Application of the group keepers of frequency in the composition of non-query measuring station

One of the areas of modernization of GLONASS is due to the creation of a network of the non-query measuring stations performing trajectory measurements of navigation satellites for the GLONASS ephemeris support. For non-query measuring stations, there are high demands on the stability characteristics of the standards of frequency and time, which form the reference signal for the recep- tion of navigational equipment GNSS. Uncontrolled frequency drift of these standards in a stand-alone operation non-query measur- ing stations violates the terms of timing of the receiving equipment generates a loss of phase measurement cycles and, ultimately, reduce the reliability of the results of trajectory measurements [1]. To overcome these difficulties enables the use of a part of non- query measuring stations is not a single standard of frequency and time, and the group keepers of frequency.