Integrated Navigation Based on DME+VOR/INS Under the Integrated Radio Condition

In view of the lack of accuracy of INS/GNSS integrated navigation system under the condition of missing satellite navigation (GNSS) signals in specific environment, this paper proposes a DME+VOR/INS integrated navigation method, which tightly coupled INS information and DME+VOR information. For the problem that DME+VOR positioning accuracy is not high and there is a great deal of uncertainty, DME+VOR navigation information is corrected by high dynamic INS navigation information in advance. In view of the existence of the integrate radio system, the information of DME+VOR is uncertain, such as the update time, the new cycle measurement, and the bad environmental interference. By introducing the Sigmoid confidence function, the confidence degree of the information calculated by DME+VOR is extracted. Finally, through the calculation of INS, DME+VOR and electronic compass, the state equation and measurement equation based on EKF are established. The simulation results show that DME+VOR/INS integrated navigation can significantly improve the navigation accuracy of the system, and to meet the navigation and location requirements of the aircraft in the absence of other auxiliary navigation sources such as GNSS signal.