DME SYSTEM WITH BROADCASTING FUNCTION

摘要

PROBLEM TO BE SOLVED: To broadcast GPS reinforcing data by superimposing the GPS reinforcing data on distance information by effectively using frequency resources of a DME/TACAN band designated as an aviation band. SOLUTION: A header is added to DGPS reinforcing data to be broadcasted to an onboard system by modulating a transmission pulse level of a conventional ground DME(distance measuring equipment) system. The onboard system generates a threshold value of '1' and '0' by a level detecting device 5, detects a stating point of data by a header detecting means 6, and supplies the reinforcing data to the onboard system. Thus, a data broadcasting function is realized by superimposing GPS reinforcing data on distance information of DME. The DME avoids radio interference with an existing ILS, a VOR, ground-to-air radio communication and a broadcasting station since an L band is used.