Abstract:
Positioning, navigation and timing (PNT) system is an essential infrastructure for the normal operation of modern society. The achievements made in military, economic and other fields of national economy and people's livelihood in recent years are obvious to all.However, with the increasingly complex highfrequency electromagnetic environment, in order to improve the reliability of PNT system, it is necessary to develop land-based radio navigation system that does not rely on satellite navigation. Land-based radio navigation system has the characteristics of low working frequency and large transmitting power, so it has high reliability and is not easy to be interfered with, and can be used as a backup of satellite navigation system.The development and construction of landbased radio navigation system is of great significance to the establishment of a robust and reliable national positioning, navigation and timing (PNT) system and the guarantee of national security and the development of national economy. This paper analyzes and introduces the development status and trend of landbased radio navigation system at home and abroad.