Machine type communication connecting machines in the Internet of Things (IoT) brings massive traffic and rapidly increases the demand for radio spectrum in wireless networks. To transmit the traffic in limited spectra, a time division multiple access (TDMA) based interface with a reservation scheme, which is spectrum-efficient, energy-efficient, and deployment-economical, was proposed in cognitive radio based machine type communication. Since radio frequency (RF) energy harvesting is a way to charge stand-alone or low-power machines in IoT and full-duplex communication potentially doubles spectral efficiency, this paper proposes a multiple access control that incorporates RF energy harvesting and full-duplex communication into the TDMA based interface with a reservation scheme. The proposed multiple access control elaborately uses the full-duplex functionality with a mechanism of detecting primary users to appropriately turn on/off RF charging such that the trade-off between the interference of primary users and RF charging is balanced. Extensive simulation results show that the proposed multiple access control produces high system throughput while the interference of primary users is kept at a low level.

物联网（IoT）中的机器类型通信连接机器带来了大量流量，并迅速增加了无线网络对无线电频谱的需求。为了在有限的频谱中传输业务，在基于认知无线电的机器类型通信中提出了一种基于时分多址（TDMA）的接口，该接口带有预留方案，具有频谱高效，节能和部署经济的优点。由于射频（RF）能量收集是一种为IoT中的独立或低功率机器充电的方式，并且全双工通信可能使频谱效率翻倍，因此本文提出了一种将RF能量收集和全双工通信相结合的多路访问控制使用预留方案进入基于TDMA的接口。所提出的多路访问控制精心地使用全双工功能以及检测主要用户的机制，以适当地开启/关闭RF充电，从而平衡了主要用户的干扰与RF充电之间的权衡。大量的仿真结果表明，所提出的多路访问控制产生了较高的系统吞吐量，同时主要用户的干扰保持在较低水平。