Interoperability Test And Wireless Network Planning Of GSM-R Marshalling Yards

As a standard for railway shunting communication, GSM-R has been widely deployed by European railways. Nowadays in China, the method of railway shunting communication is in transition from analogue mode to GSM-R. In the practical application of GSM-R, it is particularly important to achieve the interoperability in order to ensure the interface compatibility between different vendors. Up to now, the static interoperability test among Huawei, Nortel and Siemens has been accomplished in GSM-R labs of the Ministry of Railways, while the field test of actual railways comes into effect.Marshalling yard is a large transfer station along the track and an important point among railway networks. As an integral part of GSM-R field test, IOT for marshalling yard has its unique nature. Specifically, particular configuration of equipment in the network, terrain conditions of marshalling yard, functional needs and operational requirements, in which are slightly different compared with the general station. What's more, it's necessary to design the wireless network of marshalling yard reasonably owing to its large traffic and the scarcity of GSM-R frequency resources.Firstly, the demand of marshalling yard for wireless networks was researched in this paper; Based on the research, three options for transmitting speech and data simultaneously were put forward, and their advantages and disadvantages were discussed at the same time. Secondly, the focus of marshalling yard during field test were investigated in depth; Then taking north Wuhan marshalling yard for example, two IOT strategies for connecting to the core networks of Wuhan were presented, which include the implementation steps, long-distance link budget, network infrastructure, new test cases for transmitting data and speech simultaneously, etc.; Subsequently, the two IOT strategies were analyzed at length from feasibility, complexity, impact on the present network. Thirdly, based on the common voice model for GSM-R and combined with the relevant data, the traffic and the business of north Wuhan marshalling yard was predicted; Then the coverage range of every BTS was deduced by using two-ray model for micro-cellular together with the circumstances and link parameters of marshalling yard; Eventually two wireless network planning schemes were proposed and the optimum one was chosen between them considering the following factors: interferences, complexity, construction period, and convergence to the adjacent lines.