On the Performance Gain of Hybrid Decode-Amplify-Forward Cooperative Communications
On the Performance Gain of Hybrid Decode-Amplify-Forward Cooperative Communications
复制标题
DOI：
10.1155/2009/479463
复制
发表时间：
2009
影响因子：
2.6
通讯作者：
T. Duong;H. Zepernick
中科院分区：
文献类型：
--
作者：
T. Duong;H. Zepernick
我们研究了自适应解码转发 (ADF)、放大转发 (AF) 和混合解码放大转发 (HDAF) 中继协议的性能。具体来说，我们推导了这三种中继协议的符号错误概率（SEP）的封闭式表达式。对于 AF 协议，我们得出了比之前发表的工作更简单、更容易处理的最终结果。此外，通过分析高信噪比 (SNR) 状态，我们推导出 SEP 的渐近紧逼近。该近似用于评估三种不同中继协议之间的一个重要方面，即 HADF 相对于两种传统中继方案 ADF 和 AF 的 SEP 性能增益。结果表明，HDAF 相对于 ADF 和 AF 的性能增益很大程度上取决于源到中继和中继到目的地链路之间的信道条件的相对值。有趣的是，如果中继靠近源，则 HDAF 与其他两种方法相比没有任何优势。相比之下，当中继移动到目的地附近时，HDAF 相对于 ADF 和 AF 方案的性能提升非常大。具体来说，给出的数值结果以及我们的分析表明，对于 QPSK 调制，HDAF 的性能优于 ADF 和 AF，性能分别提高了 5 dB 和 6 dB。
We investigate the performance of adaptive decode-forward (ADF), amplify-forward (AF), and hybrid decode-amplify-forward (HDAF) relaying protocol. Specifically, we derive the closed-form expression of symbol error probability (SEP) for these three relaying protocols. For the AF protocol, we derive a simpler and more tractable final result than previously published work. Furthermore, analyzing the high signal-to-noise ratio (SNR) regime, we derive an asymptotically tight approximation for SEP. The approximation is used to assess an important aspect between the three different relaying protocols, i.e., the SEP performance gain of HADF over the two conventional relaying schemes ADF and AF. It is shown that the performance gain of HDAF over ADF and AF significantly depends on the relative value of channel conditions between source-to-relay and relay-to-destination links. Interestingly, it is shown that HDAF has no benefit compare to the two others if the relay is located close to the source. In contrast, the performance gains of HDAF over the ADF and AF scheme are remarkably large as the relay moves nearby the destination. Specifically, the numerical results given as well as our analysis indicate that for QPSK modulation, HDAF outperforms ADF and AF with a performance improvement by 5 dB and 6 dB, respectively.