Chapter 8:Introduction of 3G evolution

by: Saroj Dhakal

Third-generation mobile communication started in ITU (International Telecommunication Union) at1980s.

The evaluation criteria set the target data rates for the 3G circuit-switched and packet-switched data services:

• Up to 2 Mbps in an indoor environment.• Up to 144 kbps in a pedestrian environment.• Up to 64 kbps in a vehicular environment.

Driving forces for 3G EvolutionDiscussion started in December2004State of the art then:The combination of HSDPA and Enhanced

Dedicated Channel (E-DCH) provides very efficient packet data transmission capabilities ,but UMTS should continue to be evolved to meet the ever increasing demand of new applications and user expectations.

10 years have passed since the initiation of the 3G program and it is time to initiate a new program to evolve 3G which will lead to a 4G technology

Driving forces cont..The key drivers are:• staying competitive• services (better provisioning of old services

as well as provisioning of new services)• cost (more cost-efficient provisioning of old

services as well as cost-effective provisioning of new services)

Driving forces cont..From the application/user perspectives, the UMTS

evolution should target at significantly higher data rate and throughput, lower network latency, and support of always-on connectivity.

From the operator perspectives, an evolved UMTS will make business sense if it:

Provide significantly improved power and bandwidth efficiencies

Facilitate the convergence with other networks/technologies

Reduce transport network costLimit additional complexity

Driving forces cont..Technology advancements: The technology

advancement is necessary to provide new and more advanced services at a reasonable cost as well as to provide existing services in a better and more cost-efficient way.

Services: is very difficult to predict what services will be popular in a 5- to 10-year perspective.

Unfortunately, there are also technical limitations that need to be understood, and also the technical innovations that in the future enable new services.

Led to 3GPP Study Item (StudyPhase:2005-4Q2006) “3GLong-term Evolution(LTE)” for new Radio Access and “System Architecture Evolution” (SAE) for Evolved Network

Development Trends..

201120102009200820072006200520042003200220012000

R99 R4 R5 R6 R7 R8 R9 R10

UMTS

HSPA

DL

HSPA

UL

LTE

LTE

Adv

HSPA

+

EPC

Common

IMS

IMS

MMTel

IMS: IP Multimedia Subsystem (IMS) is an architectural framework for delivering Internet protocol (IP) multimedia services.MMTel: 3GPP /NGN IMS Multimedia Telephony Service (MMTel) is a global standard based on the IMS, offering converged, fixed and mobile real-time multimedia communication . A Common IMS, developed in one place, is a big step forward and will bring enormous economies of scale and reductions in capital and operational costs.The main component of the SAE architecture is the Evolved Packet Core (EPC), also known as SAE Core

3G evolution: Radio Access Network evolution: RAN organized a workshop on 3GPP long-term

Evolution in the fall of 2004. The workshop was the starting point of the development of the Long-Term Evolution (LTE) radio interface.

The LTE radio access should be based on OFDM in the downlink and single carrier FDMA in the uplink.

Essentially, the target with HSPA Evolution is to reach near the characteristics of LTE when using a 5MHz spectrum and at the same time being backward compatible.

3G evolution cont..Thus, 3GPP is working on two approaches for 3G

evolution: the LTE and the HSPA Evolution. Both approaches have their merits. LTE can operate in new and more complex

spectrum arrangements (although in the same spectrum bands as WCDMA and other 3G technologies) with the possibility for new designs that do not need to provide for terminals of earlier releases.

HSPA Evolution can leverage on the installed base of equipment in the 5MHz spectrum but needs to respect the backward compatibility of earlier terminals.

3G evolution cont..The 3GPP Long-Term Evolution is intended to

be a mobile-communication system that can take the telecom industry into the 2020s.

LTE do not need to be backward compatible with WCDMA and HSPA.

In the LTE case, the radio interface can be purely optimized for IP transmissions.

3G evolution cont..Operators get more and more scattered

spectrum, spread over different bands with different contiguous bandwidths.

LTE needs to be able to operate in all these bands and with the bandwidths that is available to the operator.

However, in practice only a limited set of bandwidths can be used since otherwise the RF and filter design would be too costly.

3G evolution cont..LTE is therefore targeted to operate in 1.25,

1.6, 2.5, 5, 10, 15, and 20Hz spectrum allocations.

The spectrum flexibility support with the possibility to operate in other bandwidths than 5MHz makes LTE very attractive for operators.

The low-bandwidth operations are suitable for reforming of spectrum (for example GSM spectrum and CDMA2000 spectrum).

3G evolution cont..The higher-bandwidth options are suitable for new

deployments in unused spectrum, where it is more common to have larger chunks of contiguous spectrum

Furthermore, when going to the data rates that LTE is targeting, achieving low delay and high data rates at the cell edges are more important requirements than the peak data rate.

Thus, a more pronounced requirement for LTE is the low delay with high data rates at the cell edges than it was when WCDMA was designed in the late 1990s.

3G evolution cont..An evolved core network: System Architecture

Evolution:The System Architecture Evolution study focused on

how the 3GPP core network will evolve into the core network of the next decades.

The existing core network was designed in the 1980s for GSM, extended during the 1990s’ for GPRS and WCDMA.

The philosophy of the SAE is to focus on the packet-switched domain, and migrate away from the circuit-switched domain. This is done through the coming 3GPP releases ending up with the Evolved Packet Core.

3G evolution cont..

Thank You……………………..