1. Mobile & Ad Hoc Network
Chandra Prakash
Assistant Professor
LPU
1Chandra Prakash, LPU
2. Objectives of the Chapter
Introduction
Fundamentals of Wireless Communication Technology
The Electromagnetic Spectrum
Radio Propagation Mechanisms
Characteristics of the Wireless Channel
Evolution of mobile Cellular Networks
Generations of Cellular Mobile Communication
GSM, GPRS,CDMA ,PCS, UMTS
Wireless LANs, Wi-Fi
IEEE 802 Networking Standard
2 Chandra Prakash, LPU
4. It all started like this
• First telephone (photophone) – Alexander Bell, 1880
• First radio communication system – G. Marconi(1897)
• The first car mounted radio telephone – 1921
5. Going further
• 1946 – First commercial mobile radio-telephone service by Bell and
AT&T in Saint Louis, USA. Half duplex (PTT)
– Push-to-talk cellular calls provide half-duplex communications
while one person transmits, the other(s) receive. This combines
the operational advantages of PTT with the interference
resistance and other virtues of mobile phones.
• 1973 – First handheld cellular phone – Motorola.
• First cellular net Bahrein 1978
6. Introduction to cellular network
A cellular network
Radio network distributed over land areas called cells,
Each cell served by at least one fixed location transceiver known
as a cell site or Base Station(BS).
When joined together these cells provide radio coverage over a
wide geographic area.
Enables a large number of portable transceivers (e.g., mobile
phones, pagers, etc.) to communicate with each other and with fixed
transceivers and telephones anywhere in the network, via base
stations, even if some of the transceivers are moving through more
than one cell during transmission.
9. Some Cellular Terminology
Cell- service area divided into small area known as cell
• Mobile station (MS) - Device used to communicate over the cellular
network.
• Base station transceiver (BST) - Transmitter/ receiver used to transmit/
receive signals over the radio interface section of the network.
• Base station controller (BSC) - Controls communication between a
group of BST's and a single MSC.
• Mobile switching centre (MSC) - The heart of the network, sets up and
maintains calls made over the network.
• Public switched telephone network (PSTN) - The land based section of
the network.
• Handoff/Handover : handover or handoff refers to the process of
transferring an ongoing call or data session from one channel connected
to the core network to another. Handoff decision made based on signal
strength.
10. Why Cellular ?
Cellular networks offer a number of advantages over alternative
solutions:
• Wireless access (very convenient)
• Access from anywhere within the coverage area.
• Reduced power use:
• Low power radio (hence better portability and more talk-time per battery
charge)
• ―Spectral efficiency‖ (more users in a limited frequency band) through
frequency reuse:
• increased capacity
• larger coverage area
• reduced interference from other signals
11. Cellular principles
In a cellular radio system, a land area to be supplied with radio service is
divided into regular shaped cells, which can be hexagonal, square, circular
or some other irregular shapes, although hexagonal cells are conventional.
Each of these cells is assigned multiple frequencies (f1 - f6) which have
corresponding radio base stations.
Example of frequency reuse factor or pattern 1/4
The group of frequencies can be reused in other cells, provided that the
same frequencies are not reused in adjacent neighbouring cells as that would
cause co-channel interference. This increased the capacity in a cellular
network.
12. Cont…
• In a standard FDMA system, there must be at least a one cell gap between
cells which reuse the same frequency.
• The frequency reuse factor is the rate at which the same frequency can be
used in the network.
• It is 1/K where K is the number of cells which cannot use the same
frequencies for transmission. Common values for the frequency reuse
factor are 1/3, 1/4, 1/7, 1/9 and 1/12 (or 3, 4, 7, 9 and 12 depending on
notation).
13. Generations of Cellular Mobile
Communication
Cellular mobile communication has generations:
– Generation (0)
– Generation # 1
– Generation #2
– Generation #2.5
– Generation #3
– Generation #4
14. Generation 0 (0g)
• Radio Telephone -1945
• Not officially categorized as mobile phones, since they did not
support the automatic change of channel frequency during calls,
which allows the user to move from one cell (the base station
coverage area) to another cell, a feature called "handover".
• Technologies used in pre cellular systems included the Push to
Talk (PTT or manual), Mobile Telephone System (MTS), Improved
Mobile Telephone Service (IMTS), and Advanced Mobile Telephone
System (AMTS) systems.
15. First generation (1G)
Radio signals that 1G networks use are analog [routines for sending
voice] ,
Mostly telephony only:
Virtually no data capability other than special device with analog
modem.
In 1G network, voice calls were simply modulated to a higher
frequency, typically to 150MHz and up.
No International roaming
All systems are incompatible
Little capacity – cannot accommodate masses of subscribers
This generation is now mostly obsolete.
16. First Generation Technology
• 1G system deployed in US and canada was known as AMPS.
• Advanced Mobile Phone System (AMPS)
– AMPS is an analog cellular phone system using FDMA.
– A total of 40MHz of spectrum was allocated from the 800MHz band by the Federal
Communications Commission (FCC) for AMPS.
– It was first deployed in Chicago, with a service area of 2100 square miles .
– AMPS offered 832 full duplex channels, with a data rate of 10 kbps.
– Although omnidirectional antennas were used in the earlier AMPS implementation, it was
realized that using directional antennas would yield better cell reuse.
– A 7-cell reuse pattern was adopted for AMPS.
– Designed for grade of service (GoS) of 2% blocking.
• In Europe, TACS (Total Access Communications System) was introduced
with 1000 channels and a data rate of 8 kbps.
• AMPS and TACS use the frequency modulation (FM) technique for radio
transmission
17. Second Generation (2G)
• A new design was introduced into the mobile switching center of second-
generation systems.
• The use of base station controllers (BSCs) lightens the load placed on the
MSC (mobile switching center) found in first-generation systems
• In addition to enhancements in MSC design, the mobile-assisted handoff
mechanism was introduced .
• In 2G, voice communications were digitally encrypted.
• Allowed enhanced data services
– The data capability includes Internet access and picture sharing.
• Support some limited data communications, such as Fax and short
messaging service (SMS)
18. Second Generation (2G)
• Increased capacity
• More security
• Compatibility
Compared to first-generation systems, second-generation (2G) systems
use digital multiple access technology
Multiple access technology,
TDMA (time division multiple access) and
CDMA (code division multiple access).
Global System for Mobile Communications, or GSM , uses TDMA
technology to support multiple users
19. Examples of 2G
• A 2G system is called personal communications services (PCS) in
marketing literature.
• Global System for Mobile (GSM) used in Europe ,
• Cordless Telephone
• Personal Access Communications Systems (PACS),
• Digital European Cordless Telephone (DECT),
• IS-36 used in US.
• Personal Digital communication (PDC) in Japan.
21. What is GSM
Global System for Mobile (GSM) is a second generation
cellular standard developed to cater voice services and
data delivery using digital modulation
More than 800 million end users in 212 countries (Asia,
Africa, Europe,Australia,America, India etc..) and
representing over 70% of today's digital wireless market.
source: GSM Association
22. • Developed by Group Spéciale Mobile in1982
Aim : to replace the incompatible analog system
• Presently the responsibility of GSM standardization resides with special mobile
group under ETSI ( European telecommunication Standards Institute )
• Under ETSI, GSM is named as ― Global System for Mobile communication‖
• Phase I of GSM specifications was published in 1990
• Commercial service started in mid-1991
• More than 1300 million subscribers in world and 45 million subscriber in India.
• GSM technology was the first one to help establish international roaming.
This enabled the mobile subscribers to use their mobile phone connections in
many different countries of the world’s is based on digital signals ,unlike 1G
technologies which were used to transfer analogue signals.
GSM Since Beginning
23. GSM
GSM in World GSM in India
Figures:March,2005
37%
1%
4%43%
4%
3%
3%
3%(INDIA)
3%
ArabWorld
AsiaPacific
Africa
EastCentralAsia
Europe
Russia
India
NorthAmerica
SouthAmerica
Figures: March 2005
Bharti
27%
BSNL
22%
Spice
4%
IDEA
13%
Hutch
19%
BPL
6%
Aircel
4%
Reliance
3%
MTNL
2%
Bharti
BSNL
Hutch
IDEA
BPL
Aircel
Spice
Reliance
MTNL
25. Advantages of GSM over Analog system
Capacity increases
Reduced RF transmission power and longer battery life.
International roaming capability.
Better security against fraud (through terminal validation and user
authentication).
Encryption capability for information security and privacy.
Compatibility with ISDN,leading to wider range of services
Integrated Services Digital Network (ISDN) is a set of
communications standards for simultaneous digital transmission of voice,
video, data, and other network services over the traditional circuits of
the public switched telephone network(PSTN).
26. Advantages
Uses radio frequency efficiently, Due to digital radio path it is more
tolerable to disturbance.
Speech quality much better than analog system
Data transmission is supported throughout the GSM system
Speech is encrypted and subscriber information security is
guaranteed.
GSM usesTDMA technology to support multiple users.
27. GSM Services (3 Types)
Tele-services :
Telecommunication services that enable voice communication via mobile
phones
Offered services
Mobile telephony
Emergency calling
Bearer or Data Services
Include various data services for information transfer between GSM and
other networks like PSTN[Public switched telephone n/w.], ISDN
[Integrated services digital n/w] etc at rates from 300 to 9600 bps
Short Message Service (SMS)
up to 160 character alphanumeric data transmission to/from the mobile
terminal
Voice mailbox
Electronic mail
28. GSM Services
SUPPLIMENTRY SERVICES
Call related services :
• CallWaiting- Notification of an incoming call while on the
handset
• Call Hold- Put a caller on hold to take another call
• Call Barring-All calls, outgoing calls, or incoming calls
• Call Forwarding- Calls can be sent to various numbers defined
by the user
29. Architecture of GSM Network Structure
GSM System Architecture-I
Mobile Station (MS)
Mobile Equipment (ME)
Subscriber Identity Module (SIM)
Base Station Subsystem (BSS)
Base Transceiver Station (BTS)
Base Station Controller (BSC)
Network Switching Subsystem(NSS)
Mobile Switching Center (MSC)
Home Location Register (HLR)
Visitor Location Register (VLR)
Authentication Center (AUC)
Equipment Identity Register (EIR)
• PSTN: Public switched telephone
network (telephone lines, fiber optic
cables, microwave transmission links, cellular
networks, communications satellites)
• ISDN: Integrated Services Digital Network
(digital transmission of voice, video, data, and
other network services)
30. TERMINOLOGIES:
• BTS: BaseTransceiver Stations (Cell Site)
• MSC: Mobile Switching Center
• HLR: Home Location Register
• VLR:Visiting Location Register
• EIR: Equipment Identity Register
• IMSI(International Mobile Subscriber Identity) -> stored in SIM
(Subscriber Identity Mobile)
• AUC:Authentication Centre
31. The Gateway Mobile Switching Centre (GMSC) is a special kind of MSC that is
used to route calls outside the mobile network. Whenever a call for a mobile
subscriber comes from outside the mobile network, or the subscriber wants to
make a call to somebody outside the mobile network the call is routed through the
GMSC.
32. GSM System Architecture-I
1. Mobile Station (MS)
1.1 Mobile Equipment (ME)
1.2 Subscriber Identity Module (SIM)
2. Base Station Subsystem (BSS)
2.1 BaseTransceiver Station (BTS)
2.2 Base Station Controller (BSC)
3. Network Switching Subsystem(NSS)
3.1 Mobile Switching Center (MSC)
3.2 Home Location Register (HLR)
3.3Visitor Location Register (VLR)
3.4Authentication Center (AUC)
3.5 Equipment Identity Register (EIR)
33. System Architecture
1. Mobile Station (MS)
1.1 Mobile Equipment (ME)
Portable, vehicle mounted,
hand held device
Uniquely identified by an
IMEI (International Mobile
Equipment Identity)
Voice and data transmission
Monitoring power and signal
quality of surrounding cells
for optimum handover
Power level : 0.8W – 20W
160 character long SMS.
1.2 Subscriber Identity Module
(SIM)
Smart card contains the
International Mobile Subscriber
Identity (IMSI)
Allows user to send and receive
calls and receive other subscribed
services
Encoded network identification
details - Key Ki,Kc andA3,A5 and
A8 algorithms
Protected by a password or PIN
Can be moved from phone to
phone – contains key information
to activate the phone
34. System Architecture
2. Base Station Subsystem (BSS)
2.1 BaseTransceiver Station
(BTS):
Encodes,encrypts,multiplexes,
modulates and feeds the RF
signals to the antenna.
Frequency hopping
Communicates with Mobile
station and BSC
Consists ofTransceivers (TRX)
units
2.2 Base Station Controller
(BSC)
Manages Radio resources for
BTS
Assigns Frequency and time
slots for all MS’s in its area
Handles call set up
Transcoding and rate
adaptation functionality
Handover for each MS
Radio Power control
It communicates with MSC
and BTS
35. System Architecture
3. Network Switching Subsystem(NSS)
3.1 Mobile Switching Center
(MSC)
Heart of the network
Manages communication between GSM
and other networks
Call setup function and basic switching
Call routing
Billing information and collection
Mobility management
- Registration
- Location Updating
- Inter BSS and inter MSC call handoff
MSC does gateway function while its
customer roams to other network by
using HLR/VLR.
3.2 Home Location
Registers (HLR)
permanent database about
mobile subscribers in a large
service area(generally one per
GSM network operator)
database contains
IMSI,MSISDN,prepaid/postp
aid,roaming
restrictions,supplementary
services.
36. System Architecture
3.Network Switching Subsystem
3.3Visitor Location Registers
(VLR)
Temporary database which
updates whenever new MS
enters its area, by HLR database
Controls those mobiles roaming
in its area
Reduces number of queries to
HLR
Database contains
IMSI,TMSI,MSISDN,MSRN,Loc
ationArea,authentication key
3.4 Authentication Center
(AUC)
Protects against intruders in
air interface
Maintains authentication keys
and algorithms and provides
security triplets (
RAND,SRES,Kc)
Generally associated with
HLR
37. System Architecture
3.Network Switching Subsystem
3.5 Equipment Identity Register (EIR)
Database that is used to track handsets using the IMEI (International
Mobile Equipment Identity)
Only one EIR per PLMN (public land mobile network )
38. GSM Specifications-1
GSM 900
Mobile to BTS (uplink): 890-915 MHz
BTS to Mobile(downlink):935-960 MHz
Bandwidth : 2* 25 MHz
GSM 1800
Mobile to BTS (uplink): 1710-1785 MHz
BTS to Mobile(downlink) 1805-1880 Mhz
Bandwidth : 2* 75 MHz
GSM 1900
GSM450
39. Security in GSM
On air interface, GSM uses encryption andTMSI instead of IMSI.
SIM is provided 4-8 digit PIN to validate the ownership of SIM
3 algorithms are specified :
-A3 algorithm for authentication
-A5 algorithm for encryption
-A8 algorithm for key generation
41. Cellular System vs. Personal Communication
System/Network (PCS/PCN)
Personal Communication Services [PCS] is a system, very similar to
Cellular Phone Service with great emphasis on personal services
(such as Paging, Caller ID, and E-mail) and mobility
PCS can be defined in a broader sense as a set of capabilities that
allows some combination of personal mobility and service
management.
Originated in UK, to improve its competitiveness in the field
42. PCS
PCS has smaller Cell size, therefore, requires more infra-structure
PCS works in 1.85-1.99 GHz band
PCS usesTDMATechnology but with 200 KHz Channel
Bandwidth with eight time-slots[as compared to 30 KHz and 3
time-slots used by Digital Cellular Phone System IS-54/IS-136]
Several PCS systems have been developed to meet rapid growth prompted
by market demand. Most of them are connected to Public Switched
Telephone Network (PSTN) to integrate with the wired service.
Two of the most popular PCS systems are:
Cellular telephony
Cordless and low-tier PCS telephony
43. Personal communications services (PCSs)
PCS/PCN:
PCS calls for more personalized services whereas PCN refers to
Wireless Networking Concept- any person, anywhere, anytime
can make a call using PC.
PCS and PCN terms are sometime used interchangeably. In
Europe, the term "personal communication networks (PCNs)" is
used instead of PCS.
Form objectives for third-generation wireless
PCS handsets low power, small and light
Provide a limited range & mobility within Urban Centers
44. Personal Communication System (PCS)
A system where wired and wireless networks are integrated for
establishing communication.
PSTN: Public Switched Network.
MSC: Mobile Switching Center. Also called MTSO
(Mobile Telephone Switching Office).
BS: Base Station.
MS: Mobile Station. Also called MU (Mobile Unit)
or Mobile Host (MH).
HLR: Home Location Register.
VLR: Visitor Location Register.
EIR: Equipment Identify Register.
AC: Access Chanel.
PSTN
BS
VLR
HLR
EIR
AC
MSC (MTSO)MSC (MTSO)
MSMS Wireless component
45. 2.5 G Mobile Systems
• The move into the 2.5G world will begin with General Packet Radio
Service (GPRS).
GPRS is a radio technology for GSM networks that adds packet-
switching protocols with
– shorter setup time for ISP connections,
– and the possibility to charge by the amount of data sent, rather
than connection time.
• Packet switching is a technique whereby the information (voice or data) to
be sent is broken up into packets, of at most a few Kbytes each, which are then
routed by the network between different destinations based on addressing data
within each packet.
46. 2.5 G
• The next generation of data heading towards third generation and personal
multimedia environments builds on GPRS and is known as Enhanced
Data rate for GSM Evolution (EDGE).
• 2.75G was the name given to the evolution of EDGE (Enhanced Data
rates for GSM Evolution) or Enhanced GPRS (EGPRS).
• EDGE allow GSM operators to use existing GSM radio bands to
offer wireless multimedia IP-based services and applications at
theoretical maximum speeds of 384 kbps with a bit-rate of 48 kbps per
timeslot and up to 69.2 kbps per timeslot in good radio conditions.
Implementing EDGE will be relatively painless as it will require relatively
small changes to network hardware and software as it uses the same
TDMA frame structure, logic channel and 200 kHz carrier bandwidth as
today's GSM networks.
As EDGE progresses to coexistence with 3G wideband -CDMA, data rates
of up to ATM like speeds of 2 Mbps could be available.
48. Constraints with existing network… WHY
GPRS?
Data Rates too slow – about 9.6 kbps
Connection setup time too long
Inefficient resource utilization for bursty traffic
Proves expensive for bursty traffic utilization
No efficient method for packet transfers
49. GPRS
General Packet Radio Service:-Radio technology that adds
packet-switching protocols
GPRS is a step towards 3G and is often referred to as 2.5G
GPRS support flexible data transmission rates than GSM as well as
continuous connection to the network.
It works onTDMA & CDMA technology, depending upon the
multiplexing used.
Short for General Packet Radio Service, a standard for
wireless communications which runs at speeds up to 115 kilobits
per second, compared with current GSM (Global System for
Mobile Communications) systems’ 9.6 kilobits.
50. Cont…
GPRS, which supports a wide range of bandwidths, is an efficient
use of limited bandwidth and is particularly suited for sending and
receiving small bursts of data, such as e-mail andWeb browsing, as
well as large volumes of data.
It consists of a packet wireless access network and an IP-based
backbone. GPRS is designed to transmit small amounts of
frequently sent data or large amounts of infrequently sent data.
GPRS has been seen as an evolution toward UMTS (Universal
MobileTelecommunications Systems). Users can access IP services
via GPRS/GSM networks.
51. Comparison of GSM & GPRS
GSM GPRS
Data Rates 9.6 Kbps 14.4 to 115.2 Kbps
Modulation Technique GMSK
(Gaussian Minimum Shift Keying)
GMSK
(Gaussian Minimum Shift
Keying)
Billing Duration of connection Amount of data
transferred
Type of Connection Circuit – Switched Technology Packet - Switched
Technology
52. Benefits of GPRS
New Data Services
High Speed (Data Rate 14.4 – 115 kbps)
Efficient use of radio bandwidth
Circuit switching & Packet Switching can be used in
parallel
Constant connectivity
53. General Packet Radio Service (GPRS)
SGSN: A Serving GPRS Support Node is responsible for the delivery of data packets from
and to the mobile stations within its geographical service area.
GGSN : Gateway GPRS Support Node is responsible for the interworking between the
GPRS network and external packet switched networks, like the Internet and X.25 networks.
54. ARCHITECTURE
GPRS services include both point-to-point and point-to-multipoint
communications
GPRS Architecture is same as GSM except few hardware
modifications :
GPRS includes GSNs
SGSN : Serving GPRS Support Node
GGSN : Gateway GPRS Support Node
GPRS Register
55. SGSN(Serving GPRS Support Node)
Delivers data packets to mobile stations & vice-versa
Detect and Register new GPRS MS in its serving area
Packet Routing, Transfer & Mobility Management
Authentication, Maintaining user profiles
Its location register stores location info. & user profiles
56. GGSN – Gateway GPRS Support Node
Interfaces GPRS backbone network & external packet data networks.
The Gateway GPRS Support Node is the ―last port of call‖ in the GPRS
network before a connection between an ISP or corporate network’s
router occurs.
The GGSN is basically a gateway, router and firewall rolled into one.
57. GPRS in INDIA
BPL Mobile
Bharti Cellular
Hutchison Max
Hutchison Essar
Idea Cellular
58. GPRS characteristics
GPRS uses packet switched resource allocation
• resources allocated only when data is to be sent/received
• Flexible channel allocation
• one to eight time slots
• available resources shared by active users
• up and down link channels reserved separately
• GPRS and circuit switched GSM services can use same
time slots alternatively
Traffic characteristics suitable for GPRS
• Intermittent, bursty data transmissions
• Frequent transmissions of small volumes of data
• Infrequent transmission of larger volumes of data
60. (Enhanced Data rates for GSM
Evolution )
Referred as Enhanced GPRS or EGPRS
Inherits all features from GSM and GPRS.
Only difference is instead of binary (Gaussian minimum-shift keying)GMSK ,
it uses 8-PSK modulation (Phase-shift keying ) which triple the capacity
compared to GSM.
EDGE is considered a pre-3G radio technology
EDGE requires no hardware or software changes to be made in GSM core
networks. EDGE-compatible transceiver units must be installed and the base
station subsystem needs to be upgraded to support EDGE.
8-PSK is more susceptible to errors than GMSK, thus have 9 different
modulation and coding schemes, each designed for different quality control.
61. Third Generation (3G)
3G or 3rd generation mobile telecommunications is a generation of
standards for mobile phones and mobile Telecommunication services
fulfilling the International Mobile Telecommunications-2000 (IMT-
2000) specifications by the International Telecommunication Union .
Application services include wide-area wireless voice telephone, mobile
Internet access, video calls and mobile TV, all in a mobile environment.
3G: voice (circuit-switched) & data (packet-switched)
Third generation offers multi-media communication capabilities, at
higher bit rates, with improved spectrum efficiency.
The EDGE standard is the development of GSM towards 3G.
62. Third Generation Technology (3G)
Digital system with multimedia services including video phone and
relatively higher speed (say up to 1 Mbps) Internet access.
Permanent web connection upto 2Mbps
Internet, phone and media: 3 in 1
Wideband code division multiple access (W-CDMA) and UMTS are some
of 3G standard.
The standard based on GSM is called UMTS.
Universal Mobile Telecommunications System (UMTS) is a third
generation mobile cellular technology for networks based on
the GSM standard.
3G has just been launched in India and is available on select mobile
operators for select cities. But to access these services, a 3G compatible
mobile phone is required.
63. 3G
3G used completely different radio frequencies from 2G,
so it required different equipment to achieve the new high data
transfer rates.
Enormous costs of additional spectrum licensing fees delayed the
introduction of 3G in many countries.
3G data transfer rates are 384kbits/s to 2Mbits/s, so it allows for
previously unavailable services like video calls, video
conferencing, online conference call, mobile TV, online gaming etc.
65. (Universal Mobile Telecommunication
System)
The Universal MobileTelecommunications System (UMTS)
is commonly referred to as a third-generation system.
It was targeted to be deployed in 2002.
UMTS employs an ATM-based switching network
architecture and aims to provide services for both mobile and
fixed subscribers by common call-processing procedures.
Full packet driven architecture
For voice and for data transmissions.
Packet based networks allow for an increased amount of traffic on a
medium.
66. The UMTS architecture is split into 3 networks :
1. Core (switching) networks:
o The core network is responsible for performing switching
and transmission functions
2. Control (service) networks:
o The control network supports roaming through the
presence of mobility management functions
3. Radio Access networks.
o provides channel access to mobile users and performs radio
resource management and signalling
UMTS will include both terrestrial and global satellite
components.
Universal Mobile Telecommunication System
67. UMTS
Offers voice and data services the same as EDGE
Services offered will be classed into one of the following
Conversational Streaming Interactive Background
Real-Time Best-effort, guarantee of quality
delivery
Voice Streaming
Video
Web Pages MMS, SMS,
emails
UMTS
(Universal Mobile Telecommunication System)
68. UMTS
(Universal Mobile Telecommunication System)
3G is also known as UMTS (Universal Mobile
Telecommunication System)
UMTS usesWideband-Code Division MultipleAccess (W-CDMA)
Also known as “IMT-2000 Direct Spread”
Modulation is done with Quadrature phase shift keying (QPSK)
This encodes 2 bits with each change
Supports two modes of operation
Frequency Division Duplex (FDD)
Time Division Duplex (TDD)
69. UMTS
(Universal Mobile Telecommunication System)
The UMTS network comprises:
(a) the mobile terminal,
(b) the base transceiver station (BTS),
(c) the cell site switch (CSS),
(d) mobile service control points (MSCP), and
(e) the UMTS mobility service (UMS).
UMTS employs a hierarchical cell structure, with macrocells
overlaying microcells and picocells.
Highly mobile traffic is operated on the macrocells to reduce the
number of handoffs required.
UMTS aims to support roaming across different networks.
70. 3G UMTS
Types of Cells and Base station to use them
Macro Cell
These cover a large area and will give slow access
144 Kbps – max speed of 500 Km/h
Micro Cell
These should cover a medium area
384 Kbps max speed 120 Km/h
Pico Cell
Less than 100 metres
2 Mbps – max speed of 10 Km/h
Difficult to predict
Actual distances and bandwidth depend on local conditions
72. 3G UMTS
Types of Cells and Base station to use them
Cells will operate in a hierarchy overlaying each other
Satellite
Macro-Cell
Micro-Cell
Urban
In-Building
Pico-Cell
Global
Suburban
74. Telecommunications
• Mobility
• Circuit switching services
• Packet switching services
UMTS
Internet
• Internet access
• E-mail
• Real-time images transfer
• Multimedia documents transfer
Contents
• Video on-demand
• Interactive video services
• Radio and television
• Entertainment services
• Location based services
Convergence of media, data & telecom
75. Node B
UTRAN
UMTS Basic Architecture Release 99
GMSC
HLR
PSTN/ISDN
BTS
GSM BSS
RNC
BSC
MSC/VL
R
SGSN
Circuit Domain
Packet Domain
INTRANETS
GGSN
Other PLMN
INTERNET
Radio Access Network Core Network
MS
UE
ME
ME
Universal Terrestrial Radio Access Network,
Radio Network Controller
76. Cont…
UMTS is also designed to offer data rate on-demand.
The network will react to a user's needs, based on his/her profile and
current resource availability in the network. UMTS supports the
virtual home environment (VHE) concept, where a personal
mobile user will continue to experience a consistent set of services even
if he/she roams from his/her home network to other UMTS operators.
VHE supports a consistent working environment regardless of a user's
location or mode of access.
UMTS will also support adaptation of requirements due to different data
rate availability under different environments, so that users can continue
to use their communication services.
77. Fourth Generation
The next step in wireless communications.
A 4G system will be able to provide a comprehensive IP solution
where voice, data and streamed multimedia can be given to users
on an "Anytime, Anywhere" basis, and at higher data rates than
previous generations.
4G mobile phones are all set to provide data transfer rates of
100Mbit/s to 1Gbit/s,
Digital system with voice over-IP (VOIP) technology. That is, the services
are integrated into all IP network.
78. What is 4G?
• Fourth Generation Technology
– Faster and more reliable
– 100 Mb/s
– Lower cost than previous generations
– Multi-standard wireless system
– Bluetooth, Wired, Wireless
– Ad Hoc Networking
– IPv6 Core
– OFDM used instead of CDMA
– Potentially IEEE standard 802.11n
– Most information is proprietary
79. Fourth Generation Technology
One of the main ways in which 4G differed technologically from 3G was
in its elimination of circuit switching, instead employing an all-IP
network.
4G ushered in a treatment of voice calls just like any other type of
streaming audio media, utilizing packet switching
over internet, LAN or WAN networks via VoIP.
Concept of Global Village
84. Type of Networks
By Network Formation and Architecture
• Infrastructure-based network.
• Infrastructureless (ad hoc) network.
By Communication Coverage Area.
1. Wireless Wide Area Networks (Wireless WANs)
• Infrastructure-based networks
• Connections can be made over large geographical areas, across cities or even
countries
• Use of multiple antenna sites or satellite systems maintained by wireless service
providers.
• Examples :Cellular networks (like GSM networks or CDMA networks) and satellite
networks
87Chandra Prakash, LPU
85. Type of Networks
2. Wireless Metropolitan Area Networks (Wireless MANs).
– Referred as fixed wireless , infrastructure-based networks
– Enable users to establish broadband wireless connections among multiple locations ,for
example, among multiple office buildings in a city or on a university campus
– Serve as backups for wired networks
– Radio waves and infrared light can be used to transmit data.
3. Wireless Local Area Network (Wireless LANs)
– Enable users to establish wireless connections within a local area with in a 100 m range
– Provide flexible data communication systems that can be used in temporary offices or
other spaces that can operate in infrastructure-based or in ad hoc mode
– Include 802.11 (Wi-Fi) and Hiperlan2
4. Wireless Personal Area Networks (Wireless PANs).
– Enable users to establish ad hoc, wireless communication among personal wireless
devices such as PDAs, cellular phones, or laptops that are used within a personal
operating space, typically up to a 10 meter range.
– Two key Wireless PAN technologies are
• Bluetooth : is a cable-replacement technology that uses radio waves to transmit data
to a distance of up to 9–10 m,
• Infrared: connect devices within a 1 m range.
88Chandra Prakash, LPU
87. IEEE 802 Networking Standard
• we need to have set of rules/standards for the data to travel
from one computer to other computer.
• Its developed by IEEE (Institute of Electrical and Electronics
Engineers, Inc.)
• The number 802 was simply the next free number IEEE could
assign, though ―802‖ is sometimes associated with the date the first
meeting was held — February 1980.
• The standards such as IEEE 802 helps industry provide advantages
such as, interoperability, low product cost, and easy to manage
standards.
• IEEE standards deal with only Local Area Networks (LAN) and
Metropolitan Area Networks (MAN).
89. IEEE 802.11
• IEEE 802.11 is a set of standards for implementing wireless local
area network (WLAN) computer communication in the 2.4, 3.6 and
5 GHz frequency bands. They are created and maintained by
the IEEE LAN/MAN Standards Committee (IEEE 802)
• 802.11 specifies an over-the-air interface between a wireless
client and a base station or between two wireless clients. The
IEEE accepted the specification in 1997.
90. IEEE 802.11
There are several specifications in the 802.11 family:
• 802.11 — applies to wireless LANs and provides 1 or 2 Mbps transmission in
the 2.4 GHz band using either frequency hopping spread spectrum (FHSS) or
direct sequence spread spectrum (DSSS).
• 802.11a — an extension to 802.11 that applies to wireless LANs and provides
up to 54-Mbps in the 5GHz band. 802.11a uses an orthogonal frequency
division multiplexing encoding scheme rather than FHSS or DSSS.
• 802.11b (also referred to as 802.11 High Rate or Wi-Fi) — created a standard
of wireless LAN operations in 2.4 GHz industrial, scientific and medical
(ISM) Band , which is freely available for use throughout the world. This
standard known as Wi-Fi (Wireless-Fidelity).It can offer data rates of up-to
11 MBPS.
91. • 802.11e — a wireless draft standard that defines
the Quality of Service (QoS) support for LANs, and is an enhancement to
the 802.11a and 802.11b wireless LAN (WLAN) specifications. 802.11e
adds QoS features and multimedia support to the existing IEEE 802.11b
and IEEE 802.11a wireless standards, while maintaining full backward
compatibility with these standards.
• 802.11g — applies to wireless LANs and is used for transmission over
short distances at up to 54-Mbps in the 2.4 GHz bands.
• 802.11n — 802.11n builds upon previous 802.11 standards by adding
multiple-input multiple-output (MIMO). The real speed would be 100
Mbit/s (even 250 Mbit/s in PHY level), and so up to 4-5 times faster than
802.11g.
• 802.1X — Not to be confused with 802.11x (which is the term used to
describe the family of 802.11 standards) 802.1X is an IEEE standard for
port-based Network Access Control that allows network administrators to
restricted use of IEEE 802 LAN service access points to secure
communication between authenticated and authorized devices.