own number.
1969:
IMTS (Improved Mobile Telephone System) launched in U.S. It was 450MHz.
1970:
Amos E. Joel of Bell labs invented "handoff" technology for cell phones.
1973:
On the streets of New York City using Motorola DynaTAC, Dr. Martin Cooper is the first in history who initiated a telephonic conversation. Call was made to Joel Engel researcher of Bell Labs on April 3, 1973.
1978:
Advanced Mobile Phone Service (AMPS) was used by Bell Labs to launch the first trial for commercial cellular network in Chicago.
1979:
NET in Tokyo Japan launched first recognized commercial cellular telecoms.
1981:
NMT system was launched in Denmark, Finland, Norway and Sweden.
1983:
Motorola Dyna 8000x received approval as the first handheld mobile phone in US.
1990:
Analog AMPS was surpassed by Digital AMPS.
Basics of Cellular Technology
Cellular technology also called wireless or mobile technology was in its early ages in 1960s. This technology is the world"s most popular thing since last five decades. Cellular concept has grown faster than anything else in this world.
Cellular technology is swiftly removing the wired technology fiber optics. According to a report of April 2000 from Tokyo:
"The number of mobile phone subscribers in Japan at the end of March exceeded fixed-phone subscriptions for the first time as the popularity of mobile communications continued to expand, according to Ministry of Posts and Telecommunications."
The reason is extensively rapid progress of cellular technology. Not only in mobiles but it is also being used in following fields.
*Health Care
*Energy
*Finance
*Defense
*Business
*Industry
*Research GSM is the most popular among cellular technologies like CDMS, TDMA, MMDS, LMDS, PCS, Blue Tooth and IEEE 802.11.
ITU is the department in USA for coordination. However in all countries government department take care of the major spectrums. Following topics are most important in regards to basics related to cellular technology.
*Radio Basics
*Frequency Bands
*Signals Processing
*Access Spectrum
*Modulation
*Range
*Interference In our further sections we will mainly focus on cellular networks & related terms. We have chosen a unique pattern of random explanation of definitions. This will be really helpful for those who are searching for any single term to understand. Unfortunately this website is not providing a proper solution of step-by-step learning. We express regret for visitors looking for such environment.
Intermediate Leve of Cellular Technology
Intermediate level of cellular technology starts from deploying mobile IP in wireless architecture. Mainly following topics are considered as more important in this level of study.
*Multi-path fading channel model
*Detection of non-encoded transmitting at narrow band fading channel
*Interleaving of coded symbols
*Orthogonal frequency division multiplexing (OFDM)
*Multiple Accesses
*Inter-cell interference management
*Space-time coding
*Power control & interference averaging
*Signal to interface and noise ratio (SINR)
*AWGN channel
*Multiple input output communication system (MIMO)
*Fourth generation (4G) wireless system
Advance Level of Cellular Technology
The past decade has been very action-packed in terms of cellular technology advancements. If sky would not be the limit then is has already been crossed by large enterprises like Nokia. Manufacturing of devices and service provision sector remain always in struggle for the next step. Yet being realistic we can say mathematics can never be changed. Basics of advance level rely on the very basic rules and fundamentals of cellular technology. Considering the topics advance level of cellular technology we have following topics.
*Successive interference cancellation (SIC)
*V-Blast architect
*D-Blast
*Space division multiple access (SDMA)
*SWOT Analysis of Cellular Technology Strengths:
*Wide coverage
*Small unit
*Low cost
*Ability to integrate
*High functionality
Weaknesses:
*Electromagnetic Rediation
*Loss of money
Opportunities:
*Jobs & Careers
*Business expansion
*Immediate support
*Fasten connectivity
Threats:
*Abnormal Human Generation Next
*No privacy Future of Cellular Technology
It"s Year 2009 now. It"s the right time to analyze the future of cellular technology.
Worldwide cellular phone subscribers are 4 billion now.
15-35 percent jobs are related to cellular technology.
Penetration rate (percentage of new subscribers of cellular technology) is 60% for year 2008.
Pakistan, India & China has approached very positively towards cellular use & turned Asia-Pacific into largest cellular market of the world.
Man has used mobile in space.
Pleasing factor for future of cellular technology is women"s participation in all sectors including manufacturing, development & research.
Mobile phones with 8 mega pixels camera are available in third world local markets.
Pre-4G technology is available.
Standards, coverage areas, bandwidth, costs, equipment models, network, everything is changing. Rapidly growing number of users indicates that it is technology feasible to connect to the world to the benefits of cellular system.