【作者】 李阳；

【导师】 尹小燕；

【作者基本信息】 西北大学 ， 工程硕士（专业学位）， 2022， 硕士

【摘要】 随着物联网的快速发展与广泛应用,多类不兼容的无线通信协议和多元化无线通信设备共享世界通用的2.4G ISM(Industrial,Scientific and Medical)频段,致使Wi-Fi、Zig Bee等异构无线网络共存于同一空间。由于异构设备共存而导致的跨协议干扰问题,将会大幅度降低系统性能。这是多协议共存环境中数据传输要解决的难题之一。不同于传统无线通信,异构无线网络共存环境对应高度动态、高复杂度的无线信道状态。为了提高异构无线网络的整体性能,实现多元化设备的“透明共存”,亟需开展面向无线信道的细粒度评估及基于细粒度信道状态的数据传输机制研究。本文以异构无线网络的透明共存为目标,细粒度信道状态感知为切入点,结合国家自然科学基金面上项目“异构无线网络透明共存机制优化方法研究【61872295】”的相关需求,基于子载波识别,针对异构无线网络的性能优化问题展开了深入探索,主要工作包括:(1)鉴于因信道衰落等导致的子载波质量差异,本文首先对信道状态进行了细粒度感知,并对子载波按质量分级,继而提出了一种基于子载波质量的自适应数据传输方法,实现重要数据、非重要数据与强、弱子载波之间的映射,并对编码速率进行自适应调整,提高了频谱资源的利用效率与系统吞吐量。WARP研究平台的实验结果与Matlab的性能分析证实所提方法可提高系统性能。(2)针对异构无线网络场景中多元化设备间存在跨协议干扰而导致的低数据传输成功率问题,以Wi-Fi设备与Zig Bee共存环境为例,鉴于异质跨协议干扰源对无线通信的不同影响,基于卷积神经网络,结合子载波静默和速率自适应,提出了一种基于干扰源识别的透明传输方法,从子载波层面对干扰源进行细粒度识别,并对干扰进行分级,可有效提高异构无线网络的系统性能。WARP平台和CC2530节点的实验结果与性能分析证实所提方法可改善Wi-Fi和Zig Bee共存的异构无线网络的系统性能。更多还原

【Abstract】 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.更多还原