GE Reason RT430 Technical Manual page 98

GPS Grandmaster Clock
The antenna cable delays GPS signal. In applications in which the ultimate time accuracy is desired, this
delay should be compensated inside the unit.
Typically, the delay introduced by coaxial cables is in the magnitude of 4 ns/m (1.2 ns/ft) of cable length.
The exact delay can be computed by using:
Where C =
and is the cable length in meters.
The table below summarizes some typical delays caused by coaxial cables
98
m/s is the speed of light,
Tabela D.2: Atenuação de cabos de antena.
Cable length
m (50 ft)
m (82 ft)
m (164 ft)
m (246 ft)
m (328 ft)
m (410 ft)
m (492 ft)
is a constant which depends on the cable
Tipical delay
60 ns
100 ns
200 ns
300 ns
400 ns
500 ns
600 ns
RT430-TM-EN-5