With the advent of generations after generation of mobile networks it has become important to understand the concept behind each. The evolution of the three generations has been explained in one of my previous blog. Please refer my previous article on how the 1g, 2g and 3g evolved.
In this article the focus would be more on understanding the subtle differences between the four generations. Let us start with the first two wireless generations first.
Analysis of 1g & 2g:
- In 1G, narrow band analogue mobile network is used.
- This facilitates the voice calls and sending text messages.
- These services are provided with circuit switching.
- Today the usual call starts from the beginning pulse to rate to the final rate. Then in case of 2G Narrow Band Wireless Digital Network is used. It brings more clarity to the conversation and both these circuit-switching model.
- Both the 1G and 2G deals with voice calls and has to utilize the maximum bandwidth as well as a limited till sending messages i.e. SMS.
- The latest technologies such as GPRS, is not available in these generations.
- But the greatest disadvantage as concerned to 1G is that with this we could contact with in the premises of that particular nation, where as in case of 2G the roaming facility a semi-global facility is available.
- 1G networks (NMT, C-Nets, AMPS, TACS) are considered to be the first analog cellular systems, which started early 1980s. There were radio telephone systems even before that.
- 2G networks (GSM, CDMA, DAMPS) are the first digital cellular systems launched early 1990s.
Some of the advantages that 2G had over 1G are:
- The lower powered radio signals require less battery power, so phones last much longer between charges, and batteries can be smaller.
- The digital voice encoding allowed digital error checking which could increase sound quality by increasing dynamic range and lowering the noise floor.
- The lower power emissions helped address health concerns.
- Going all-digital allowed for the introduction of digital data services, such as SMS and email.
- Greatly reduced fraud. With analog systems it was possible to have two or more “cloned” handsets that had the same phone number.
- Enhanced privacy. A key digital advantage not often mentioned is that digital cellular calls are much harder to eavesdrop on by use of radio scanners. While the security algorithms used have proved not to be as secure as initially advertised, 2G phones are immensely more private than 1G phones, which have no protection against eavesdropping.
The intermediate generation:
In between 2G and 3G there is another generation called 2.5G. The intermediate mobile generation if we can call it that.
Firstly, this mid generation was introduced mainly for involving latest bandwidth technology in addition to the existing 2G generation. But this had not brought out any new evolution and so had not became critical enough to be recognized as a standalone generation.
Arrival of 3G:
To overcome the shortcomings of 2G and 2.5G, the 3G had been introduced. In 3G Wide Brand Wireless Network is used with which the clarity increases and gives the perfection similar to that of a real conversation. The data are sent through the technology called Packet Switching .Voice calls are interpreted through Circuit Switching.
What is Packet Switching?
This is actually done by supplying various addressed packets, which will be interconnected to have the conversation. It is not necessary to create a new dedicated path for sending the data. It had been modified in such a way that the data can be send through any path and hence this data will be received in less time as compared to that of voice calls.
Main features of 3G Wireless Network:
The features and services of 3G are as follows:
- With the help of 3G, we can access many new services like global roaming.
- 3G also have Wide Band Voice Channel, by this the world has been contracted to a little village because a person can contact with other person located in any part of the world and can even send messages too.
- Then the point to be noted is that 3G gives clarity of voice as well can talk with out any disturbance.
- In addition to that 3G also have entertainments such as Fast Communication, Internet, Mobile T.V, Video Conferencing, Video Calls, Multi Media Messaging Service (MMS), 3D gaming, Multi-Gaming etc are also available with 3G phones.
- 3G networks (UMTS FDD and TDD, CDMA2000 1x EVDO, CDMA2000 3x, TD-SCDMA, Arib WCDMA, EDGE, IMT-2000 DECT) are the latest cellular networks that have data rates 384 KB/s and more.
- The bandwidth and location information available to 3G devices gives rise to applications not previously available to mobile phone users. Some of the applications are:
- Mobile TV – a provider redirects a TV channel directly to the subscriber’s phone where it can be watched.
- Video on demand – a provider sends a movie to the subscriber’s phone.
- Video conferencing – subscribers can see as well as talk to each other.
- Tele-medicine – a medical provider monitors or provides advice to the potentially isolated subscriber.
- Location-based services – a provider sends localized weather or traffic conditions to the phone, or the phone allows the subscriber to find nearby businesses or friends.
Main aspects of 4G Networks:
The Forth Generation could be ready for implementation around 2012.
- Then with the case of Fourth Generation that is 4G in addition to that of the services of 3G have some additional features such as Multi-Media Newspapers,
- You can also watch T.V programs with the clarity that of an ordinary T.V.
- In addition, we can send Data much faster that that of the previous generations
- A 4G cellular system must have target peak data rates of up to approximately 100 Mbit/s for high mobility such as mobile access and up to approximately 1 Gbit/s for low mobility such as nomadic/local wireless access, according to the ITU requirements.
- Scalable bandwidths up to at least 40 MHz should be provided.
- A 4G system is expected to provide a comprehensive and secure all-IP based solution where facilities such as IP telephony, ultra-broadband Internet access, gaming services and HDTV streamed multimedia may be provided to users.
- Although legacy systems are in place to adopt existing users, the infrastructure for 4G will be only packet-based (all-IP).
- Some proposals suggest having an open Internet platform. Technologies considered to be early 4G include: Flash-OFDM, the 802.16e mobile version of WiMax (also known as WiBro in South Korea), and HC-SDMA.
Indian market still awaits the full implementation of 3G and there are lot of issues relating to its availability. When 4G comes along it will also be seen whether it succeeds in the Indian context or not.