Holger Degenhardt

Dipl.-Ing. Holger Degenhardt

Technische Universität Darmstadt

Fachbereich Etit

Fachgebiet Kommunikationstechnik

Merckstr.25, 64283 Darmstadt, Germany

FG Kommunikationstechnik

+49 (0)6151 16 3669

+49 (0)6151 16 4936

Forschung:

Multi-antenna two-way relaying for wireless mesh networks

The performance and coverage of wireless networks can be improved applying a relay station between source and destination. For that purpose, two-way relaying is a promising transmission scheme.

First, one single source-destination pair shall be considered which communicates applying the two-way relaying scheme. Here, it shall be investigated how to allocate the transmit power and how to adjust the beamforming weights at each node assuming asymmetric rate constraints. One possible optimization criterion is the minimisation of the transmit power.

For sensor networks, ad-hoc scenarios with multiple source-destination pairs which bidirectionally communicate with each other via a relay station are of special interest. Here, not only a pair-wise communication between one source and one destination shall be considered, but also the communication between one source and several destinations. At this, access schemes and protocols have to be developed which also consider a possible cooperation between the sources and the destinations. For each source-destination pair, beamforming and power allocation schemes have to be developed in order to fulfill the data rate requirements of the different nodes.

For the first two work packages, it is assumed that perfect channel knowledge is available. However, in a realistic scenario, perfect channel knowledge is only possible with a considerable amount of signalling overhead. Thus, the impact of imperfect channel knowledge at the different nodes on the performance of the relay network shall be investigated.