摘要
现有井下无线信道建模主要针对巷道、井筒和房柱等几何结构相对规则的特定场景,对于几何形状复杂多变、介质分布不均匀的采空区场景适用性不足。针对煤矿采空区多孔非均匀介质环境,采用弹跳射线法进行无线信道建模。首先,建立煤矿采空区环境模型,通过弹跳射线法对电磁波在采空区多孔非均匀介质中的传播机制进行仿真,获取发射机−接收机、发射机−中继器、中继器−接收机之间的直射路径和反射路径。然后,针对各条传播路径,引入反射系数建立信道冲激响应模型和路径损耗模型,并综合考虑采空区环境温度和设备噪声系数,构建热噪声模型。最后,通过对多径分量进行相干矢量叠加,生成复合接收信号。基于所建立的采空区多孔非均匀介质无线信道模型,对0.7,0.8,0.9,2.6,3.5,5.9 GHz频率下的信噪比进行了仿真,得到信噪比与频率呈显著负相关关系,这与煤矿井下无线通信的理论规律相符,表明所建立的无线信道模型能准确反映不同频率电磁波在采空区环境中的传播特性差异;在模拟采空区环境下,采用ZigBee和LoRa通信模块开展了2.4 GHz,868 MHz和915 MHz频率下不同传输距离的接收信号强度测试,测试结果与仿真结果具有良好的一致性,验证了所建立无线信道模型的准确性。
Existing underground wireless channel modeling mainly focuses on specific scenarios with relatively regular geometric structures such as roadways,shafts,and room-and-pillar structures,which is insufficient for goaf scenarios with complex and variable geometric shapes and non-uniform media distribution.For the porous heterogeneous media environment of coal mine goaf,the bouncing ray method is adopted to establish the wireless channel model.First,a coal mine goaf environment model was established,and the bouncing ray method was used to simulate the propagation mechanism of electromagnetic waves in the porous heterogeneous media of the goaf.Direct and reflected paths between transmitter-receiver,transmitter-repeater,and repeater-receiver were obtained.Then,for each propagation path,reflection coefficients were introduced to establish the channel impulse response model and the path loss model,and a thermal noise model was constructed by comprehensively considering the goaf environment temperature and the equipment noise coefficient.Finally,through coherent vector superposition of multipath components,the composite received signal was generated.Based on the established porous heterogeneous media wireless channel model of the goaf,the signal-to-noise ratios at frequencies of 0.7,0.8,0.9,2.6,3.5,and 5.9 GHz were simulated.The results showed that SNR was significantly negatively correlated with frequency,which was consistent with the theoretical principle of underground coal mine wireless communication,indicating that the established wireless channel model accurately reflected the propagation characteristics of electromagnetic waves at different frequencies in the goaf environment.In addition,under the simulated goaf environment,ZigBee and LoRa communication modules were used to conduct received signal strength tests at frequencies of 2.4 GHz,868 MHz,and 915 MHz with different transmission distances.The test results showed good consistency with the simulation results,verifying the accuracy of the established wireless channel model.
作者
王洪梅
李含笑
卢旭
孟庆勇
沈胜强
李世银
WANG Hongmei;LI Hanxiao;LU Xu;MENG Qingyong;SHEN Shengqiang;LI Shiyin(School of Information and Control Engineering,China University of Mining and Technology,Xuzhou 221116,China;State Key Laboratory of Intelligent Coal Mining and Strata Control,Beijing 100013,China;China Coal Research Institute,Beijing 100013,China)
出处
《工矿自动化》
北大核心
2025年第8期67-73,87,共8页
Journal of Mine Automation
基金
江苏省研究生科研与实践创新计划项目(KYCX25_2985)
中国矿业大学研究生创新计划项目(2025WLJCRCZL112)
国家自然科学基金面上项目(62371451)
煤炭智能开采与岩层控制全国重点实验室开放基金项目(SKLIS202406)
江苏省自然科学基金面上项目(BK20242083)。
关键词
煤矿采空区
多孔非均匀介质
无线信道建模
弹跳射线法
电磁波传播
多径效应
coal mine goaf
porous heterogeneous media
wireless channel modeling
bouncing ray method
electromagnetic wave propagation
multipath effect
