Maximizing Expected Achievable Rates for Block-Fading Buffer-Aided Relay Channels
Maximizing Expected Achievable Rates for Block-Fading Buffer-Aided Relay Channels
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DOI：
10.1109/twc.2016.2572690
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发表时间：
2016-09
影响因子：
10.4
通讯作者：
M. Shaqfeh;Ammar Zafar;H. Alnuweiri;Mohamed-Slim Alouini
中科院分区：
文献类型：
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作者：
M. Shaqfeh;Ammar Zafar;H. Alnuweiri;Mohamed-Slim Alouini
在本文中，使用结合三种基本传输策略的混合方案，即解码转发、压缩转发和直接传输，最大限度地提高了块衰落缓冲辅助中继信道的长期平均可达速率。该混合方案基于信道状态信息进行动态调整。这三种策略的整合和优化提供了一个更通用和基本的解决方案，并给出了比文献中已知的方案更好的可实现率。尽管优化变量较多，但所提出的混合方案可以使用简单的封闭公式进行优化，易于在实际继电器系统中应用。这包括在基于信道条件选择压缩转发策略时调整传输速率和压缩。此外，根据中继是半双工还是全双工，以及源和中继是正交还是非正交信道接入，本文将混合方案应用于高斯块衰落缓冲辅助中继信道的三种不同模型。给出了几个数值例子来证明可实现的速率结果，并将它们与所考虑的三种通道模型中的每一种遍历容量的上界进行了比较。
In this paper, the long-term average achievable rate over block-fading buffer-aided relay channels is maximized using a hybrid scheme that combines three essential transmission strategies, which are decode-and-forward, compress-and-forward, and direct transmission. The proposed hybrid scheme is dynamically adapted based on the channel state information. The integration and optimization of these three strategies provide a more generic and fundamental solution and give better achievable rates than the known schemes in the literature. Despite the large number of optimization variables, the proposed hybrid scheme can be optimized using simple closed-form formulas that are easy to apply in practical relay systems. This includes adjusting the transmission rate and compression when compress-and-forward is the selected strategy based on the channel conditions. Furthermore, in this paper, the hybrid scheme is applied to three different models of the Gaussian block-fading buffer-aided relay channels, depending on whether the relay is half or full duplex and whether the source and the relay have orthogonal or non-orthogonal channel access. Several numerical examples are provided to demonstrate the achievable rate results and compare them to the upper bounds of the ergodic capacity for each one of the three channel models under consideration.