Research activity for year 2005

Summary of research activity for year 2004

• During the academic years 2005 - 2006 we plan to continue our research in the field of OFDM/OFDMA wireless systems. The results of the development projects of year 2004 were basic models for a base station (BS) and user  station. Multiple user station may communicate with the basestation using a detailed signalling mechanism that follows the IEEE802.16 standard. In addition a simple scheduler (DRR) was implemented. In a separate research project (Itzik Kitroser) we developed a detailed set of scheduling algorithms that solve the problem of 2D scheduling for OFDMA systems under several sets of constraints (priority, waiting time, power, required bandwidth etc.). The performance of these algorithms were tested with a Matlab and C/C++ stand alone simulation with a synthetic 4IPP traffic source.

Research plan for year 2005

Network conditions

• We plan to implement part of the scheduling algorithms developed last year and investigate their performance under carefully controlled network activity that include various traffic sources and applications.  OPNET will serve as the main tool for this research. We intend to test the abilitie of several schedulers for QoS requirements for voice, multimedia and data applications.

Mobility

• On going standartization activity attempts to extend the IEEE802.16 standard to support mobile users. We are planning to develope several mechanisms to support mobility and upgrade the OPNET BS node model to support mobility. We will focus on handover support for multi-sector multi-cell wireless systems. We will also investigate the inter-relations with mobile IP and other issues of mobile IP users.

The LSRT Project - 2004

This year we continue our work in the LSRT project.
We plan to accomplish the followings:

1.   Efficient scheduling algorithms for IEEE802.16 OFDMA standard

The ne.w emerging IEEE 802.16 standard introduce new intersting scheduling
problems. The combination of multi-rate multiple channels and the OFDMA
protocols needs an efficient resource allocation mechanism. Last year we implemented
two building blocks for this protocol: A base station operating
with this protocol and an end station which is connected with a single base
station )due to the fixed acces topology(. In parallel we investigated new
scheduling policies that will be implemented this year later in the
base station OPNET model. The development of the scheduling solutions involved the
4IPP traffic model that was suggested by the IEEE802.16 committee. with OPNET we
"expect to test the scheduling algorithm more accurately by using more "realistic
.traffic models including mixed of TCP and UDP sessions

2.  Integration and simulation of LSRT networks

OPNET supports automatic network generation for practical usage. For the academic
world, ideas must be tested over many network tooplogies with various scales and
properties. Last year we developed a VB tools that generates XML files describing
OPNET LSRT networks.During this process we recognized that the EMA mechanism is far
from being efficient or easy, especially for automatic generation of networks. The
XML approach is much more intuitive and easy. However, READING XML files into OPNET
.(is a very slow process. In assition it is manual )at least with the modeler tool
We are using our tool to read external definitions of basestation positions, load a
map into OPNET project, and put network equipment in predefined locations. We are
also to configure automatically several Configuration modules. At the end of this
year we hope to have simulation results of various LSRT networks that were generated
.with our tool