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On the multiuser diversity of relay-aided downlink systems using reduced feedback
1Agency for Defense Development, Daejeon 305-600, Republic of Korea.
Thescientificworldjournal
|December 2, 2014
Summary
We developed a new scheduling method for relay-aided wireless systems. This efficient algorithm selects transmission modes and users, significantly reducing feedback needs while maintaining high data rates.
Area of Science:
- Wireless Communications
- Signal Processing
- Information Theory
Background:
- Relay-aided systems enhance wireless network coverage and capacity.
- Efficient multiuser scheduling is crucial for optimizing resource allocation in downlink systems.
Purpose of the Study:
- To introduce an efficient multiuser scheduling method for relay-aided downlink systems.
- To develop a feedback-efficient algorithm that balances performance and overhead.
Main Methods:
- Amplify-and-forward relaying protocol.
- Opportunistic selection of transmission mode (one- or two-hop) and mobile station (MS).
- Derivation of closed-form expressions for average achievable rates and asymptotic analysis.
Main Results:
- A feedback-efficient two-step multiuser scheduling algorithm is proposed.
- The algorithm achieves comparable rates to optimal methods with half the feedback.
- Analysis of average SNR conditions for exploiting multiuser diversity gain in two-hop transmission.
Conclusions:
- The proposed scheduling algorithm offers a practical solution for relay-aided systems.
- Significant reduction in feedback requirements without compromising performance.
- Effective utilization of multiuser diversity in two-hop relaying.
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