Search results
-
V.2(30), 2017
99-112The structure of a complex of locomotive safety devices (CLSD) is analyzed. A comparison of technical characteristics and design features of ground stationary and transport antennas of the receiving equipment of the global satellite radio navigation system (SRNS) is made. On this basis, the importance of using SRNS in the CLSD structure is shown. It has also been shown that the decrease in locomotive positioning errors associated with the need to increase the signal-to-noise ratio at the input of the receiver can be achieved by the use of active phased array antennas (APARs). APAR are able to form narrowly directional patterns with the commutation of their maximum directions in accordance with the coordinates of the constellation's navigation satellites. Features of the formation of narrowly directional patterns and the possibility of controlling them in a linear and flat uniform APAR are considered. It is shown that the use of APAR in the ground-based equipment of the user is associated with the need: a) changing the approach to designing it for specific applications, - a flat surface of the required size should be provided in the design; b) the modernization of the algorithm for receiving and processing SRNS signals, which must take into account the finite switching time of the radiation patterns, the angle of the mask, the number and coordinate distribution of the navigation satellites in the working constellation.