1Bernhard Walke, Peter Sievering

MESA Ad-Hoc Session, Copenhagen, Sept. 27, 2002

Research Interests in Mobile Broadband Ad-Hoc Networks

Bernhard Walke, Peter SieveringAachen University RWTH, www.comnets.rwth-aachen.de

CONTACT: Prof. Dr.-Ing. Bernhard WalkeKopernikusstrasse 16, 52074 Aachen, Germany

E-mail: Walke@ComNets.RWTH-Aachen.dePhone: +49 241 80 27910, Fax: +49 241 80 22242

2Bernhard Walke, Peter Sievering

ComNets Research Group

38 scientific assistants (fully employed) 40 to 50 students assistants (part time jobs) 35 master theses in 2001 > 45 scientific publications per year 600 – 800 ComNets paper downloads per month Partner in currently 7 European Research Projects:

VIRTUOS, FUTURE, DRIVE/OVERDRIVE, IPonAir, STRIKE, SAILOR, WWRI

Chair of Communication Networks (ComNets)Prof. Dr.-Ing. Bernhard WalkeFaculty: Electrical & Information Engineering

Aachen University (RWTH), Germany

Chair WG 4: New Radio Technologies

In: Wireless World Research Forum (WWRF)

3Bernhard Walke, Peter Sievering

Areas of Interest to contribute (1)

MESA goals: Connectivity irrespective of time and place, incl. operation in areas where

public telecommunication infrastructure has been partially destroyed or is overloaded

High level of mobility “Always best connected”

Proposed research contributions

1. Ad hoc multihop wireless broadband system design

2. Integration of broadband wireless networks into terrestrial cellular radio networks

3. Integration of broadband wireless networks into satellite systems

4Bernhard Walke, Peter Sievering

Areas of Interest to contribute (2)

4. System Comparison/Evaluation based on Tools and Scenarios ComNets has its own unique tools for system level performance

evaluation. The most important system level simulators are

GPRSim: GPRS/EDGE systems URIS: UMTS radio interface protocol simulator MOSS: Mobile satellite systems TETRIS: TETRA radio interface protocol simulator WARP2: IEEE 802.11a/b/e and HiperLAN/2 protocols W-CHAMBSim: ComNets Broadband WLAN designed for MESA

GOOSE: Combined link and system level simulator for GSM/(E)GPRS, TETRA, UMTS, WLAN

Envisaged effort: 4 man-years per year over project duration

5Bernhard Walke, Peter Sievering

System Level Simulation Environment

Protocolsformallyspecified in SDL

C++ CodeGenerator C++SDL - GR SDL - PR

PerformanceSimulation

Y

X

SDL TraceSimulator

State

Signal

Task

Start

Graphical Traceand Debug

MSC

Compile+ Link

SPEET Class Library

ADTs- Random Generator- Statistical Evaluation- Simulation Parameter- other

SDL2SPEETCL

SPEET = SDL Performance Evaluation Environment and Tools

6Bernhard Walke, Peter Sievering

Example Analysis: One Hop Scenario

Ethernet

MPEG download video stream (5 Mb/s), the packet sizes are read from the trace file.

One duplex N-ISDN connection (64 kb/s)

Eight terminals exchanging Ethernet packets in a circular way, the Ethernet packet sizes are read from the trace file. Date rates are varied to model different loads.

The transmission rates of HiperLAN/2, IEEE 802.11a and W-CHAMB are 27 Mb/s, 24Mb/s and 24Mb/s, respectively

PCF is used in IEEE 802.11a to serve the MPEG and N-ISDN services. RTS/CTS threshold of DCF is 500 bytes.

Ethernet

Ethernet

Ethernet

Ethernet

Ethernet

EthernetEthernet

N-ISDN

MPEG

Fixed corenetwork

AP

7Bernhard Walke, Peter Sievering

One Hop Traffic Performance Results

W-CHAMB is able to guarantee QoS for N-ISDN and MPEG services without a central control.

H/2 has the best traffic performance in this one hop scenario.

IEEE 802.11a can support QoS for real time traffic with its PCF that functions only in a fully connected network.

The prioritized services N-ISDN and MPEG are served completely under the all load conditions.

The maximum throughput of W-CHAMB for the Ethernet service is a little lower than that of H/2, but significantly higher than that of IEEE 802.11a.

Traffic load

0

0.1

0.2

0.3

0.4

0.5

0.6

0.2 0.4 0.6 0.8 1

EthernetMPEGISDN

Thr

ough

put

W-CHAMB

IEEE 802.11a

HiperLAN/2

1.20.001

0.01

0.1

1

0 2 4 6 8 10 12 14

ISDNMPEG

Delay [ms]

P(T

>t)

HiperLAN/2

IEEE 802.11a

W-CHAWB

8Bernhard Walke, Peter Sievering

Some Published Work on MESA Related Subjects M. Lott, B. Walke: Performance Analysis of a Wireless Ad hoc Network with

QoS Support, Telecommunication Systems, Vol. 16, 2001 B. Walke, B. Xu: A New Air Interface Concept for Wireless Multimedia

Communications beyond the 3rd Generation, In Proc. IEEE WPMC, Aalborg, Sept. 2001

B. Walke, B. Xu: On the MAC Performance of Self-organizing Broadband Multihop Multimedia Wireless, In Proc. IEEE VTC, Atlantic City, Oct. 2001

B. Walke, B. Xu: Design Issues of Self-organizing Broadband Wireless Networks, Computer Networks, Vol. 21, 2001

B. Xu, B. Walke: W-CHAMB: A Wireless Channel Oriented Ad-hoc Multihop Broadband Network - Comparison with IEEE 802.11, In Proc. European Wireless, Munich, Oct. 1999

M. Lott: Random Access for Wireless Ad hoc Broadband Networks, In Proc. European Wireless, Munich, Oct. 1999

M. Lott, B. Walke: Performance of the Wireless Ad hoc Network W-CHAMB, In Proc. European Wireless, Munich, Oct. 1999

B. Xu, B. Walke: Connection Control and Mobility Management in an Ad-hoc Wireless ATM Multihop LAN, In Proc. PIMRC'99, Osaka, Sept. 1999

M. Lott, B. Walke: Performance analysis of a Wireless Ad hoc Network with QoS Support, In Proc. SPECTS '99, Chicago, July 1999