Mesh Network for Railways

The possibilities provided by the mesh telecommunication network on the railways are examined in the article. Mobile terminal radio stations located on trains are considered as repeaters and moving base radio stations for trains outside the coverage area of base stations of the network. Such a mesh network is represented both as the main communication network on railway lines equipped with an insufficient number of radio base stations and as a backup option in the event of a base station failure on one hand or a decrease in the signaltonoise ratio at the terminal station due to a breakdown on the train on the other hand. The results of a theoretical mathematical calculation of the increase in the effective coverage area of a radio network gained from the use of mesh technology are presented. The results of modeling of the mesh network on the railroad are also presented together with the dependencies of the probability of communication from such factors as: the number of trains on the railway line, the number and range of the base stations, the range of terminal stations, the capacity of the network and the limitation on the number of retransmissions. For the case of using a mesh network as a backup option when a railway line is fully covered with base stations, the results of simulating the time of establishing a connection via a retransmission in the area of a base station failure are presented. Comparison of the possibilities provided by firstorder mesh networks (with one repeater between the terminal and base stations) and more capacious (second and higher orders by the number of allowable repeaters) is presented. As a radio communication standard for mesh network modeling, the application of DMR (Digital Mobile Radio) is considered as a promising one for railway communications, requiring a small number of base stations.