Techniques for allowing a remote or fielded receiver to derive a precise time reference (such as Coordinated Universal Time (UTC)) when the fielded receiver is not able to derive time directly from received GPS signals. One or more fixed DME reference stations are located within range of DME beacon signals from an existing DME beacon station, the DME reference stations also having the capability to receive GPS signals and derive UTC therefrom. Based on the known distance between the DME reference station and the DME beacon station, the DME reference station can determine the time of transmission from the DME beacon station of each DME beacon signal. This time tag information is then provided to the fielded receiver, which is also within range of DME beacon signals from the DME beacon station. With this time tag information, the fielded receiver can correlate that with the received DME beacon signals and derive UTC to within an acceptably small margin.
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