Its2002 presentation
-
Upload
almedeiroshotmail -
Category
Documents
-
view
213 -
download
0
description
Transcript of Its2002 presentation
![Page 1: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/1.jpg)
Frequency Reuse Efficiency and Admission Control in Multirate
Systems
Wireless Technologies Laboratory (WITEK) Department of Communications
School of Electrical and Computer Engineering State University of Campinas - São Paulo - Brazil
Álvaro Augusto M. de Medeiros (UNICAMP/SP) Prof. Michel Daoud Yacoub (UNICAMP/SP)
César Kyn D’Ávila (CEDET/ SP)
ITS 2002, Natal - RN, September 9, 2002
![Page 2: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/2.jpg)
Presentation Outline
Introduction Interference on Forward Link Relative Power and Admission Control Frequency Reuse Efficiency on CAC CAC Algorithm and an application
example Conclusion
![Page 3: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/3.jpg)
Introduction
Frequency Reuse Efficiency Related to system capacity and coverage 3G Services Forward link limited Multirate services with different QoS requirements
OCk
kk IP
PF+
=
![Page 4: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/4.jpg)
Interference on Forward Link
Cell j
rj
ri
ri
αδεjko
jT
kkSC rlPI
)(
)1( −=
∑≠=
=M
jii iko
iT
OC rlPI
1
)(
α
Same cell
Others cells
αα δδεjko
jT
kjko
jT
kkk rlP
rlPP
)()(
)1( +−=
![Page 5: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/5.jpg)
Relative Power
Signal-to-interference ratio Relative power
( )SCOC
jkoj
Tk
kkt
b
IIrlP
RW
IE
+
=
αδ )(
kk
kkk
Lχεεδ
++
=
![Page 6: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/6.jpg)
Relative Power
Jamming Margin
Lk parameter
α
∑≠=
=
M
jii i
jj
T
iT
k rr
PPL
1)(
)(
tB
kk IE
RW=χ
Depends on network topology, base stations’ transmission powers and propagation environment
![Page 7: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/7.jpg)
Relative Power
Relative power
kk
kkk
Lχεεδ
++
=
Depending on the users’ location, a new subscriber may not have access to all services
Higher bit rates demand
a higher fraction of the forward link total power
![Page 8: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/8.jpg)
Relative Power
Lk parameter in a four-tier network and PT
(i)/ PT (j)=1
0.0 0.2 0.4 0.6 0.8 1.00.0
0.2
0.4
0.6
0.8
1.0
α=4α=3
α=2
L k / L
k max
d/Rcell
α Lk (mean) Lk max
4 0.291 2.073 3 0.549 2.542 2 1.551 4.284
![Page 9: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/9.jpg)
Relative Power
Lk parameter in a four-tier network and PT
(i)/ PT (j)=1
α=4
-1.0 -0.5 0.0 0.5 1.0-1.0
-0.5
0.0
0.5
1.0
Lk/Lk max
Y
X
00.100.250.500.751.0
![Page 10: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/10.jpg)
Relative Power and CAC
Lk after user’s admission Relative power after user’s admission
α
∑≠= +
=+
M
jii ik
jk
tj
T
iT
k rr
PP
tL1 1
)(
)(
)()1(
1)()(
1)( )()()( ++ += t
jTkt
jTt
jT PPP δ
( )kkk tLtL δ−⋅=+ 1)()1(⇒
)()(
tLtL
kkk
kkk ++
+=
χεε
δ
![Page 11: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/11.jpg)
Fk and CAC
Fk after user’s admission Jamming margin values
kkkkkk
kkkkk tLtL
tLFχχεε
χεε)()(
)(+++
++=
Service Rk (Eb/It)k χk Voice 8 kbps 7 dB 95.77
Video 144 kbps 7 dB 5.32
Packet Data 384 kbps 10 dB 1
![Page 12: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/12.jpg)
Fk and CAC
Fk versus χk 4 tiers εk =0.5 α=4
0 20 40 60 80 1000.0
0.2
0.4
0.6
0.8
1.0α=4
Lk/Lk max=0,1; 0,2; ... 1,0
Reus
e effi
cienc
y (F k )
Jamming Margin (χk)
![Page 13: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/13.jpg)
Fk and CAC
Fk versus χk 4 tiers εk =0.5 α=2
0 20 40 60 80 1000.0
0.2
0.4
0.6
0.8
1.0α=2
Lk/Lk max=0,1; 0,2; ... 1,0
Reus
e Effi
cienc
y (F k )
Jamming Margin (χk)
![Page 14: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/14.jpg)
CAC using Lk and χk
Load Factor Subscriber’s contribution
∑=
=N
kk
1ρρ
−+=
k
kk
k
kk F
F1εχυρ
++
+=kkkk
kkk
k
kk L
Lχεε
χεχυρ
![Page 15: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/15.jpg)
CAC using Lk and χk
ρk versus Lk / Lk max 4 tiers εk =0.5 α=4
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
υk= 0.2 →1
υk= 0.2 →1
υk= 0.2, 0.5, 1
ρ k
Lk / Lk max
384 kbps 144 kbps 8 kbps
![Page 16: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/16.jpg)
Application example
Urban scenario (α=4), εk =0.5, ρmax=0.5, 4 tiers In this scenario, a packet data user has a
load factor contribution ρk=0.5 for Lk near zero. He must be confined within a maximum
distance dmax ≤ 0.3rcell
![Page 17: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/17.jpg)
Application example
Before admission: Possible scenario after admission:
dmax/Rcell 0.2 0.4 0.6 0.8 0.9 Existing voice users 10 10 10 5 5
Possible combinations of new video users dmax/Rcell
S1 S2 S3 S4 S5 0.2 - 1 1 - 3 0.4 - - 1 3 - 0.6 - - 1 - - 0.8 - 1 - - - 0.9 1 - - - -
Total users 1 2 3 3 3
![Page 18: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/18.jpg)
Conclusions
Frequency Reuse Efficiency must be calculated locally For higher bit rates or higher demands of
Eb/It , the required Fk has a considerable variation Fk is strongly dependent on the network
topology Which services and where within the cell they are
guaranteed
![Page 19: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/19.jpg)
Conclusions
An admission control algorithm must consider the value of the reuse efficiency according to subscriber’s location and requested service. A CAC algorithm was proposed based on the
capacity equation. Finally, we presented an example of
admission control for WCDMA services using this algorithm.
![Page 20: Its2002 presentation](https://reader031.fdocuments.net/reader031/viewer/2022032515/563db937550346aa9a9b2f5a/html5/thumbnails/20.jpg)
Questions and Comments
Contact: [email protected]
WITEK – DECOM/FEEC/UNICAMP
Campinas - São Paulo - Brasil