Associate Professor
Dept. of Electrical and Electronic Engineering
University of Dhaka
Dr.
Mohammad
J
unaebur
R
ashid (
JR
)
ICT3207: Cellular and Mobile Communication (3.0 Cr)
Course Teacher
Bangladesh University of Professionals
2
Lecture 03
Important Research Topic
ICT3207: CMC
• Interference :
Radio transmission cannot be protected against interference using shielding as this
is done in coaxial cable or twisted pair.
• Regulations and spectrum :
Frequencies have to be coordinated, and unfortunately, only a very limited amount
of frequencies are available.
• Low bandwidth :
Although they are continuously increasing, transmission rates are still very low for wireless devices compared to desktop systems.
• High delays, large delay variation :
A serious problem for communication protocols used in today’s Internet (TCP/IP)
Lecture 03
Important Research Topic
ICT3207: CMC
Lower security, simpler to attack :
Not only can portable devices be stolen more easily, but the radio interface is also
prone to the dangers of eavesdropping (secretly listen to a conversation).
Shared medium :
Radio access is always realized via a shared medium. As it is impossible to have a
separate wire between a sender and each receiver, different competitors have to ‘fight’ for the medium.
Ad-hoc networking :
Wireless and mobile computing allows for spontaneous networking with prior set-up of an infrastructure. However, this raises many new questions for research: routing on the
4
Lecture 03
A Simplified Reference Model
Lecture 03
A Simplified Reference Model
ICT3207: CMC
• A personal digital assistant (PDA) which provides an example for a wireless and portable
device.
• This PDA communicates with a base station in the middle of the picture.
• The base station consists of a radio transceiver (sender and receiver) and an interworking
unit connecting the wireless link with the fixed link.
• End-systems, such as the PDA and computer in the example, need a full protocol stack
comprising the application layer, transport layer, network layer, data link layer, and
physical layer.
• Applications on the end-systems communicate with each other using the lower layer
services.
• Intermediate systems, such as the interworking unit, do not necessarily need all of the
6
Lecture 03
A Simplified Reference Model
ICT3207: CMC
Physical layer
• This is the lowest layer in a communication system and is responsible for the conversion
of a stream of bits into signals that can be transmitted on the sender side.
• The physical layer of the receiver then transforms the signals back into a bit stream.
• For wireless communication, the physical layer is responsible for
frequency selection
generation of the carrier frequency
signal detection
modulation of data onto a carrier frequency and
Lecture 03
A Simplified Reference Model
ICT3207: CMC
Data link layer
• The main tasks of this layer include,
accessing the medium
multiplexing of different data streams
correction of transmission errors and
synchronization.
• The data link layer is responsible for a reliable point-to-point connection between two
devices or a point-to-multipoint connection between one sender and several receivers.
Network layer
• This third layer is responsible for routing packets through a network or establishing a
connection between two entities over many other intermediate systems. Important topics are
addressing , routing, device location, and
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Lecture 03
A Simplified Reference Model
ICT3207: CMC
Transport layer :
• This layer is used in the reference model to establish an end-to-end connection. Topics like,
quality of service
flow and congestion control are relevant
• Especially if the transport protocols known from the Internet, TCP and UDP, are to be used
over a wireless link.
• Application layer :
• Finally, the applications are situated on top of all transmission oriented layers. Topics of
interest in this context are,
service location, support for multimedia applications
adaptive applications and
wireless access to the world wide web using a portable device.
• Very demanding applications are video (high data rate) and interactive gaming (low jitter,
Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
• 1G: First generation cellular phone technology, analog, Advanced Mobile Phone Service (
AMPS)
• 2G: Second Generation digital technology, voice centric, TDMA, CDMA, GSM
• 2.5G: Second Generation with upgrades for speed, packet focus (e.g. GPRS layered on top of GSM)
Data rates from 56 up to 114 Kbps
• 3G: Third generation, data centric, packet based optimized for high bandwidth, WCDMA
and UMTS
• 4G: Based on an all-IP packet switched network
• G in 1G, 2G, 3G and 4G stands for the “Generation” of the mobile network. Today, mobile
operators have started offering 4G services in the country.
• A higher number before the 'G' means more power to send out and receive more
information and therefore the ability to achieve a higher efficiency through the wireless
10
Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
1G TECHNOLOGY
1
G TECHNOLOGY• 1G refers to the first generation of wireless telephone technology, mobile
telecommunications which was first introduced in 1980s and completed in early 1990s.
• It's Speed was up to 2.4 kbps.
• It allows the voice calls in 1 country.
• 1G network use Analog Signal.
• AMPS was first launched in USA in 1G mobile systems.
• Poor Voice Quality, Poor Battery Life, Large Phone Size
• No Security
• Limited Capacity
• Poor Handoff Reliability
Drawbacks
Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
1G TECHNOLOGY
2
G TECHNOLOGY• 2G technology refers to the 2nd generation which is based on GSM. • It was launched in Finland in the year 1991.
• 2G network use digital signals. • It’s data speed was upto 64 kbps.
Features Includes:
• It enables services such as text messages, picture messages and MMS (multi media
message).
• It provides better quality and capacity .
• 2G requires strong digital signals to help mobile phones work. If there is no network coverage in any specific area, digital signals would weak.
• These systems are unable to handle complex data such as Videos.
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Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
1G TECHNOLOGY
Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
1G TECHNOLOGY
2.5
G TECHNOLOGY• 2.5G is a technology between the second (2G) and third (3G) generation of mobile
telephony.
• 2.5G is sometimes described as 2G Cellular Technology combined with GPRS.
Features Includes:
Phone Calls
Send/Receive E-mail Messages
Web Browsing
Speed : 64-144 kbps
Camera Phones
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Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
3
G TECHNOLOGY• 3G technology refer to third generation which was introduced in year 2000s.
• Data Transmission speed increased from 144 kbps – 2 Mbps.
• Typically called Smart Phones and features increased its bandwidth and data transfer rates
to accommodate web-based applications and audio and video files.
• Providing Faster Communication
• Send/Receive Large Email Messages • High Speed Web / More Security
• Video Conferencing / 3D Gaming
• TV Streaming/ Mobile TV/ Phone Calls
• Large Capacities and Broadband Capabilities
Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
3
G TECHNOLOGY• Expensive fees for 3G Licenses Services
• It was challenge to build the infrastructure for 3G • High Bandwidth Requirement
• Expensive 3G Phones.
• Large Cell Phones • Vendor driven
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Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
4G TECHNOLOGY (Anytime ,Anywhere)
• 4G technology refer to or short name of fourth Generation which was started from 2000s.
• Capable of providing 100 Mbps – 1 Gbps speed.
• High QoS and High Security
• Provide any kind of service at any time as per user requirements, anywhere.
Features Include:
More Security
High Speed
High Capacity
Low Cost Per-bit etc.
• One of the basic term used to describe 4G is MAGIC.
Mobile Multimedia Anytime Anywhere
Global Mobility Support Integrated Wireless Solution
Customized Personal Services
Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
4G TECHNOLOGY (Anytime ,Anywhere)
• Battery uses is more
• Hard to implement
• Need complicated hardware
• Expensive equipment required to implement
next generation network.
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Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
Technology 3G 4G
Data Transfer Rate 3.1 MB/sec 100 MB/sec
Internet Services Broadband Ultra Broadband
Mobile - TV Resolution Low High
Bandwidth 5-20 MHz 100 MHz
Frequency 1.6-2 GHz 2-8 GHz
Download and upload 5.8 Mbps 14 Mbps
Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
• 5G technology refer to short name of fifth Generation which
was started from late 2010.
• 5G refers to the next and newest mobile wireless standard based
on the IEEE 802.11ac standard of broadband technology,
although a formal standard for 5G is yet to be set.
• Complete wireless communication with almost no limitations.
• It is highly supportable to WWWW (Wireless World Wide
Web).
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Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
• High Speed, High Capacity
• 5G technology providing large broadcasting of data in Gbps . • Multi - Media Newspapers, watch T.V. programs with the clarity
as to that of an HD Quality.
• Faster data transmission that of the previous generations. • Large Phone Memory, Dialing Speed, clarity in Audio/Video.
• Support interactive multimedia , voice, streaming video, Internet
and other
• 5G is More Effective and More Attractive.
5G TECHNOLOGY
Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
5G TECHNOLOGY
22
Lecture 03
All those Gs: 1G, 2G, 2.5G, 3G, 4G, 5G
ICT3207: CMC
