Development of Comparison System of Several Atomic Clocks ...
Transcript of Development of Comparison System of Several Atomic Clocks ...
NIM, Changping, Beijing, China, 31 October, 2015
Development of Comparison System of Several
Atomic Clocks for Contribution to TAI and UTC
Asep Hapiddin, A. M Boynawan, Ratnaningsih
Research Center for Metrology-Indonesian Institute of Sciences, Puslit Metrologi-LIPI Komplek PUSPIPTEK Building 420, Setu, Tangerang Selatan, Indonesia 15314
Email: [email protected]
Asia Pacific Workshop on Time and Frequency 2015
Outline
Motivation of work
Comparison System for 2 Atomic Clocks against UTC(KIM)
Result of Reference Time Delay Measurement
Conclusion and Future Plans
Motivation of Work
Atomic Clocks Ensemble and Status in RCM-LIPI
For performance checking purposes, the
operating parameters of all clocks
Using manual procedure once per day
All clocks are in normal condition
Continuously monitored
results
using
Motivation of Work
Atomic Clocks Ensemble and Status in RCM-LIPI
As supernumerary clock, Cs3 and Cs4 have not
contribute to TAI and UTC
Comparison System of Atomic Clocks for
Contribution to TAI and UTC
Reference Time Delay Measurement of Cs3 and Cs4
was initial research Activity Time interval Measurement Methods
Need
1st step
Comparison System for 2 Atomic Clocks against UTC(KIM)
Cs3,
Symmetricom
5071A
Arbitrary
Point
rear panel
Time Interval Counter, SR620
1 pps
1 pps
StopStart
10 MHz,
Ext. Ref
Cs1
Arbitrary
Point
rear panel
Time Interval Counter, SR620
1 pps
1 pps
StopStart
10 MHz,
Ext. Ref
Cs1,
HP5071A
10 MHz
Pulse Distribution
Amplifier
UTC(KIM)
input Cs3,
Symmetricom
5071A
Arbitrary
Point
rear panel
Time Interval Counter, SR620
1 pps
1 pps
StopStart
10 MHz,
Ext. Ref
Cs1
Cs4,
Symmetricom
5071A
Cs3,
Symmetricom
5071A
Time delay measurement of Cs3, UTC(KIM) and Cs4 against arbitrary point (AP).
Comparison Cs3 - AP UTC(KIM) - AP Cs4 - AP
ns
Time Delay 0.774 11458.600 9450.836
1st step: time delay measurement of UTC(KIM), Cs3 and Cs4 against arbitrary point (AP) directly. 1 pps front panel output of Cs3 was decided as arbitrary point
Comparison System for 2 Atomic Clocks against UTC(KIM)
rear panel
Time Interval Counter, SR620
1 pps1 pps
StopStart
10 MHz,
Ext. Ref
Cs1,
HP5071A
10 MHz
Pulse Distribution
Amplifier
UTC(KIM)
input
1 pps
Cs3,
Symmetricom
5071A
Cs4,
Symmetricom
5071A
rear panel
Switch,
Agilent 3499B
Time delay measurement results of Cs3 and Cs4 against UTC(KIM) using switch
The second step was time delay measurement of 1 pps rear panel output of Cs3 and Cs4 against UTC(KIM) using switching by Agilent 3499B.
Comparison Cs3 - UTC(KIM) Cs4 - UTC(KIM)
ns
Time Delay -11471.800 -2022.184
Arbitrary Point
9450.836 ns
11458.600 ns
0.774 ns
Cs3 Cs4 UTC(KIM)
0
2000
4000
6000
8000
10000
12000
Dela
y T
ime (
ns)
1 pps Signal of
Cs3-UTC(KIM) = -11471.800 ns
Cs4-UTC(KIM) = -2022.184 ns
The result of time delay measurement of Cs3 and Cs4
So, the reference time delay of Cs3 and Cs4 can be determined by: 𝒌𝑪𝒔𝟑 = ∆𝒕𝟑 − ∆𝒕𝟏 = 𝟏𝟑. 𝟗𝟕 ns and 𝒌𝑪𝒔𝟒 = ∆𝒕𝟒 − ∆𝒕𝟐 = 𝟏𝟒. 𝟒𝟐 ns
The result of time delay measurement Cs3 and Cs4
Result of the reference time delay measurement of Cs3
Dt1
Cs3 UTC(KIM)
Cs3 UTC(KIM)
= 11457.8 ns
Dt3= 11471.8 ns
Time Delay of Cs3 against
UTC(KIM) without switch
Time Delay of Cs3 against
UTC(KIM) using switch
Reference time
delay of Cs3 =
13.97 ns
Cs4 UTC(KIM)
Cs4 UTC(KIM)
Dt4 = 2022.2 ns
Time Delay of Cs3 against
UTC(KIM) without switch
Time Delay of Cs4 against
UTC(KIM) using switch
Reference time
delay of Cs4 =
14.42 ns
Dt2 = 2022.2 ns
Result of the reference time delay measurement of Cs4
Conclusion and Future Plans
By the manual monitoring of all clocks in the RCM-LIPI time scale system, it
was known if Cs1 as master clock for UTC(KIM) and two other clocks (Cs3 and
Cs4) are running in normal condition.
The initial research activity in developing comparison system of three
commercial Cs atomic clocks in RCM-LIPI has done. Then, the reference time
delay of two clocks (Cs3 and Cs4) as supernumerary clocks of Cs1 was
measured against UTC(KIM).
In the near future, we have planned to develop the automatic monitoring
system of all clocks.
We will improve the comparison system by continuous measurement with
automatic system. Then, we will report the reference time delay of each clock
to BIPM. So, all clocks may contribute to TAI and UTC.
Operating Parameters of Cs1, Cs2 and Cs4 From MJD 57174 - MJD 57234
57180 57200 57220 57240
-2
0
2
4
6
8
10
12
Cs-1
Cs-2
Cs-3
Ion
Pu
mp
(u
A)
MJD
Ion Pumps of Cs1, Cs3 and Cs4 (MJD57174 – MJD57234). Based on data in specification, normal condition is in the range 0-40 uA.
Operating Parameters of Cs1, Cs2 and Cs4 From MJD 57174 - MJD 57234
Oven monitors of Cs1, Cs3 and Cs4 (MJD57174 – MJD57234). Based on data in specification, normal condition is in the range 0-10 V for CBT and -10 to -5 for Osc
57180 57200 57220 57240
-10
-8
-6
-4
-2
0
2
4
6
8
CBT Cs-1
Osc Cs-1
CBT Cs-3
Osc Cs-3
CBT Cs-4
Osc Cs-4
Ov
en
Mo
nit
or
(V)
MJD
Operating Parameters of Cs1, Cs2 and Cs4 From MJD 57174 - MJD 57234
Osc Frequency Control of Cs1, Cs3 and Cs4 (MJD57174 – MJD57234). Based on data in specification, normal condition is in the range -95% to 95%.
57170 57180 57190 57200 57210 57220 57230 57240
-30
-25
-20
-15
-10 Cs-1
Cs-3
Cs-4
Os
c F
req
Co
ntr
ol (%
)
MJD
Operating Parameters of Cs1, Cs2 and Cs4 From MJD 57174 - MJD 57234
C-Field Control Current of Cs1, Cs3 and Cs4 (MJD57174 – MJD57234). Based on data in specification, normal condition is in the range 10.00 mA to 14.05 mA
57180 57200 57220 57240
12.12
12.13
12.14
12.15
12.16
12.17
12.18
12.19
12.20 Cs-1
Cs-3
Cs-4C
-Fie
d C
on
tro
l C
urr
en
t (C
s-1
,3, 4-m
A)
MJD
Operating Parameters of Cs1, Cs2 and Cs4 From MJD 57174 - MJD 57234
RF amplitude of Cs1 (MJD57174 – MJD57234). Based on data in specification, normal condition of RF amplitude A and B are in the range 0 to 100%.
57180 57200 57220 57240
26.0
26.5
27.0
27.5
28.0
28.5
29.0
A(%)
B(%)
RF
-Am
plitu
de (
A,B
,%)
MJD
Operating Parameters of Cs1, Cs2 and Cs4 From MJD 57174 - MJD 57234
Electron multiplier voltage of Cs1, Cs3 and Cs4 (MJD57174 – MJD57234). Based on data in specification, normal condition of electron multiplier voltage is in the range 1000 up to 2553 V
57180 57200 57220 57240
1000
1200
1400
1600
1800
2000 Cs-1
Cs-3
Cs-4E
lec
tro
n M
ult
iplie
r V
olt
ag
e (
Cs
-1,3
,4, V
)
MJD