In this article, a classified system with a relay is investigated in wireless body area networks (WBANs), where some on-body sensors are divided into several sensor groups on the basis of different body parts. Not only can the network detect basic vital signs but also the physiological signals of special diseases. All groups of sensors and the relay harvest energy by the radio-frequency (RF) source broadcasting, then the same group of sensors simultaneously sends common information through cooperation to the source. Since the classified system is a confined system, we maximize the system throughput with a joint power allocation on maximum ratio combining (JPA-MRC) protocol, where the transmission power allocation at the relay is unequal for each relaying subslot. The optimal problem is solved by the Lagrange multiplier method and the Karush-Kuhn-Tucker (KKT) optimal conditions. To further the obtain optimal solution, we simplify co-optimization of relay power and sensor power to the optimization of single power by the equivalent channel gains. Analytical and simulation results show that our proposed optimal method can greatly improve the information throughput compared to the conventional mean power allocation method. In addition, the protocol based on the classified scheme outperforms than that of the conventional unclassified scheme. The impacts of various important system parameters are analyzed, which provide useful design insights under different cases.

中文翻译：

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具有无线信息和功率传输的分类 WBAN 中的联合功率分配


在本文中，研究了无线体域网（WBAN）中带有中继的分类系统，其中一些体上传感器根据不同的身体部位分为多个传感器组。网络不仅可以检测基本生命体征，还可以检测特殊疾病的生理信号。所有组的传感器和继电器通过射频源广播收集能量，然后同一组传感器通过协作同时向源发送公共信息。由于分类系统是一个受限系统，我们通过最大比组合联合功率分配（JPA-MRC）协议来最大化系统吞吐量，其中中继处的传输功率分配对于每个中继子时隙是不相等的。通过拉格朗日乘子法和Karush-Kuhn-Tucker (KKT)最优条件求解最优问题。为了进一步获得最优解，我们将中继功率和传感器功率的协同优化简化为通过等效信道增益来优化单个功率。分析和仿真结果表明，与传统的平均功率分配方法相比，我们提出的优化方法可以极大地提高信息吞吐量。此外，基于分类方案的协议优于传统的非分类方案。分析了各种重要系统参数的影响，为不同情况下的设计提供了有用的见解。