Real-Time Air-to-Ground Data Communication Technology of Aeroengine Health Management System with Adaptive Rate in the Whole Airspace

To overcome the problem of data transmission of the aeroengine health management system, a multilink communication system combining ultrahigh-frequency communication link, 4G cellular mobile communication link, and BeiDou satellite communication link was proposed. This system can realize the functions such as data receiving and sending, data encryption, and resuming transfer from the break point based on multiple links. When the flight altitude is not high, the communication distance is short, so the UHF digital transmission radio communication link is adopted, which is highly efficient and stable. When the communication distance is long, the 4G cellular mobile communication link can ensure both the communication distance and the communication rate. In the area where 4G signal cannot be covered in extreme terrain environment, BeiDou satellite communication link is used for data transmission. Besides, in order to ensure the communication rate of the link, a multilink adaptive switching technology was also developed. The test verified that the system can perform adaptive switching among multiple links, realize air-ground data communication in the whole airspace, and achieve a good communication rate, which has significative value of engineering application.

ELECTROMAGNETIC COMPATIBILITY OF RES ON RAILWAY

This work reviews the main related problems of electromagnetic compatibility (EMC) of the locomotive radio system GSM-R in modern railway transport. The typical internal electromagnetic interference (EMI), caused by the high density of the equipment layout in the rolling stock, and external electromagnetic interference generated by public cellular mobile communication networks and other radio systems are considered. The results of experiments to determine the parameters of public cellular mobile communication networks along the selected railway section show a rather high level of signals that are EMI for GSM-R and affecting on EMC.