The Key Technologies And Application Of Mine Wireless Mesh Network

Emerging wireless mesh network has the characteristics of large capacity, high speed, wide coverage, mobility and self-organization. Many problems which can't be solved by the existing mine communication systems will be solved with the application of WMN in coal mine. Designing the structure and the relevant protocols of mine wireless mesh network in order to meet the demand for broadband services are contents of this article. Around the research, this paper made the following aspects of the research.1. Studied and summarized the mine wireless mesh network topology and characteristics, and designed a 3-radio multi-channel network structure by using multi-radio multi-channel technology for the multi-hop long chain backbone network. 3-radio structure allows nodes to concurrently process the local data accessing, data ingressing and data egressing ; Multi-channel distribution allows the chain backbone link to work in K orthogonal channeles in a continuous K hops with no interference to transfer data concurrently. Simulation and actual underground testing (chapter V) show that the 3-radio multi-channel wireless mesh backbone network still maintain high throughput after mulit-hop and can support broadband video transmission.2. Analyzed the backbone link capacity of mine wireless mesh network in theory. Link capacity is the basis of the throughput of multi-hop chain network, depends on the transmission rate of the channel link used. In a certain channel bandwidth conditions, it is related to the value of SINR. The physical model of SINR in underground mine wireless mesh network is derived in this paper and is compared to which on ground. The conclusions is useful for the designing and planning of mine wireless mesh network.3. Proposed a routing metric for mine wireless mesh ring network. In the ring topology of mine wireless mesh network, throughput of path selected to reach wired gateway depends on the path bottleneck link throughput. Based on the routing metric WCETT which proposed by Microsoft, a routing metric of ICETT is proposed in this paper. Compared with the WCETT routing metric, ICETT can more accurately determine bottleneck link of path, so it can select a higher throughput path.4. Designed a mine wireless mesh network routing protocol MIMC-AODV , which is combined with channel assignmeng. During the period of route finding, a strategy same as AODV which is an on-demand routing protocol of Ad Hoc networks is used to find the shortest path. During the period of route replying, interfaces of nodes in found path will be assigned with appropriate channels one by one while these nodes receiving Route Reply in turn. So the channel resources are full used as much as possible to avoid link interferencen. In some special occasions, such as mine rescue after the accident, path with better performance can be select with the using of MIMC-AODV.5. Combined with specific project of "monitoring system of mine endless rope winch transport " , the application of mine wireless mesh network is studied. The program and designing of the system is detailed in this paper. Testing in coal mine show that the system in the mine roadway environment can support video signals transmitting with multiple hops, so a practical problem in coal mine production safety is solved.