Patent ID: 8392743

Claim:
A master clock generation unit for satellite navigation systems, said master clock generation unit comprising: a first atomic clock signal having a first reference frequency and a second atomic clock signal having a second reference frequency, wherein the first and second reference frequencies are different frequencies; a plurality of frequency inputs for receiving one of the first and second atomic clock signals; a plurality of frequency converters each of which has a converter input connected to one of the frequency inputs and a converter output, wherein a first one of the plurality of frequency converters receives the first atomic clock signal and a second one of the plurality of frequency converters receives the second atomic clock signal, each of the frequency converters is supplied with an offset frequency by one or a number of frequency synthesizers, the offset frequency being selected according to whether the frequency converter of the plurality of frequency converters receives the first or second atomic clock signal so that each of the converter outputs provides the same intermediate frequency; a switching matrix connected to each of the converter outputs for selecting one intermediate frequency as a primary clock provided at a first matrix output and another intermediate frequency as a secondary clock provided at a second matrix output; a frequency generator having a generator input directly connected to the first matrix output and connected to a number of frequency outputs of the master clock generation unit, the frequency generator being adapted for deriving an output reference frequency from the primary clock, and providing the output reference frequency at the number of frequency outputs; and a phase meter having a first meter input directly connected to the first matrix output and a second meter input connected to the second matrix output for determining a phase difference between the primary and the secondary clock for detecting abnormal behavior.