The disclosure relates to the field of time synchronization between {HEAD ~ two geographically separated clocks}, such as {TAIL ~ the stationary clocks} of the phasor measurement units of a wide area monitoring system for a power transmission network 
such as
The disclosure relates to the field of time synchronization between { HEAD ~ two geographically separated clocks } , such as { TAIL ~ the stationary clocks } of the phasor measurement units of a wide area monitoring system for a power transmission network
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH