The Research On Satety Transmission Of RBC Message In CTCS-3 Level

In CTCS-3 level train control system, the safety wireless transmission of train-wayside messages plays a vital role. In thesis, EuroRadio protocol was used as the original version, and the RBC and train-wayside wireless messages safety transmission process in CTCS-3 was designed according to EN50159-2 standard. Based on the EuroRadio protocol, AES algorithm was used to calculate MAC yards, besides, dual serial number mechanism was applied, which makes the information more securely and the transportation more efficiently.Firstly, The thesis stated the significance of the safety wireless transmission between RBC and on-board equipment in CTCS-3. Also it introduced the standards and protocols of safety wireless transmission, the principle and the process of safety authentication mechanism in detail.Secondly, according to the overall technical scheme of CTCS-3 level train control system and the application of message wireless transmission in CTCS-3 level train control system, the paper analysed the basic format of main operation scene's messages and news, including the composition of each packet, and packets and fields length in each sending news, etcIn this thesis, AES algorithm, which has higher safety coefficient, was used to improve the algorithm of calculating the MAC, and the principle of this algorithm was introduced. What's more, dual serial number mechanism was adopted to prevent delay and disorderly sequence errors in message transmission. Compared with the timestamp, the author also described the advantages and principles of the dual serial number mechanism.At last, the thesis focused on the detailed process, system composition and interface of message safety wireless transmission between train and RBC. And MAC generative process were described in detail, besides, the RBC center database was designed, in which each data was used to calculate and produce MA and commands for train control. So how to design the database in a reasonable way has a significant influence on the security of wireless packet transmission.