College of Engineering

Robert Akl, D.Sc.Robert Akl, D.Sc.

Department of Computer Science and

Engineering

Department of Computer Science and

Engineering

10/8/2004 2

OutlineOutline

• WiFi

• Access Point Selection

• Traffic Balancing

• Multi-Cell CDMA

• User Distribution Modeling

• Call Admission Control

• WiFi

• Access Point Selection

• Traffic Balancing

• Multi-Cell CDMA

• User Distribution Modeling

• Call Admission Control

10/8/2004 3

Three Story BuildingDemand Clusters

Three Story BuildingDemand Clusters

10/8/2004 4

Access Point Placement and Signal Level Map

Access Point Placement and Signal Level Map

10/8/2004 5

14 Access Points and 20 Demand Clusters

14 Access Points and 20 Demand Clusters

10/8/2004 6

AP Selection and Load BalancingAP Selection and Load Balancing

10/8/2004 7

Congestion Factor per APCongestion Factor per AP

10/8/2004 8

Average Congestion Across Network

Average Congestion Across Network

10/8/2004 9

Multi-Cell CDMA SimulationUniform User Distribution

Multi-Cell CDMA SimulationUniform User Distribution

10/8/2004 10

Extreme Cases Using Actual Interference Non-Uniform Distribution

Extreme Cases Using Actual Interference Non-Uniform Distribution

• Maximum network capacity of 1026 with best case non-uniform user distribution

• Maximum network capacity of 108 with worst case non-uniform user distribution

10/8/2004 11

Use 2-D Gaussian to Model User Distribution

Use 2-D Gaussian to Model User Distribution

• Mean = 0 and standard deviation = 200 • Mean = 0 and standard deviation = 500

10/8/2004 12

Use 2-D Gaussian to Model User Distribution

Use 2-D Gaussian to Model User Distribution

• Mean = 0 and standard deviation = 900 • Non-zero mean, standard deviation between 100-300

10/8/2004 13

Simulator – Call Arrival and Admission Module (Global CAC)

For Cells(i) = 1 to M

No

Yes

For Cell(i) = 1 to M Calculate )(ti

)()()( ttt iii

for Cells(i)=1 to M Is ffi CeC )()()( tAttR iii

Calculate

1)()(

1)()(

tntn

tAtA

ii

ii

i

For new call arriving in cell i Calculate Calculate

UiC

From call removal module

To call removal module

10/8/2004 14

Simulator – Call Removal Module (Global CAC)

if

Yes

1i

No

Yes

No

Is callstaying innetwork

Is call moving toadjacent cell

Yes

No

For Cells(i) = 1 to M

1 ii

1)()( tntn ii

Update

Calculate new i

1)()(

1)()(

tntn

tt

ii

ijij

U

Calculate new j

j

To call arrival and admission module

From call arrival and admission module

10/8/2004 15

Simulator – Call Arrival and Admission Module (Local CAC)

For Cells(i) = 1 to M

For Cell(i) = 1 to M Calculate )(ti

)()()( ttt iii

)()( tnNitA ii

)()()( ttntn iii No

Yes

)()()(

)()(

tAttR

tNtn

iii

ii

)()( tAt ii if

From call removal module

To call removal module

10/8/2004 16

Simulator – Call Removal Module (Local CAC)

if

Yes

1i

No

Yes

No

Is callstaying innetwork

Is call moving toadjacent cell

Yes

No

For Cells(i) = 1 to M

1 ii

1)()( tntn iiCalculate new i

1)()(

1)()(

tntn

tt

ii

ijij

Calculate new j

j

To call arrival and admission module

From call arrival and admission module

10/8/2004 17

Global CAC vs Local CAC

• Global

• Call admission based on all the calls present in the network.

• Slower.

• Inherently optimized.

• Adaptable.

• Complexity: O(M).

Local

• Call admission based on calls present in the cell under consideration only.

• Faster

• Optimized only for a given traffic distribution profile.

• Cannot compensate for big fluctuation in traffic.

• Complexity: O(1)

10/8/2004 18

10/8/2004 19

10/8/2004 20

PublicationsPublications

Journal

• R. Akl, A. Parvez, “Global versus Optimized Local Call Admission Control in Multi-cell CDMA Networks,” IEEE Transactions on Wireless Communications, paper no. TW04-624, under review.

• R. Akl, M. Hegde and M. Naraghi-Pour, “Mobility-based CAC Algorithm for Arbitrary Traffic Distribution in CDMA Cellular Systems,” IEEE Transactions on Vehicular Technology, paper no. VT-2003-00435, accepted.

Conference

• R. Akl, “ Subscriber Maximization in CDMA Cellular Networks,” Proceedings of CCCT 04: International Conference on Computing, Communications, and Control Technologies: CCCT 04, August 2004, vol 3, pp. 234-239.

• R. Akl and A. Parvez, “ Global versus Local Call Admission Control in CDMA Cellular Networks,” Proceedings of CITSA 04: Communications, Information and Control Systems, Technologies and Applications, July 2004, vol. 2, pp. 283-288.

• R. Akl and A. Parvez, “ Impact of Interference Model on Capacity in CDMA Cellular Networks,” Proceedings of SCI 04: Communication and Network Systems, Technologies and Applications, July 2004, vol. 3, pp. 404-408.

Journal

• R. Akl, A. Parvez, “Global versus Optimized Local Call Admission Control in Multi-cell CDMA Networks,” IEEE Transactions on Wireless Communications, paper no. TW04-624, under review.

• R. Akl, M. Hegde and M. Naraghi-Pour, “Mobility-based CAC Algorithm for Arbitrary Traffic Distribution in CDMA Cellular Systems,” IEEE Transactions on Vehicular Technology, paper no. VT-2003-00435, accepted.

Conference

• R. Akl, “ Subscriber Maximization in CDMA Cellular Networks,” Proceedings of CCCT 04: International Conference on Computing, Communications, and Control Technologies: CCCT 04, August 2004, vol 3, pp. 234-239.

• R. Akl and A. Parvez, “ Global versus Local Call Admission Control in CDMA Cellular Networks,” Proceedings of CITSA 04: Communications, Information and Control Systems, Technologies and Applications, July 2004, vol. 2, pp. 283-288.

• R. Akl and A. Parvez, “ Impact of Interference Model on Capacity in CDMA Cellular Networks,” Proceedings of SCI 04: Communication and Network Systems, Technologies and Applications, July 2004, vol. 3, pp. 404-408.

10/8/2004 21

Thank You!!Thank You!!

Questions?Questions?