Abstract
1-Overview
2-Common Address Interference Principle
3-Analysis of Vehicle-Mounted Antenna
4-Evaluation Methods
5-Engineering Application Cases
6-Conclusion
7-Reference
Abstract
In order to verify that multiple vehicle-mounted antennas do not appear electromagnetic interference due to integration on the same railway vehicle,an evaluation method suitable for electromagnetic compatibility of vehicle-mounted antennas is proposed. Based on the analysis of the forming factors of antenna interference and the changes of electromagnetic environment before and after loading,the combination of antennas that may produce electromagnetic interference is chosen.Then,the isolation between selected antennas is measured to supplement the evaluation data.Finally,the electromagnetic compatibility between antennas is evaluated by calculating the energy matching of transceiver antennas.The method has been applied to the development of railway vehicles.
Overview
For the railway vehicle, multiple antennas are arranged on the platform with relatively limited space, which is more likely to cause common address interference between antennas.With the emergence of electromagnetic interference problems, vehicle electromagnetic compatibility(EMC) is highly concerned by operators, signal system suppliers, communication system suppliers and vehicle suppliers and other stakeholders. Evaluation of vehicle electromagnetic compatibility has become an important aspect of the development and application of rail transit vehicles.At present, the conformity of vehicle electromagnetic compatibility is mainly evaluated based on the electromagnetic compatibility test results, and the test is mainly conducted according to EN 50121 “electromagnetic compatibility of rail transit” [4].This standard covers the cable port and chassis port, but does not cover the antenna port. Therefore, the test group designed according to this standard cannot directly evaluate the electromagnetic compatibility between antennas after each wireless device is loaded.