LTE Introduction

Beyond 3G.
As we have seen in previous series of wireless telecommunication topics; After GSM(Global System for mobile communication)(2G) , HSPA is a 3G evolution of GSM supporting high-speed data transmissions using WCDMA technology.

In order to meet the continued traffic growth demands, an extensive effort has been underway in the 3G Partnership Project (3GPP) to develop a new standard for the evolution of GSM/HSPA technology towards a packet-optimized system referred to as Long-Term Evolution (LTE).

Goal:
The goal of the LTE standard is to create specifications for a new radio-access technology geared to higher data rates, low latency and greater spectral efficiency. The spectral efficiency target for the LTE system is three to four times higher than the current HSPA system.

In parallel, new network architecture is designed with the goal to support packet-switched traffic with seamless mobility, quality of service and minimal latency.


LTE Introduction
While HSPA (High Speed Packet Access) and HRPD(High Rate Packet Data) systems were being developed and deployed, IEEE 802 LMSC (LAN/MAN Standard Committee) introduced the IEEE 802.16e standard for mobile broadband wireless access. The 802.16e standard employed a different access technology named OFDMA (orthogonal frequency division multiple access) and claimed better data rates and spectral efficiency than that provided by industry group named by WiMAX. (Mobile WiMAX also employed a similar network architecture based on IP Protocols.

The Introduction to Mobile WiMAX led both 3GPP and 3GPP2 to develop their own version of beyond 3G system based on OFDMA(Orthogonal Frequency Multiple Access) technology and network architecture similar to that in Mobile WiMAX. The beyond 3G system in 3GPP is called evolved universal terrestrial radio access (evolved UTRA) and is also widely referred to as LTE (Long-Term Evolution) while 3GPP2’s version is called UMB (ultra mobile broadband).
All three beyond 3G systems namely Mobile WiMAX, LTE and UMB meet IMT-2000 requirements and hence they are also part of IMT-2000 family of standards.

Now Stay tuned for Air Interface, Protocols, and Network Architecture for LTE. :)

reference:
1) Wikipedia,
2) couple of web search and blogs.
3) F. Khan, "LTE for 4G Mobile Broadband - Air Interface Technologies and Performance", Cambridge University Press, 2009