Approaching Throughput Optimality With Limited Feedback in Multichannel Wireless Downlink Networks
Approaching Throughput Optimality With Limited Feedback in Multichannel Wireless Downlink Networks
复制标题
在多通道无线下行链路网络中通过有限反馈实现吞吐量最优
DOI：
10.1109/tnet.2012.2235459
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Lei Ying
中科院分区：
文献类型：
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作者：
Ouyang Ming;Lei Ying
本文研究了频分双工（FDD）多通道无线系统下行链路反馈资源的分配问题。我们考虑一个具有单个基站、L个共享信道和N个移动用户的下行网络。像MaxWeight这样的吞吐量优化算法通常需要完整的通道状态信息（CSI） （NL链路状态）来进行调度。然而，在用户数量很大的多通道网络中，获取完整的CSI是一项令人望而却步的开销。在本文中，我们考虑了基站只分配有限数量的上行链路资源来获取信道状态信息的场景。我们首先表明，为了支持全吞吐量区域（具有完整CSI的吞吐量区域）的（1-ε）分数，基站需要在每个时隙获取至少Θ（(1-ε)L）链路状态。然后，我们提出了一种基于权重的反馈分配，称为WBF，并表明WBF与MaxWeight调度一起通过获取每个时隙Θ（L log[1/(ε)]）链路状态来实现全吞吐量区域的（1-ε）分数。对于i.i.d开关通道，我们进一步证明了Θ（Llog[1/(ε)]）每个时隙的链路状态对于实现全吞吐量区域的（1-ε）分数是必要的。
This paper studies the allocation of feedback resources in the downlink of a frequency-division duplex (FDD) multichannel wireless system. We consider a downlink network with a single base station, L shared channels, and N mobile users. Throughput optimal algorithms like MaxWeight in general require the complete channel-state information (CSI) ( NL link states) for scheduling. Acquiring the complete CSI, however, is a prohibitive overhead in multichannel networks when the number of users is large. In this paper, we consider the scenario where the base station allocates only a limited amount of uplink resources for acquiring channel-state information. We first show that to support a (1-ε) fraction of the full throughput region (the throughput region with the complete CSI), the base station needs to acquire at least Θ((1-ε)L) link states at each time-slot. We then propose a Weight-Based Feedback allocation, named WBF, and show that WBF together with MaxWeight scheduling achieves a (1-ε) fraction of the full throughput region by acquiring Θ(L log[1/(ε)]) link states per time-slot. For i.i.d. on-off channels, we further prove that Θ(Llog[1/(ε)]) link states per time-slot is necessary for achieving a (1-ε) fraction of the full throughput region.