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- Alexandropoulos, G. C., et al.
(author)
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A Comparative Study of Relaying Schemes with Decode and Forward over Nakagami-m Fading Channels
- 2011
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In: Journal of Computer Networks and Communications. - : Hindawi Limited. - 2090-715X .- 2090-7141. ; 2011
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Journal article (peer-reviewed)abstract
- Although relaying can be very beneficial for wireless systems, understanding which relaying schemes can achieve specific performance objectives under realistic fading is crucial. In this paper we present a general framework for modeling and evaluating the performance of dual-hop decode-and-forward (DF) relaying schemes over independent and not necessarily identically distributed (INID) Nakagami-m fading channels. We obtain closed-form expressions for the statistics of the instantaneous output signal-to-noise ratio of repetitive transmission with selection diversity. Furthermore, we present a unified statistical overview of other three significant relaying schemes with DF, one based on repetitive transmission with maximal-ratio diversity and the other two based on relay selection (RS). To compare the considered schemes, we present closed-form and analytical expressions for the outage probability and the average symbol error probability under various modulation methods, respectively. Importantly, it is shown that when the channel state information for RS is perfect, RS-based schemes always outperform repetitive ones. Furthermore, when the direct link between the source and the destination nodes is sufficiently strong, relaying may not result in any gains, and it should be switched off.
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| 2. |
- Marinchenko, Oleg, et al.
(author)
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BuNGee project overview
- 2011
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In: IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems (COMCAS 2011). - 9781457716928
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Conference paper (peer-reviewed)abstract
- The BuNGee FP7 project is looking at achieving throughput densities substantially higher than available with today‘s systems. The project addresses this goal by a combination of techniques: below-rooftop access base stations and a unique feeding architecture using a combination of licensed in-band and out-of-band license exempt spectrum. Very high capacity feeding hubs with high-order spatial reuse are created using multi-beam antennas and advanced MIMO techniques, using millimeter waves.
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| 3. |
- Papadogiannis, Agisilaos, 1982, et al.
(author)
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Efficient Interference Mitigating Strategies for Two-Way Relay Channels
- 2011
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In: Proceedings of the International Symposium on Wireless Communication Systems. - 2154-0217 .- 2154-0225. - 9781612844022 ; , s. 680-684
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Conference paper (peer-reviewed)abstract
- Hierarchical wireless networks have the potential to provide the needed capacity to a large number of mobile stations (MSs). According to this system architecture, the MSs are served by a dense network of fixed relay nodes (RNs) fed by a small number of large hub base stations (HBSs). In such deployment, high spectral efficiencies can be achieved if the RNs act as two-way relays; however this gives rise to co-channel interference (CCI) which needs to be mitigated. In order to gain insights on the impact of CCI to this scenario we consider an HBS with two highly directional antennas communicating with two MSs via two interfering two-way RNs. We investigate the average maximum sum-rate of two cooperative strategies. The first is based on Decode-and-Forward (DF) and network coding and acts as a baseline. The second strategy is based on Amplify-and-Forward (AF) and Network MIMO processing over both the backhaul and access channels. Furthermore we devise some cooperative protocols that utilize two, three or four time slots. It is shown that the 2-slot schemes perform generally better and that the DF strategy achieves superior performance when CCI is low while AF with Network MIMO is superior when CCI is high.
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