为落实国家的数字交通十四五发展规划,船舶行业的数字化转型迫在眉睫。由于集装箱船钢制结构的特性,常规物联网(The Internet of Thing,IoT)无线通信技术难以保证通信网络的稳定性和可靠性,并且在规模、网络吞吐量等方面存在限制,选取...为落实国家的数字交通十四五发展规划,船舶行业的数字化转型迫在眉睫。由于集装箱船钢制结构的特性,常规物联网(The Internet of Thing,IoT)无线通信技术难以保证通信网络的稳定性和可靠性,并且在规模、网络吞吐量等方面存在限制,选取抗干扰性强、可扩展性好和功耗低覆盖广的LoRa技术作为集装箱船无线网络的通信技术,并对LoRaWAN中的自适应数据速率(Adaptive Data Rate,ADR)算法的问题进行深入分析,解决无线网络因大规模节点部署而造成的数据碰撞、功耗高问题;使用NS-3仿真工具并调用LoRaWAN模块,实现基于ADR算法的LoRa无线网络仿真模拟;参照21000 TEU集装箱船的技术资料得到船舶场景下的网络配置参数,对LoRaWAN仿真模型进行有效修正。通过仿真测试计算,得到在3000个冷箱情况下LoRaWAN网络的数据包投递率(Packet Delivery Ratio,R_(PD))为0.85,其平均功耗为350 mJ。相比于其他控制策略,使用ADR算法的控制策略的网络性能有显著提升,证明该算法在集装箱船场景下的可靠性和稳定性,为集装箱船场景的LoRa无线网络控制策略的选择和优化提供指导。展开更多
A location-adaptive transmission scheme for indoor visible light communication(VLC) system is proposed in this paper.In this scheme,the symbol error rate(SER) of less than 10-3 should be guaranteed.And the scheme is r...A location-adaptive transmission scheme for indoor visible light communication(VLC) system is proposed in this paper.In this scheme,the symbol error rate(SER) of less than 10-3 should be guaranteed.And the scheme is realized by the variable multilevel pulse-position modulation(MPPM),where the transmitters adaptively adjust the number of time slots n in the MPPM symbol according to the position of the receiver.The purpose of our scheme is to achieve the best data rate in the indoor different locations.The results show that the location-adaptive transmission scheme based on the variable MPPM is superior in the indoor VLC system.展开更多
文摘为落实国家的数字交通十四五发展规划,船舶行业的数字化转型迫在眉睫。由于集装箱船钢制结构的特性,常规物联网(The Internet of Thing,IoT)无线通信技术难以保证通信网络的稳定性和可靠性,并且在规模、网络吞吐量等方面存在限制,选取抗干扰性强、可扩展性好和功耗低覆盖广的LoRa技术作为集装箱船无线网络的通信技术,并对LoRaWAN中的自适应数据速率(Adaptive Data Rate,ADR)算法的问题进行深入分析,解决无线网络因大规模节点部署而造成的数据碰撞、功耗高问题;使用NS-3仿真工具并调用LoRaWAN模块,实现基于ADR算法的LoRa无线网络仿真模拟;参照21000 TEU集装箱船的技术资料得到船舶场景下的网络配置参数,对LoRaWAN仿真模型进行有效修正。通过仿真测试计算,得到在3000个冷箱情况下LoRaWAN网络的数据包投递率(Packet Delivery Ratio,R_(PD))为0.85,其平均功耗为350 mJ。相比于其他控制策略,使用ADR算法的控制策略的网络性能有显著提升,证明该算法在集装箱船场景下的可靠性和稳定性,为集装箱船场景的LoRa无线网络控制策略的选择和优化提供指导。
基金supported by the Jinlin Provincial Science&Tenchology Department of China(No.20130413052GH)
文摘A location-adaptive transmission scheme for indoor visible light communication(VLC) system is proposed in this paper.In this scheme,the symbol error rate(SER) of less than 10-3 should be guaranteed.And the scheme is realized by the variable multilevel pulse-position modulation(MPPM),where the transmitters adaptively adjust the number of time slots n in the MPPM symbol according to the position of the receiver.The purpose of our scheme is to achieve the best data rate in the indoor different locations.The results show that the location-adaptive transmission scheme based on the variable MPPM is superior in the indoor VLC system.