Bluetooth low energy(BLE)-based indoor localization has been extensively researched due to its cost-effectiveness,low power consumption,and ubiquity.Despite these advantages,the variability of received signal strength...Bluetooth low energy(BLE)-based indoor localization has been extensively researched due to its cost-effectiveness,low power consumption,and ubiquity.Despite these advantages,the variability of received signal strength indicator(RSSI)measurements,influenced by physical obstacles,human presence,and electronic interference,poses a significant challenge to accurate localization.In this work,we present an optimised method to enhance indoor localization accuracy by utilising multiple BLE beacons in a radio frequency(RF)-dense modern building environment.Through a proof-of-concept study,we demonstrate that using three BLE beacons reduces localization error from a worst-case distance of 9.09-2.94 m,whereas additional beacons offer minimal incremental benefit in such settings.Furthermore,our framework for BLE-based localization,implemented on an edge network of Raspberry Pies,has been released under an open-source license,enabling broader application and further research.展开更多
Bluetooth技术可实现短距离、低功耗的无线通信和构成无线网络(Piconet and Scatternet),采用Bluetooth技术构建的数据采集无线网络系统(Data Acquisition Wireless Network System based on Bluetooth:DAWNS-B)便于进行集中测量和控制...Bluetooth技术可实现短距离、低功耗的无线通信和构成无线网络(Piconet and Scatternet),采用Bluetooth技术构建的数据采集无线网络系统(Data Acquisition Wireless Network System based on Bluetooth:DAWNS-B)便于进行集中测量和控制。介绍Bluetooth ASIC的结构特性以及DAWNS—B的结构原理、硬件电路接口和软件系统。DAWNS-B由前、后端单元构成,Bluetooth ASIC的HCI与PC计算机(或单片机)接口,Bluetooth协议软件栈控制Bluetooth ASIC对主机的HCI命令以及前、后端无线通信和网络通信,应用程序实现数据采集、处理DAWNS-B实现测控系统移动数据交换和无线网络功能,扩大和增强了数据采集系统的功能和应用场合。展开更多
2016年7月31日广西苍梧发生的MS5.4地震是广西测震台网自建立以来所记录到的区域内最强地震。不同机构对于此次事件给出的震源深度结果相差较大,例如美国地质调查局(USGS)地震目录显示其深度为24.5km,而全球矩心矩张量研究中心(Global C...2016年7月31日广西苍梧发生的MS5.4地震是广西测震台网自建立以来所记录到的区域内最强地震。不同机构对于此次事件给出的震源深度结果相差较大,例如美国地质调查局(USGS)地震目录显示其深度为24.5km,而全球矩心矩张量研究中心(Global CMT)测定的深度为15.6km。为了进一步准确确定广西苍梧地震的震源深度,文中基于区域速度模型,首先利用走时残差全局搜索法初步得到此次地震震源深度及误差范围,然后使用CAP(Cut and Paste)方法反演苍梧地震震源机制,在此基础上,采用Rayleigh波振幅谱和sPL震相方法进一步约束了此次地震的震源深度。研究结果显示:利用走时残差全局搜索法获得的苍梧MS5.4地震震源深度及误差范围为(13±3)km,CAP方法反演的深度为10km,Rayleigh波振幅谱测定深度结果为9~10km,sPL震相测定深度结果为10km,最终确定广西苍梧MS5.4地震的震源深度约10km,这表明此次事件仍为发生于上地壳的地震。本文结果同时表明,USGS地震目录在研究区的震源深度精度有待提高。展开更多
基金supported by James M.Cox Foundation,National Institute on Deafness and Other Communication Disorders(grant no.1R21DC021029-01A1)Cox Enterprises Inc.,National Institute of Child Health and Human Development(grant no.AWD-006196-G1)Thrasher Research Fund Early Career Award Program.
文摘Bluetooth low energy(BLE)-based indoor localization has been extensively researched due to its cost-effectiveness,low power consumption,and ubiquity.Despite these advantages,the variability of received signal strength indicator(RSSI)measurements,influenced by physical obstacles,human presence,and electronic interference,poses a significant challenge to accurate localization.In this work,we present an optimised method to enhance indoor localization accuracy by utilising multiple BLE beacons in a radio frequency(RF)-dense modern building environment.Through a proof-of-concept study,we demonstrate that using three BLE beacons reduces localization error from a worst-case distance of 9.09-2.94 m,whereas additional beacons offer minimal incremental benefit in such settings.Furthermore,our framework for BLE-based localization,implemented on an edge network of Raspberry Pies,has been released under an open-source license,enabling broader application and further research.
文摘Bluetooth技术可实现短距离、低功耗的无线通信和构成无线网络(Piconet and Scatternet),采用Bluetooth技术构建的数据采集无线网络系统(Data Acquisition Wireless Network System based on Bluetooth:DAWNS-B)便于进行集中测量和控制。介绍Bluetooth ASIC的结构特性以及DAWNS—B的结构原理、硬件电路接口和软件系统。DAWNS-B由前、后端单元构成,Bluetooth ASIC的HCI与PC计算机(或单片机)接口,Bluetooth协议软件栈控制Bluetooth ASIC对主机的HCI命令以及前、后端无线通信和网络通信,应用程序实现数据采集、处理DAWNS-B实现测控系统移动数据交换和无线网络功能,扩大和增强了数据采集系统的功能和应用场合。
文摘2016年7月31日广西苍梧发生的MS5.4地震是广西测震台网自建立以来所记录到的区域内最强地震。不同机构对于此次事件给出的震源深度结果相差较大,例如美国地质调查局(USGS)地震目录显示其深度为24.5km,而全球矩心矩张量研究中心(Global CMT)测定的深度为15.6km。为了进一步准确确定广西苍梧地震的震源深度,文中基于区域速度模型,首先利用走时残差全局搜索法初步得到此次地震震源深度及误差范围,然后使用CAP(Cut and Paste)方法反演苍梧地震震源机制,在此基础上,采用Rayleigh波振幅谱和sPL震相方法进一步约束了此次地震的震源深度。研究结果显示:利用走时残差全局搜索法获得的苍梧MS5.4地震震源深度及误差范围为(13±3)km,CAP方法反演的深度为10km,Rayleigh波振幅谱测定深度结果为9~10km,sPL震相测定深度结果为10km,最终确定广西苍梧MS5.4地震的震源深度约10km,这表明此次事件仍为发生于上地壳的地震。本文结果同时表明,USGS地震目录在研究区的震源深度精度有待提高。