Transcript UMTS, air interface et modulation

14th June 2006
RANDAXHE Benjamin
1
Thanks to M CATTRYSSE Eric
Memoir
Presented by Randaxhe Benjamin
In order to receive
Electronics Bachelor Diploma
(Telecommunication oriented)
Academic year : 2005 ~ 2006
2
UMTS, air interface
et modulation
Presented by Benjamin Randaxhe
UMTS
 Overview
Air interface
 Generality
 Coding
 Power
Modulation
 UMTS
modulator
 RAKE receiver
14th June 2006
RANDAXHE Benjamin
4
UMTS
 Overview
Air interface
 Generality
 Coding
 Power
Modulation
 UMTS
modulator
 RAKE receiver
14th June 2006
RANDAXHE Benjamin
5
Universal Mobile Telecommunications System
3rd generation mobile
Multimedia services
High bitrate
New services : Video Call, TV,
internet browsing, games,…
14th June 2006
RANDAXHE Benjamin
6
14th June 2006
RANDAXHE Benjamin
7
UMTS
 Overview
Air interface
 Generality
 Coding
 Power
Modulation
 UMTS
modulator
 RAKE receiver
14th June 2006
RANDAXHE Benjamin
8
Dissociation by code
=> CDMA
Two codes are used
UMTS
1
1
1
1
1
1
1
 Channelisation
1
1
 Scrambling
1
1
1
1
Frequency is used
in every cell
14th June 2006
RANDAXHE Benjamin
=> WCDMA
9
14th June 2006
RANDAXHE Benjamin
10
Power
Time
UMTS USER 2
UMTS USER 1
Frequency
1920 MHz
5 MHz
Uplink Spectrum
1980 MHz
2110 MHz
5 MHz
Downlink Spectrum
2170 MHz
Duplex Spacing : 190MHz
Full duplex
Separate frequencies used for uplink
and downlink traffic
14th June 2006
RANDAXHE Benjamin
11
UMTS
 Overview
Air interface
 Generality
 Coding
 Power
Modulation
 UMTS
modulator
 RAKE receiver
14th June 2006
RANDAXHE Benjamin
12
bits
chips
Data +
CRC +…
Modulator
Channelisation
Scrambling
Clock
Channelisation
 OVSF
 Separation
channels
14th June 2006
of
Scrambling
 Pseudo
Noise codes
 Separation of
transmitters : MS or
Node B
RANDAXHE Benjamin
13
Cchan 1
User 1
Cscr
Cchan 2

User 2
UE3
UE2
Cchan 3
UE1
User 3
14th June 2006
RANDAXHE Benjamin
14
Cchan
Cscr 1
Cchan
Cscr 2
Cchan
Cscr 3
User 1
UE3
User 2
UE1
User 3
14th June 2006
UE2
RANDAXHE Benjamin
15
UMTS
 Overview
Air interface
 Generality
 Coding
 Power
Modulation
 UMTS
modulator
 RAKE receiver
14th June 2006
RANDAXHE Benjamin
16
Everyone use the same frequency
 Avoid
interference between Node B ’s
themselves
 Avoid « near-far effect »
Power
sent
Power
received
MAX
UE
1
UE
2
UE
3
min
UE
1
UE
2
UE
3
UE3
UE2
Power
sent
Power
received
UE1
UE
3
UE
1
14th June 2006
RANDAXHE Benjamin
UE
2
MAX
min
UE
1
UE
3
UE
2
17
Open loop
 Increases
power step by step
Closed loop
 Power
14th June 2006
is regulated 1500 time per second
RANDAXHE Benjamin
18
MS
Node B
Sent
33 dBm (2W)
-60 dBm (1 nanoW)
Received
-117 dBm (1,9.10-15W)
46 dBm (40W)
12 dBm (20mW)
-121 dBm (7,9.10-16W)
NB: Thermal noise
± -108 dBm (1,514 .10-14)
14th June 2006
RANDAXHE Benjamin
19
UMTS
 Overview
Air interface
 Generality
 Coding
 Power
Modulation
 UMTS
modulator
 RAKE receiver
14th June 2006
RANDAXHE Benjamin
20
DPDCH 1
DPDCH 2
DPDCH x
DPCCH
PDSCH
Cscr

PCCPCH
SCCPCH

AICH
PICH
CPICH
14th June 2006
SCH
RANDAXHE Benjamin
QPSK
Modulator
21
I
Data
Series
Parallel
Cchan
Power
Control

*j
14th June 2006
RANDAXHE Benjamin
Chips
jQ
22
DPDCH 1
DPDCH 2
DPDCH x
DPCCH
PDSCH
Cscr

PCCPCH
SCCPCH

AICH
PICH
CPICH
14th June 2006
SCH
RANDAXHE Benjamin
QPSK
Modulator
23
Two speparated signals:
 Data
 Control
HPSK Modulation
Channelisation
Scrambling
Data
Modulator
Control
*j
Channelisation
14th June 2006
RANDAXHE Benjamin
24
QPSK
14th June 2006
HPSK
RANDAXHE Benjamin
25
UMTS
 Overview
Air interface
 Generality
 Coding
 Power
Modulation
 UMTS
modulator
 RAKE receiver
14th June 2006
RANDAXHE Benjamin
26
Problems :
Reflected RF
Absorbed RF
Diffraction
14th June 2006
RANDAXHE Benjamin
27
With a reference channel, RAKE
receiver is able to detect and to
correct the corrupted signal
Data sent
Data
received
Data
corrected
Combiner
Rake #1
Rake #2
Original
signal is
found
Rake #3
14th June 2006
RANDAXHE Benjamin
28
Thank you
Presentation
and memoir
http://users.skynet.be/bk331357/umts/
Question
http://users.skynet.be/bk331357/umts/
Thank you