Divide-and-Conquer: Approaching the Capacity of the Two-Pair Bidirectional Gaussian Relay Network
Divide-and-Conquer: Approaching the Capacity of the Two-Pair Bidirectional Gaussian Relay Network
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DOI：
10.1109/tit.2011.2177773
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发表时间：
2010-01
影响因子：
2.5
通讯作者：
A. Sezgin;A. Avestimehr;M. Khajehnejad;B. Hassibi
中科院分区：
文献类型：
--
作者：
A. Sezgin;A. Avestimehr;M. Khajehnejad;B. Hassibi
研究了多对双向中继网络的容量域，在该网络中，一个中继节点可以方便多个用户对之间的通信。这个问题首先在线性移位确定性信道模型的背景下被研究。描述了当中继器对于任意数量的对以全双工模式或半双工模式操作时该网络的容量区域。结果表明，割集上界是紧的，容量区域是通过所谓的分而治之的中继策略获得的。然后将从确定性网络获得的洞察力用于高斯双向中继网络。确定性信道中的策略转化为在源节点的格形码和随机高斯码的特定叠加以及在高斯网络的接收节点的连续干扰抵消。分析了该方案在两个信道对下的可达速率，结果表明，对于所有的信道增益，它可以达到每个用户3比特/秒/赫兹以内的割集上界。因此，表征了每个用户3比特/秒/赫兹以内的两对双向高斯中继网络的容量区域。
The capacity region of multi-pair bidirectional relay networks, in which a relay node facilitates the communication between multiple pairs of users, is studied. This problem is first examined in the context of the linear shift deterministic channel model. The capacity region of this network when the relay is operating at either full-duplex mode or half-duplex mode for arbitrary number of pairs is characterized. It is shown that the cut-set upper-bound is tight and the capacity region is achieved by a so called divide-and-conquer relaying strategy. The insights gained from the deterministic network are then used for the Gaussian bidirectional relay network. The strategy in the deterministic channel translates to a specific superposition of lattice codes and random Gaussian codes at the source nodes and successive interference cancelation at the receiving nodes for the Gaussian network. The achievable rate of this scheme with two pairs is analyzed and it is shown that for all channel gains it achieves to within 3 bits/sec/Hz per user of the cut-set upper-bound. Hence, the capacity region of the two-pair bidirectional Gaussian relay network to within 3 bits/sec/Hz per user is characterized.