0G or pre-cellular network is here just for the sake of reference, always remember your ‘roots’ kind of thing. They operated mostly the same way as the landlines did the only difference was they were wireless. Some people would still wish for these types of networks for two reasons. One, it may be a good choice for long range communication in scarcely populated areas (a single tower, Base Station, can cover an area of 40-60 miles). Two, you could listen to them using your Radio
Technology: IMTS (Improved Mobile Telephone Service).
When? 1960’s
Frequencies: VHF Low (35–44 MHz), VHF High (152–158 MHz), UHF (454–460 MHz).
Facilities/Benefits: Simultaneous two-way communication (full duplex) and Direct Dialing, no waiting for the operator.
Availability: scarce, discontinued.
Limitation/s: very limited number of subscribers could be added.
1G Network:
Again an analog communication system, almost same as the previous 0G network. It can also be a good choice for long range communication. The technology used here (AMPS) was later converted to D-AMPS (Digital-AMPS) which is a 2G standard.
Technology: AMPS (Advanced Mobile Phone Service)
When? 1980’s. first installation 1982.
Frequencies: 800Mhz
Facilities/Benefits: Could accommodate 5 to 10 times more users than IMTS by dividing an area into smaller cells (hence the tern ‘cellular network’).
Availability: Effectively discontinued & replaced by digital networks.
Limitation/s: Severe security issues. Not even you could listen into the conversation but could hack it for free calls (make someone else pay the bill).
2G Networks:
From here after the term ‘technologies’ will be replaced by ‘standards’. For you understanding you can just ignore this and keep on reading it as technologies.
Standards: GSM & CDMAOne.
When? GSM: 1990, Finland. CDMA: 1989, San Diego US. (A reason why GSM is widespread in Europe and adjoining countries while CDMA has a large penetration in US.)
Frequency: GSM: 850/900, 1800/1900Mhz. CDMA: 450 MHz for CDMA450.
Facilities/Benefits: Digital Communication, High security (encrypted calls, GSM was just recently hacked in 2010), Short Message Service (SMS), Effective use of bandwidth compared to previous generations.
Limitation/s: Digital communication is affected by weather conditions very severely than analog communication. Range is limited compared to 1G. Data rate (speed/Kbps) is too slow for modern era’s needs.
Availability: GSM: an estimated 4,927,613,300 (4.927 billion)
Extended 2G Standards: GPRS,EDGE, CDMA1xRTT.
3G Networks:
These standards were improved significantly and thus the newly emerging ones were named Third Generation or 3G.
So if a company is using GSM as it’s 2G backbone to move to 3G it will have to use an improved form of the GSM standards and if a company was on CDMA (e.g. VPTCL) it will use an improved form of the CDMA standards for their network to be called 3G complaint.
Also, any mobile telecommunication service that fulfills the requirements of the ITU (International Telecommunication Union) can be classified as a 3G network/service.
Standards: UMTS (loosely based on GSM/EDGE), CDMA2000 (evolutionary upgrade to CDMAOne).
When? Around 2000 for CDMA2000 & 2002 for UMTS (official launch years by carriers).
Frequency: UMTS: (varies by carrier/region) 850/1900,1700,2100Mhz. CDMA2000: varies by operator/region.
Facilities/Benefits: Improved data rates allowing high speed downloads and desktop like web-browsing. 21Mbps for HSDPA (improved version of UMTS) and upto 14.1Mbps for EVDO Rev. B (a member of the CDMA2000 family).
Limitation/s: Actual download speeds can be less for power downloader.
Availability: Lot’s of countries around the world have moved to 3G even in our neighborhood India and Sri Lanka have UMTS/HSDPA deployed.
Extended 3G Standards: HSPA/HSPA+, EVDO Rev. A, EVDO Rev. B.
4G Networks:
For 4G technologies I will limit myself to LTE (Long Term Evolution) as it is going to be the replacement for both the UMTS and CDMA2000 based technologies in the future.
Technologies: LTE (loosely based on UMTS).
When? TeliaSonera 2009 & Verizon Wireless 2010.
Frequency: 700Mhz
Facilities/Benefits: 100mbps download speed & 50mbps upload. Also, it improves the efficiency of the network and reduces congestion (less dropped calls). At least 200 active users in each 5Mhz Cell (remember cell from cellular network?)
Limitation/s: Upgrade of infrastructure will be required.
Availability: Deployed in selected regions, more specifically selected cities.
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