Objectives:

• Bidirectional relaying
• Physical layer network coding
• Implementation of bidirectional relaying using real-time hardware

Work Tasks (currently):

• Design and optimization of two-way relaying systems
• Investigation of implementation aspects

Detailed description:

Cooperative communication is a very promising candidate to realize enhanced system performance, reliability, and coverage extension for wireless systems. Supporting the transmission between two nodes by intermediate relay stations reduces the effective path loss but also limits spectral efficiency due to the half-duplex constraint. To combat this drawback bidirectional relaying systems exploiting the broadcast nature of the wireless link and the principle of network coding can be applied. In order to exchange information with each other the two participating source nodes transmit their messages simultaneously to the relay and the relay then transmits a joint message to both nodes, which can finally estimate the contrary message using the information transmitted previously. The most challenging task in this context is the construction of the relay message based on the disturbed receive signal given by the superposition of both source messages. Within this project, we aim to improve the system performance by the application of multiple-antenna relays or distributed relaying concepts. New approaches for joint channel decoding and physical layer network coding will be designed for both concepts and techniques to exploit cooperation between distributed relays will be developed. A major focus lies on implementation aspects in the physical layer like synchronization, channel estimation for distributed nodes as well as detection and decoding algorithms. In order to confirm these theoretical investigations, a selection of bidirectional relaying approaches will be implemented using real-time hardware platforms. Thus, the gains in theory and practice can be compared taking the implementation complexity into account.

This project is funded within the DFG-Schwerpunktprogramm 1397 COIN (Communication in Interference Limited Networks).

Details