CAJ | 학술논문

为实现矿井机车无人驾驶系统，必须解决机车在矿井巷道轨旁AP之间的切换时延问题。典型的切换过程包括MAC层切换和网络层切换，其中MAC层切换包括扫描、认证和重关联3个阶段，其中扫描阶段占切换时延的90％以上，传统的切换机制采用全扫描方式，时延较高，难以满足实时性应用对切换时延的要求。由于AP位置固定且机车的位置可通过定位算法获取到，因此提出基于位置的无缝切换机制，该机制在非连续多个AP出现故障情况下，根据建立的AP信息链表，都能保证机车在确定的位置选择合适的AP进行MAC层切换，在MAC层切换的同时根据网络路由的需要进行网络层切换过程。通过仿真验证表明该切换机制能够降低切换时延60％以上，实现机车在轨旁AP之间的切换延时满足实时系统对时延的要求，实现无缝切换。
위실현광정궤차무인가사계통，필수해결궤차재광정항도궤방AP지간적절환시연문제。전형적절환과정포괄MAC층절환화망락층절환，기중MAC층절환포괄소묘、인증화중관련3개계단，기중소묘계단점절환시연적90％이상，전통적절환궤제채용전소묘방식，시연교고，난이만족실시성응용대절환시연적요구。유우AP위치고정차궤차적위치가통과정위산법획취도，인차제출기우위치적무봉절환궤제，해궤제재비련속다개AP출현고장정황하，근거건립적AP신식련표，도능보증궤차재학정적위치선택합괄적AP진행MAC층절환，재MAC층절환적동시근거망락로유적수요진행망락층절환과정。통과방진험증표명해절환궤제능구강저절환시연60％이상，실현궤차재궤방AP지간적절환연시만족실시계통대시연적요구，실현무봉절환。
In order to achieve the goal of mine locomotive unmanned system , it is necessary to solve the problem of handoff delay caused by the locomotive in mine laneway move from one access point to another one .A typical handoff process includes the MAC layer handoff and the network layer handoff .And the MAC layer handoff consists of three phases: scan, authentication and re-association.More than 90%of handoff delay is caused by scan phase.The tradi-tional handoff mechanism can cause high handoff delay by using full-scan method which is difficult to meet the re-quirements of the real-time applications.Since the position of the access points is fixed and the position of the loco-motive can be obtained by positioning algorithm, Location Based Seamless Handoff Mechanism is presented to solve the problem.According to the access point information list established by the locomotive , the mechanism can ensure that the locomotive can choose the appropriate access point to make the MAC layer handoff at the specified location in the condition of discontinuous multiple access point’s failure case.According to the network route, the network layer handoff can be made at the same time .The simulation validates that the mechanism reduces at least 60% of the handoff delay.Ultimately the goal is achieved and the requirements of the delay for real-time systems are met.