Research On Transparent Coexistence Based On Subcarrier Identification In Heterogeneous Wireless Networks

With the rapid development and wide application of Internet of things,a variety of incompatible wireless communication protocols and diversified wireless devices usually share the 2.4G universal ISM(industrial,scientific and medical)band,resulting in multitechnology coexistence,e.g.,Wi-Fi and Zigbee compete for the same spectrum resource in the same space.The multi-technology interference caused by the coexistence of heterogeneous wireless networks will greatly degrade the system performance,which is the main challenge for wireless communication in the multi-technology coexistence environment.Different from traditional wireless communication,the coexistence of heterogeneous wireless networks is faced with highly dynamic and complicated wireless channel state.To improve the system performance of multi-technology coexistence,and achieve the “transparent coexistence” of diversified devices,it is urgent to carry out the research on fine-grained evaluation of wireless channel and effective fine-grained channel state based data transmission mechanism.Taking fine-grained channel state evaluation into account,this thesis focus on transparent coexistence of heterogeneous wireless networks,combine with the needs of the project "Research on Optimization of Transparent Coexistence Mechanism of Heterogeneous Wireless Networks [61872295]" from the National Natural Science Foundation of China,and conduct a comprehensive study on optimization of multi-technology coexistence based on subcarrier identification.The main achievements are as follows:(1)Taking different subcarrier quality caused by channel fading into consideration,this thesis first make fine-grained assessment of the channel state and classify the subcarriers according to their quality,and then propose an adaptive data transmission algorithm based on subcarrier quality.The performance of multi-technology coexistence can be enhanced when the important data type is mapped into reliable subcarriers as well as the coding rate is adjusted adaptively.The experimental results of the platform WARP and performance analysis verify that the feasibility of our proposed method.(2)To deal with the problem of low transmission success ratio caused by multi-technology interference in the coexistence environment of heterogeneous wireless networks,e.g.,coexistence of Wi-Fi devices and Zigbee devices,taking different influence of multitechnology interference sources into account,combine with subcarrier silence and rate adaptation,this thesis propose a transparent transmission algorithm based on interference source identification on top of convolutional neural network.The performance of multitechnology coexistence can be improved via interference source identification and interference grading.The experimental results of the WARP and CC2530 verify that our proposed scheme can enhance throughput,the transmission success ratio and robustness of multi-technology coexistence.