Transcript [+1 +1 +1 +1], [+1 −1 +1 −1], [+1 +1 −1 −1], and [+1 −1 −1 +1].

Cellular Technology
Introduction to Cellular Technology
 The development of information and communication
technology is very fast.
 Communication use cables becoming abandoned.
 Humans are no dependent on technology 'wires'.
 Wireless networks have shifted the role of a wired
network.
 By carrying excellence in practicality, efficiency and
effectiveness, the wireless network has been
successfully satisfy its user.
Introduction to Cellular Technology (2)
• Cellular network technology evolved from analog to digital systems, from circuit
switching into packet switching.
• The evolution of mobile technology is divided into:
• 1G:
AMPS (Advanced Mobile Phone System)
• 2G:
GSM (Global System for Mobile Communication)
• 2.5G:
GPRS (General Packet Radio System)
• 3G:
UMTS (Universal Mobile Telecommunication System)
• 3.5G:
HSDPA (High Speed Downlink Packet Access)
• 4G:
LTE (Long Term Evolution)
WIRELESS Classification
Non
Cellular
Fixed
Wireless
contoh :
point to point communication, infra
red communication, LMDS,
Microwave communication
contoh :
Cellular
Wireless
Communication
Non
Cellular
Mobile
Wireless
PHS, CT2, PACS, DCS1800,
DECT
contoh :
paging system (ERMES, NTT, NEC)
, dispatching system, PAMR (Public
Access Mobile Radio) dsb
contoh :
Cellular
GSM, CDMA/IS-95, AMPS, UMTS,
PHS, DCS1800, NMT450, TACS,
C-450, dsb
Mobile Communications Systems
Requirement
There is at least one mobile terminal in communication
at the beginning
 High transmit power
 Antenna as high as possible
 Cell coverage profuse
 Handoff concept does not exist
Early Generation of Mobile Communications Systems
The Weakness
 Cost is expensive because it
requires high power amplifier and
antenna height
 Leisure customers interrupted when
switching coverage
 Low capacity
Radio tow er
Radio tow er
 Low spectrum efficiency
1G: AMPS (Advanced Mobile Phone System)

AMPS is the first generation of cellular technology.

Using analog technology and serve only voice communications.

Work on the 800 MHz frequency band

Access method use FDMA (Frequency Division Multiple Access).

AMPS technology start to be used in 1970 as the invention of the
microprocessor for wireless communication.

The increasing number of customers can not be accommodated first
generation.
2G: GSM (Global System for Mobile Communication)
GSM Frame Structure
1 multiframe for signalling
51 TDMA frame = 235.38 ms
0
1
2
49
1 multiframe for speech/data
26 TDMA frame = 120 ms
50
0
1
2
8 TS = 1 TDMA frame = 4.615 ms
0
1
2
3
4
5
6
1 TS
BURST = Contents of Time Slot
156.25 bit = 576.88 s
( 1 bit = 3.692 s )
7
24
25
2.5G: GPRS (General Packet Radio System)
 GPRS network is a result of the development of GSM
 Theoretically, the data rate can reach 171.2 kbps and the actual
data rate can be approximately 115 kbps.
 GPRS is a technology that is “always on”, meaning that the user is
always connected and does not need to dial up to gain the
connection again.
 The total cost will be charged based only on the amount of data
transmitted
 GPRS technology enables accessing of the Internet via mobile
telephone.
 GPRS is developed using GSM technology and therefore the speed
of data for Internet connection using GPRS is not quite
satisfactory.
3G: UMTS (Universal Mobile Telephone Standard)
3G: UMTS (Universal Mobile Telecommunication System)
 This generation is better known as WCDMA (Wideband - Coded Division Multiple Access).
 Data transmission rates up to 2 Mbps offered to fixed users with a wide bandwidth of 5 MHz.
 The user is allowed to get varied bandwidth according to the user demand which is one of
the excellent features of UMTS networks.
 One of the most famous examples of services, 3G video call which is the image of our friends
talk can be seen from our 3G mobile phone.
 Other services are, video conferencing, video streaming, both for Live TV and video portal,
Video Mail, PC to Mobile, and Internet Browsing.
3.5G: HSDPA (High Speed Downlink Packet Access)

HSDPA is an evolution of UMTS, HSDPA network architecture that still
use the UMTS network architecture.

Technology 3.5 G or also called super 3G is an improvement of the 3G
technology, especially in increasing the speed of data transfer over 3G
technology (> 2 Mbps) so that it can serve multimedia
communications such as Internet access and video sharing.

The main purpose of HSDPA is to increase the capacity of the
transmitted data packet and reduce the delay of a data packet
transmission.

In the Indonesian market was at the 3.5G technology, which for the
generation 4G can not be implemented because not get permission to
use the frequency of government (still under preparation)
4G: LTE (Long Term Evolution)

In IP-based 4G technology will be capable of integrating the
entire system and the existing network.

Which may be given access speed 4G fluttering from 100 Mbps to
1 Gbps, both indoors and outdoors with QoS (Quality of Service)
are guaranteed a good, guaranteed security system, and the
delivery of real-time information, wherever and whenever.

4G technology is expected to meet the needs of wireless
applications, such as mobile TV, HDTV, and digital video
broadcasting.

LTE was first launched by TeliaSonera in Oslo and Stockholm on
December 14, 2009. LTE is a technology that was asked to
replace UMTS / HSDPA. LTE is expected to be standardized
globally mobile phone first.
Cellular System
Cellular System
 Communication
systems
are
used
to
provide
telecommunications services for mobile customers.
 Called cellular system because its service area is divided
into small areas called CELL.
 CHARACTERISTICS: The customer is able to move freely
within the service area while communicating without
termination.
Cellular System (2)
• An area (e.g city), is divided into several subareas (cells)
• Each average-sized cells 26 km2
• The scope of a hexagon-shaped cells and form
a large hexagon grid.
• Therefore, mobile phone and the base station
(BTS) using a low-powered transmitters, the
same frequencies can be reused in cells that
are not adjacent
• Each cell has a base station that consists of a
tower and a small building containing the
radio device
Area Splitting
• One cell divides into several subsel.
• Purpose: to divide an area that is too dense for the
services are still available
Cellular System Architecture
Cell
• The basic unit of the cellular
system
• Cell size depends on the area
Cluster
• A set of cells
• No channel frequency reuse
A typical network layout
The working principle of the cellular network
Handover
FDMA (Frequency Division Multiple Access)
•
FDMA divides the frequency slots into small canals that same
bandwidth, which is then used individually by the user.
•
Each user is the one with the other is not a mutual interference.
•
FDMA is used in 1G networks and continued on 2G network
technology in combination with TDMA.
•
1G only uses FDMA which allocates each user with different
frequencies.
•
Security level is very low and limited frequency allocation.
If the frequency is full, it does not allow for the addition of a new
user.
Channelization : FDMA
 In frequency-division multiple access (FDMA), the available
bandwidth is shared by all stations.
 Each station uses its allocated band to send its data. Each band is
reserved for a specific station.
 The band belongs to the station all the time. FDMA is a data link layer
protocol that uses FDM at the physical layer.
12.25
Frequency-division multiple access (FDMA)
12.26
Diagram of an FDMA system
FDMA Structure
45 MHz
ARFCN=1
890.2
MHz
914.8
MHz
200KHz
135KHz
UPLINK
•
•
•
•
•
•
ARFCN=1
ARFCN=124
Band Frekuensi =
Jumlah carrier
carrier spacing
Duplex Spacing
ARFCN
=
=
=
=
935.2
MHz
20.4
KHz
ARFCN=124
959.8
MHz
200KHz
135KHz
DOWNLINK
Downlink (BS  MS) 935.2 ~ 959.8 MHz
Uplink (MS  BS) 890.2 ~ 914.8 MHz
124
200KHz
45 MHz
1 ~ 124
TDMA (Time Division Multiple Access)
• In TDMA, frequency channels are not permanently
dedicated to mobile users individually, but it is used
together with other users with just a different time.
• The time difference is divided into sections called TDMA
timeslot, which then will be given individually to the
mobile user.
• TDMA systems used in GSM mobile network system
Channelization : TDMA
 In time-division multiple access (TDMA), the entire bandwidth is just
one channel.
 The stations share the capacity of the channel in time. Each station is
allocated a time slot during which it can send data.
 TDMA is a data link layer protocol that uses TDM at the physical layer.
TDMA is used in the cellular telephone network
12.30
Time-division multiple access (TDMA)
12.31
Operation of a TDMA system
ARFCN atau “Absolute Radio Frequency Channel Number” adalah nomer channel yang
berurutan yang digunakan untuk mengidentifikasi carrier yang berbeda.
Hubungan antara parameter ARFCN dan frekuensi carrier adalah sebagai berikut:
fUplink = 890 + 0.2*(ARFCN-1) MHz
fDownlink = fUplink + 45 MHz
TDMA Frame 4.615 ms
Timeslot
577us
3
4
5
User 1
6
7
0
User 2
1
2
3
4
5
User 1
6
7
0
User 2
1
2
3
4 5
User 1
Prinsip kerja Time-Division Multiple Access (TDMA)
Work Process of TDMA
P E R C A K A P A N
With one channel can carry a conversation eighth in a way to divide
the conversation into fragments called Timeslot,
A
Minal a'din wa faidzin
B
Budi sedang pergi ke rumah kakek
C
Hallo, bisa bicara dengan Nunung
D
E
ABCDEFGHIJKLM
Betul ya, jangan lupa ...
F
Nggak tau 'ah
G
Besok Aku datang, bah..
H
Ooo.... begitu...tho
BTS
Radio Tow er
Communication between the BTS and
the MS through the physical channel in
the form of a burst
RF
Channel
Frekuensi
slo
t
slo 0
t
slo 1
t
slo 2
t
slo 3
t
slo 4
t
slo 5
t
slo 6
t
slo 7
t0
slo
t
slo 1
t2
burst
Minal a'idin
Budi Sedang
Hallo, bisa bi
ABCDEFGHI
Betul ya, jan
Nggak tau ah
Besok aku da
Ooo.... begitu
wa faidzin
pergi ke ru
cara dengan
8 Percakapan, 8 Channel
time-Axis
Delapan percakapan -- satu channel
CDMA (Code Division Multiple Access)
• In CDMA, each mobile user will not be distinguished by frequency or
time, but according to a unique code.
• Base station and the mobile user should have the ability to identify
the code and read the information contained therein
• Information from the user changed from narrow narrowband signal
into a wideband signal width, by multiplying the high frequency
code called chiprate.
• Then the wideband signal is transmitted over a radio network, on
the receiving side after the wideband signal is received, the code is
translated back into the original information by multiplying it back
to the original high-frequency code.
• CDMA system is used in multiple access systems 3G (UMTS)
CDMA Network Structure
Wideband CDMA (WCDMA)
• W-CDMA system is a multiple access technology that is stocked in
a high bandwidth (5-5MHz), wider than the bandwidth of the
CDMA system
• This technology differs from conventional GSM system uses
frequency division available bandwidth and time slot.
• WCDMA can be said to be based broadband CDMA GSM is often
also known as Access Technology of UMTS (Universal Mobile
Telecommunication) is an implementation of 3G that can reach
speeds up to 2 Mbps.
WCDMA Network
CDMA
 Let us assume that four stations (1,2,3,4 with codes c1,c2,c3,c4) connected to the
same channel are sending data d1,d2,d3,d4.
 Let us assume that the assigned codes have two properties:
1. If we multiply each code by another, we get 0.
2. If we multiply each code by itself, we get 4(the number of stations)
 The stations send data
If any station, (say station2) wants to get data sent by another station (say
station1), station2 multiplies the data on the channel by the code of the sending
station (i.e c1) and divides the result by 4:
 Data received by station2= {(d1.c1+d2.c2+d3.c3+d4.c4).c1}x1/4 =d1
The code assigned to each station is a sequence of numbers called chips.
12.39
Simple idea of communication with code
12.40
Chip sequences
12.41
Data representation in CDMA
12.42
Sharing channel in CDMA
12.43
Digital signal created by four stations in CDMA
12.44
Decoding of the composite signal for one in CDMA. The Fig. shows how station 3
can detect the data sent by station2.
12.45
Example 12.6
Find the chips for a network with
a. Two stations
b. Four stations
Solution
We can use the rows of W2 and W4 :
a. For a two-station network, we have
[+1 +1] and [+1 −1].
b. For a four-station network we have
[+1 +1 +1 +1], [+1 −1 +1 −1],
[+1 +1 −1 −1], and [+1 −1 −1 +1].
12.46
Example 12.7
What is the number of sequences if we have 90 stations in
our network?
Solution
The number of sequences needs to be 2m. We need to
choose m = 7 and N = 27 or 128. We can then use 90
of the sequences as the chips.
12.47
Example 12.8
Prove that a receiving station can get the data sent by a
specific sender if it multiplies the entire data on the
channel by the sender’s chip code and then divides it by
the number of stations.
Solution
Let us prove this for the first station, using our previous
four-station example. We can say that the data on the
channel
D = (d1 ⋅ c1 + d2 ⋅ c2 + d3 ⋅ c3 + d4 ⋅ c4).
The receiver which wants to get the data sent by station 1
multiplies these data by c1.
12.48
Example 12.8 (continued)
When we divide the result by N, we get d1 .
12.49
Tahapan Evolusi GSM/GPRS/EDGE/WCDMA-UMTS/HSDPA
Understanding for Packet Switching
 Data to be transmitted is divided into small parts
(packets) and then transmitted and the data is
converted back to the original.
 Can transmit thousands and even millions of packets
per second
 Allows for the use of the transmission channel
simultaneously by other users
 Transmission through the PLMN (Public Land Mobile
Network) by using an IP backbone
Evolution step GSM / GPRS/UMTS/HSDPA
Edge
Um
Um
Node-B
BSC
BTS
Edge TRX
PSTN
Network
GSM
INFRASTRUCTURE
PCU
Abis
HLR/AuC
EIR
MSC
HSDPA
RNC
HSDPA TRX
Iu
UMTS (WCDMA)
INFRASTRUCTURE
Border
Gateway (BG)
IWU
Serving GPRS
Support Node
(SGSN)
GPRS
INFRASTRUCTURE
GPRS
backbone
network
(IP based)
Lawful Interception
Gateway (LIG)
Inter-PLMN
network
SS7
Network
Internet
Gateway GPRS
Support Node
(GGSN)
Stages of Evolution CDMA
IS-95A CDMA
Voice, packet9.6/14.4 Kbps
IS-95B CDMA
Voice, packet64 Kbps
IS-2000 1X 144 Kbps
600 Kbps peak
IS-2000 1XEV-DO
600 Kbps; 2.4 Kbps peak IS-2000 1XEV-DV
2-5 Mbps peak
All IP
Any Questions