In this thesis we investigate MIMO techniques for relay channels. We first concentrate on the single antenna relay networks, where each node is equipped with a single antenna. In this scenario, a scheme called cooperative diversity has been discussed widely, where multiple relays are united in the network as a “virtual antenna array”, to mimic a MIMO system. We propose a novel cooperative diversity scheme that can improve the spectral efficiency of the network, especially for high signal to noise ratios (SNR). We analyze the capacity bounds for such schemes and also describe a signalling method to approach this capacity bound. <br> We then move to the multi-antenna node scenario, where each node is equipped with multiple antennas. We propose different signalling methods and routing protocols for MIMO relay channels and use capacity as a performance metric to evaluate and compare them. The proposed signalling methods can be applied together with the proposed routing schemes. Incorporating them can facilitate the cross-layer design. Finally, we discuss a network scenario where some nodes are equipped with multiple antennas, others are equipped with single antennas. We constrain ourselves to the case where the source and destination are equipped with a single antenna. We characterize the capacity performance and the diversity-multiplexing tradeoff of such a network. We show that relaying can offer a significant performance advantage over non-relay transmission in certain scenarios, by applying signal combining techniques for the point-to-point MIMO link into relay channels.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:650479 |
| Date | January 2006 |
| Creators | Fan, Yijia |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/10884 |
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