CrOss layer capacity Gain in Networks by utilizing Adaptive antenna Control - COGNAC

Project Details


The goal of this project is primarily to demonstrate
the potential capacity increase in wireless networks obtained by
providing a network controlled beamforming capability in wireless

Today, wireless terminals use (more or less)
omni-directional antennas which easily leads to severe interference
problems at the access points in dense traffic areas. This project
will use WiFi (IEEE 802.11) as the reference system considered for
a detailed case study and demonstrator development. This choice is
made due to WiFi's widespread usage, low cost, and in house
expertise on its functional behavior, concepts etc. By using
beamforming techniques in the wireless terminals, the transmitted
and received energy can be concentrated towards the relevant
access point while minimizing the unwanted energy transmitted
towards any other access point. This has the potential of several
benefits among which are (i) capacity increase in the network due
to reduced interference, and (ii) reduction of energy consumption
as the useless and disturbing energy not directed towards the
relevant access point is significantly reduced. Other benefits are
obtained which are further described in the technical project
description. The control of the beamforming is handled by the
network which makes it possible to use cross layer optimization
for high quality of service (QoS). This is expected to clearly
outperform a simpler possible technique based on only received
signal strength indication which does not necessarily give an
accurate estimate of QoS. The proposed solution is transparent to
the user and the demonstrator will be made as an extension to a
standard WiFi card. The demonstrator will clearly illustrate the
capacity gain by having two mobile terminals which without COGNAC
will cause severe interference at the two considered access
points, and high capacity with COGNAC enabled. A real time video
application is chosen due to its high data rate requirements.

The project is a joint effort of the A&P, WING and RISC divisions.
The role of RISC is to provide work on the beamforming circuitry,
assistance with
implementing the demonstrator, and overall project management.
Effective start/end date01/10/200401/09/2006