Institut für Erdmessung
Can Receiver Clock Modeling Influence
Carrier Phase Residuals from Precise
Point Position Solutions?
Le Ren & Steffen Schön
Institut für Erdmessung
Leibniz Universität Hannover
0. Structure





1. Motivation
2. Concept of receiver clock modeling
3. Experiment up
4. Impact on static and kinematic PPP-Solution
5. Conclusion
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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1. Motivation
Troposphere T
1:-3
1:-2
SIGNAL
Station
Height
1:1 - 3:2 Receiver
clock δt
Station height h
•
Can receiver clock modeling influence
carrier phase residuals?
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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2. Concept of receiver clock modeling
Allan deviation
TOXO
„The Allan deviation of the oscillator´s
random frequency errors should be
below the GPS observation noise
projected onto the receiver clock
estimates“
Phase clock
modeling feasible
Schön (2013), Presentation
1 hour
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
1 day
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2. Concept of receiver clock modeling by two states
DGL
 t   f   wt 
      w 
 f  0  f 
Discrete
 tk  1 t   tk 1   wk 1,t 

 f   0 1   f    w
  k 1   k 1, f 
 k 
h0
2 2
2 2
 h0

2
3





t
2
h

t

h

t
?
h

t
 h2 t 2 
1
2
1
2
3
2
3
Qw  

h0
8 2
 h0  2h t  2  2 h t 2
 4h1   h2 t 
1
2
 2

3
2t
3
Noise type
Abbreviation
α
White noise phase modulation
White noise frequency modulation
WPM
WFM
2
0
Flicker noise frequency modulation
FFM
–1
Random walk frequency modulation
RFM
–2
4 2 2
h2     
, h0   y2    2 ,
3 fh
2
y
h1 
 y2  
2
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
, h2   y2   
5
3
 2
3. Experiment set-up
 Antenna: Leica AR25.R4 LEIT
 Receiver: 4 Javad Delta TRE_G3T
 Clock: Active H-maser for Javad 1&2; Rbd for Javad 3&4
Rb
H-maser
Leute (2014) PTB
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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4. Static solution Day 070 Javad 1
Model: static
Clock: H-maser
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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Phase residuals PRN 1 Javad 1
v    T  Tro  B
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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Static solution Day 070 Javad 3
Model: static
Clock: Rubidium
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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Phase residuals PRN 1 Javad 3
Rb clock not suitable for receiver clock modelling in PPP => no impact
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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4. Kinematic Solution Day 070 Javad 1
Model: kinematic
Clock: H-maser
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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Phase residuals PRN 1 Javad 1
v    T  Tro  B
  E  cos El  sin Az  N  cos El  cos Az  U  sin El
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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Kinematic Solution Day 070 Javad 3
Model: kinematic
Clock: Rubidium
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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Phase residuals PRN 1 Javad 3
Rb clock not suitable for receiver clock modelling in PPP => no impact
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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5. Conclusion
 For static model
• no influence on position solution
• ±2 mm on Phase residuals, elevation-independent
 For kinematic model
• no influence on horizontal direction
• smoothed height coordinates
• 5-10 mm on Phase residuals at low elevation
• 2 mm on Phase residuals at high elevation
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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Institut für Erdmessung
Le Ren & Steffen Schön
Institut für Erdmessung
Schneiderberg 50
D-30167 Hannover, Germany
E-Mail: [email protected]
Tel: +49 (511) 762 3892
Fax: +49 (511) 762 4006
URL: http://www.ife.uni-hannover.de/
Leibniz Universität Hannover
Institut für Erdmessung
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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3. Software Set-up
 Extended Kalman filter fwd/bwd
Parameter Type
Static coordinates
Kinematic coordinates
Receiver clock time offset
Receiver clock frequency offset
Tropospheric zwd
Carrier phase ambiguities
Oscillator type
Active H-maser
Rb
TCXO(low quality)
System
Random
Random
Random
Random
Random
Random
model
constant
walk
ramp
walk
walk
constant
-
Correction Set-up: Ionosphere-free LC, tropospheric delay, CODE-Products, DCB,
satellite and receiver antenna PCO and PCV, phase wind-up, relativistic effect,
solid earth tides, ocean loading, pole tides, subdaily pole movement.
Ambiguity: float solution
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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Phase residuals PRN 28 Javad 1
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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Phase residuals PRN 28 Javad 3
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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Phase residuals PRN 28 Javad 1
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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Phase residuals PRN 28 Javad 3
L. Ren & S. Schön – Geodetic Week 2015 – 16.09.2015 Stuttgart
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