1 PPS
UTC(k)
Time Interval Counter
GNSS antenna
FREQ(k)
10 MHz
1 PPS
Output
GNSS receiver
Observations
Navigation Data
RX Time Solution
EGNOS Messages
AGC Information
RX clock error
Jammer
Optional
Free-running
local oscillator
10 MHz
Local Oscillator
Frequency Error
Frequency Counter
Splitter/
Combiner
GNSS antennaVariable Gain
GNSS Repeater
Time Interval Counter
FREQ(k)
10 MHz
1 PPS
GNSS receiver
RX clock error
Free-running
local oscillator
10 MHz
Local Oscillator
Frequency Error
Frequency Counter
1 PPS
UTC(k)
Long
cable
Observations
Navigation Data
RX Time Solution
EGNOS Messages
AGC Information
100 101 102 103 104
averaging time (s)
10-9
10-8
10-7
M
TI
E
(s
)
ITU mask
SF GPS
DF GPS
SF Galileo
DF Galileo
SF GPS EGNOS
100 101 102 103 104
averaging time (s)
10-12
10-11
10-10
10-9
10-8
10-7
10-6
TD
EV
(s
)
LO without GNSS
ITU mask
SF GPS
DF GPS
SF Galileo
DF Galileo
SF GPS EGNOS
100 101 102 103 104 105
averaging time (s)
10-9
10-8
M
TI
E
(s
)
SF Galileo
SF GPS
100 101 102 103 104
averaging time (s)
10-11
10-10
TD
E
V
(s
) SF Galileo
SF GPS
0 1 2 3 4 5 6 7 8 9
time (s) 104
-100
-80
-60
-40
-20
0
20
tim
e
of
fs
et
(µ
s)
Based on GPS + EGNOS
Based on GPS-only

0 1 2 3 4 5 6 7 8 9
Time (s) 104
-200
-100
0
100
200
Ti
m
e
O
ffs
et
(n
s)
GNSS with KF - nominal values
GNSS with KF - stronger smoothing
GNSS with KF - increased GNSS weight
ITU time offset mask
0 1 2 3 4 5 6 7 8 9
Time (s) 104
-10
-5
0
5
Ti
m
e
O
ffs
et
(n
s)
100 101 102 103 104 105
averaging time (s)
10-9
10-8
10-7
10-6
M
TI
E
(s
)
Galileo DF - Nominal case
Galileo DF with SF fall-back
ITU mask
100 101 102 103 104
averaging time (s)
10-10
10-8
TD
E
V
(s
)
Galileo DF - Nominal case
Galileo DF with SF fall-back
ITU mask
0 500 1000 1500 2000 2500
time (s)
-50
0
50
100
tim
e
of
fs
et
(n
s)
SF GPS
SF GPS + EGNOS
DF GPS
SF Galileo
DF Galileo