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- Sternad, Mikael, et al.
(författare)
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Resource allocation and control signaling in the WINNER flexible MAC concept
- 2008
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Ingår i: 68TH IEEE VEHICULAR TECHNOLOGY CONFERENCE, FALL 2008. - 9781424417216 ; , s. 1553-1557, s. Art. no. 4657161-
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Konferensbidrag (refereegranskat)abstract
- The EU WINNER projects have studied OFDM-based packet data systems beyond 3G that use adaptivity on all time-scales to obtain high flexibility and performance. The adaptive transmission in both downlink and uplink is scheduled and controlled at base stations and relay nodes and requires frequent transmission of control information over the downlink. The use of scheduling, adaptive modulation and coding, with fine granularity in both time and space, could potentially result in unrealistic bandwidth demands for such downlink control signaling. The present paper describes how this problem has been handled within WINNER in two cases: Frequency-adaptive transmission, which allows individual link adaptation within time-frequency resource units and non-frequency adaptive transmission, which averages over the channel variations in the frequency domain. An important tool for limiting the associated control information is to broadcast only a small essential set of control data to all user terminals, using a safe but therefore bandwidth-demanding code rate. The remaining control information is multicast to groups of users with different signal to interference and noise ratios (SINRs). The modulation and code rates of these transmissions are adjusted to the SINRs of these groups. The over-all coded data rate of the control transmission can thereby be reduced to acceptable levels.
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- Wijting, C., et al.
(författare)
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Key Technologies for IMT-Advanced Mobile Communication Systems
- 2009
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Ingår i: IEEE Wireless Communications. - 1536-1284 .- 1558-0687. ; 16:3, s. 76-85
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Tidskriftsartikel (refereegranskat)abstract
- WINNER is an ambitious research project aiming at identification, development, and assessment of key technologies for IMT-Advanced mobile communication systems. WINNER has devised an OFDMA-based system concept with excellent system-level performance for flexible deployments in a wide variety of operating conditions. The WINNER system provides a significant step forward from current 3G systems. Key innovations integrated into the system concept include flexible spectrum usage and relaying, adaptive advanced antenna schemes and pilot design, close to optimal link adaptation, hierarchical control signaling, and a highly flexible multiple access scheme. The end-to-end performance assessment results demonstrate that the WINNER concept meets the IMT-Advanced requirements.
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