Design And Implementation Of Medium Access Control Protocol For Electric Broadband Internet Of Things

With the rapid growth of diverse interactive demands for intelligent electric operation and maintenance,only considering the transmission of numerical sensing services can no longer meet the requirements for on-site use.The electric broadband Internet of Things needs to break through the bandwidth capacity constraints of narrowband wireless sensor network technologies such as LoRa and Zigbee;and adapt to the needs of typical electric service transmission such as partial discharge monitoring maps and inspection images.Therefore,in order to meet the requirement from electric scenarios to the bandwidth,capacity and energy consumption of the sensor network,it is urgent to research the MAC layer protocol suitable for the electric broadband Internet of Things based on the existing wireless technology.According to the scene characteristics of a typical 500kV transmission line or a substation,this thesis studies the MAC layer protocol which is suitable for the electric broadband Internet of Things,and mainly does the following work.(1)Aiming at the communication and business requirements of typical electric scenarios,the core communication parameters requirements such as communication rate,electric consumption,and topology are analyzed,and the networking architecture of electric transmission and transformation scenarios is designed;The analytic hierarchy process is used to compare and select various traditional broadband wireless communication technologies,and IEEE 802.11n is selected as the basis for protocol design and implementation.(2)Aiming at the serious collision and high electric consumption in electric application scenarios by IEEE 802.11n,a hybrid MAC layer protocol based on superframe structure is designed,and the simulation results show that this protocol can reduce the collision probability by about 30%compared with the standard protocol,and it also reduces the sensor electric consumption by about 32.55%when the channel saturation rate is 20%;(3)Completed the reconstruction and development of the MAC layer protocol based on the OpenWRT platform,tested the frame interaction and scheduling process,and carried out a pilot application in a real electric scenario;Test and pilot results show that this MAC protocol can meet the throughput and basic interaction requirements in electric broadband scenarios.In summary,this thesis analyzed the requirements of electric scenarios and designed an optimized MAC layer protocol,which is verified by simulation and field trial.This protocol provides an effective solution for the broadband business needs of the electric Internet of things.