Publica
Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Optimal Transmit Strategies in MultiAntenna Bidirectional Relaying
 Institute of Electrical and Electronics Engineers IEEE: IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP 2007. Proceedings. Vol.3 : Honolulu, 15  20 April 2007 Piscataway/NJ: IEEE, 2007 ISBN: 1424407273 
 International Conference on Acoustics, Speech, and Signal Processing (ICASSP) <2007, Honolulu> 

 English 
 Conference Paper 
 Fraunhofer HHI () 
Abstract
We study the transmit strategies in a MIMO bidirectional relaying scenario with individual power constraints. In two phases a halfduplex relay node decodesandforwards the signals of two nodes. Each node has multiple antennas. We deduce the transmit strategy in the first phase from the general Gaussian MIMOMAC. Since each node knows a priori the interference of its own message in the second phase interferencefree reception is achieved. Therefore, the optimal relay transmit strategy is given by two pointtopoint waterfilling solutions which are coupled by the relay power distribution. In the large SNR, the sum of any bidirectional rate tuple on the boundary of the rate region is asymptotically proportional with the minimum spatial degree of both MIMO channels.