This document summarizes the evolution of cellular network technologies from 1G to 4G. It discusses the key standards, bandwidth capabilities, services provided and implementation timelines for each generation. It also provides details on the functional architecture and protocol stack of the 4G LTE network, including components like the eNodeB, EPC, and air interface technologies OFDMA and SC-FDMA. Finally, it gives a brief overview of WiMAX technology and its components like the ASN, ASN-GW and CSN.

1. Ms.J.Shiny Christobel
Assistant Professor
Department of ECE
Sri Ramakrishna Institute of Technology, Coimbatore

2. Technology 1G 2G 2.5G 3G 4G
First design 1970 1980 1985 1990 2000
Implementation 1982 1991 1999 2002 2010
Service Analog
voice
Digital voice,
SMS
Packaged
data
Broadband
data up to 2
mb/s
IP-oriented
unlimited
multimedia
data
Standards AMPS TDMA,
CDMA, GSM
GPRS, EDGE EV-DO,
W-CDMA,
HSDPA
WiMAX,
LTE
Data bandwidth 1.9 kbps 14.4 kbps 384 kbps 2 mbps 200 mbps

3. Functional changes compared to the current UMTS architecture

5. The User Equipment (UE)
UE – Mobile equipment
USIM :
1.This is also known as the SIM card for LTE equipments
2.Stores user-specific data very similar to 3G SIM card.
1.user's phone number,
2.home network identity and
3.security keys etc.

7. E-UTRAN Node B (eNodeB)
 Each eNB is a base station that controls the mobiles in one or more
cells.
 The base station that is communicating with a mobile is known as
its serving eNB.
 The eBN sends and receives radio transmissions to all the mobiles
using the analogue and digital signal processing functions of the
LTE air interface.
 The eNB controls the low-level operation of all its mobiles, by
sending them signalling messages such as handover commands.
 eBN connects with the EPC by - S1 interface
eBN connects with nearby base stations - X2 interface
(mainly used for signalling and packet forwarding during
handover)

9. The Home Subscriber Server (HSS)
-central database that contains information
about all the network operator's subscribers.
The serving gateway (S-GW)
- acts as a router, and forwards data between
the base station and the PDN gateway.
Packet Data Network (PDN) Gateway (P-GW)
-communicates with the outside world ie.
packet data networks PDN, using SGi interface.
The mobility management entity (MME)
controls the high-level operation of the
mobile by means of signalling messages

11. USER PLANE - data packets that are processed by protocols
CONTROL PLANE - signalling messages that are exchanged between the
base station and the mobile

12. The user plane protocol stack consists of the following sub-layers:
 PDCP (Packet Data Convergence Protocol)
 RLC (radio Link Control)
 Medium Access Control (MAC).
Packets received by a layer - Service Data Unit (SDU)
Packet output of a layer - Protocol Data Unit (PDU)

13. The control plane includes additionally the Radio Resource Control
layer (RRC) which is responsible for configuring the lower layers.
The grey region of the stack indicates the access stratum (AS)
protocols

14. OFDM – DOWNLINK
SC-FDMA – UPLINK
Why SC-FDMA for UPLINK???
1.large dynamic range required for OFDM
2.High PAPR
3.to achieve high efficiency in low power

15. OFDM
 OFDM divides the bandwidth into multiple
frequency sub-carriers.
 In OFDM sub-carriers are orthogonal to each
other.
 OFDM also uses multiple sub-carriers but the sub-
carriers are closely spaced to each other without
causing interference, usingguard bands between
adjacent sub-carriers.

16. How does a SC-FDMA signal look like?
Similar to OFDM signal, but…
-in OFDMA, each sub-carrier only carries information related to one specific
symbol
-in SC-FDMA, each sub-carrier contains information of ALL transmitted
symbols.

17. WI-MAX

18. WHY WIMAX?????
 Wi-Fi signals can not cover more than a
hundred meters.
 Both LOS and NLOS support.
 Higher data rate than former
technologies.
 WIMAX refers to interoperable
implementations of the IEEE 802.16
family of wireless-networks standards
ratified by the WiMAX Forum.
 There were some earlier version of Wimax
that were used for testing purposes:
802.16a ,802.16b ,802.16c .
 The current versions are
802.16d (FIXED)
802.16e (MOBILE).

20.  It provides connectivity to the consumer equipments
 Base station consist of wireless electronic tower.
 Coverage area theoretically up to 50km but practically
10 km
ASN: ACEESS SERVING NETWORK
 802.16 interface network entry and handover
 Radio Resource Management & Admission ctrl.
 L2 Session/mobility management
 Forwarding to selected CSN

21. ASN-GW:
 network optimization
 forwarding of all subscriber traffic
 routing to the selected CSN
CSN:
 IP & traffic management
 QoS & Policy
 Billing control
 support for roaming between different NSPs