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Motivations for LTE

Internet and Mobile have become the basic need for everyone now a days. If internet goes down around the globe for few Days or even for few hours, it will give a huge impact on IT market and people's life. We are addicted of it.

So the questions come is, How does internet reaches us?
Answer is: It comes using LAN, WAN, Wireless etc. LAN or WAN is wired network. The success story of LAN & WAN is that it can give you speed upto 1000 Mega bits/Sec (as per: 802.3z).
But what's about Wireless network?? Till now it can give upto 21 Megabits/Sec only (as per HSPA).
So, To increase the speed of wireless network, It is redesigned to Evolved the previous architecture. The committee formed by 3GPP came up with a new solution with the name of LTE (Long Term Evolution).

So, What was the expectations for LTE?
These are the minimum expectation from LTE
1. Dowlink speed should be 100 Mbps in 20Mhz Bandwidth with two antennas
2. Increased "cell edge bitrate". So, the better experience at cell edge users.
3. Significantly improve the spectral efficiency 3-4 times release 6 HSPDA in the downlink
4. Very less latency when starting device to connect with network as well as while signalling.
5. Scalable bandwidth. It may support : 1.4, 3, 5, 10, 20 MHz
6. Inter working with existing systems like 3G systems and non 3GPP-systems.
7. Cost effective porting from previous system.
8. Backward network compatibility.
9. Support for further enhancement.
10. Optimized for low moving mobile but efficient for high mobile speed.
11. Less complicated infrastructure
12. Co-existence with .operators in adjacent bands as well as cross-border co-existence.

So, these are the main points what 3GPP expects from LTE.

In the next post we'll see how much LTE can deliver.


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