<4D6963726F736F667420576F7264202D2039374F323230315FA668B0D1A6D2AFB8475053B0CABA41A977A6ECBA74BAE2AA6BA4A7ACE3A8735FB2C433BD675F>
183-194 979 183 Journal of Photogrammetry and Remote Sensing Volume
13, No.3, Sepetmber 2008, pp. 183-194
GPS
(1) RTZD RTZD(2)
(3)
1.
(Peal-Time Kinematic, RTK)
184 97 9
2.
2.1
(Double difference)
( ) gh ij
gh g g h h gh gh gh gh ij i j i j ij ij ij ijR T I N vλ λ
Φ Φ = − − + = + − − +
gh ij
gh g g h h gh gh gh ij i j i j ij ij ijR T I v
ρ ρ ρ ρ ρ ρ= − − + = + + +
ij
gh λ
gh ijN gh
ijΦ
GPS
ij m n
gh gh gh gh gh gh ij m n m n ij m n ij m n ij m n ij m n ijR N I T
vλ λ
Φ Φ = = + + + +
+ (4)
, 1 2 gh gh gh ij m n ij ijN mN nN= + ,
gh ij m nI
(m)
+ =
+
(1)(2)(3)
gh wijN L1
1 gh ijN
m (m) 0
2 2 2 /1( )(1 e ) 2
d D mσ σ −
wijN
L1
1, 2, 2 1/ /I I f f =
GPS L1, L2 1 2/ 77 / 60f f = −
77m = ,
60n = − (3)
77, 60 1 77, 60
(77 60 )
gh gh gh ij ij ij
gh gh gh gh ij ij wij ijR N N T
λ
λ λ ε −
gh ijT (2001)
1 1 1 1 1[( ) ( )] 2 cos cos cos cosh g h g
j j i i
= − + − (8)
(8)(7) gh ijT
gh ijT MF z= × (9)
(9)z
'z 0 (m)
l
m
2 iσ
(Accompanying) n × n Ci (n
)
2
1
m
2 iσ Ci
Q
2 1, {1,..., }i i mσ ≅ ∈
Yeh, 2005)
BC B Q (12)
(m=4)
/ ( , , / 2) ( , ,1 / 2)
χ α α
1 2d d
1
RTZD
1
1 1
EΔ , NΔ TWD97(Taiwan
Datum 97, 1997 )
RTZD
1 1 1u u uz a E b N c= Δ + Δ + (15)
1uz RTZD 1uEΔ
iuNΔ 1uNΔ
“Simplified formulae for the BIQUE estimation
of variance components in disjunctive
observation groups.” Journal of Geodesy, Vol. 74,
No. 6, pp. 447-457.
Dai, L., Han, S., Wang, J., and Rizos, C. (2003),
“Comparison of interpolation algorithms in
network-based GPS techniques.” Navigation, Vol.
50, No. 4, pp. 277-293.
Goad, C. C. and Yang, M. (1997), “A new approach
to precision airborne GPS positioning for
photogrammetry.” Photogrammetric Engineering
1067-1077.
Hu, G. R., Khoo, H. S., Goh, P. C., and Law, C. L.
(2003), “Development and assessment of GPS
virtual reference stations for RTK positioning.”
Journal of Geodesy, Vol. 77, No. 5-6, pp.
292-302.
John Wiley & Sons, Inc., Hoboken.
Wu, J. and Yeh, T. F. (2005), “Single-epoch
weighting adjustment of GPS phase observables.”
Navigation, Vol. 52, No. 1, pp. 39-47.
194 Journal of Photogrammetry and Remote Sensing Volume 13, No. 3,
Sepetmber 2008
Research on GPS Kinematic Positioning with Multiple
Reference Stations
ABSTRACT The distance-dependent GPS errors, notably atmospheric
refraction, reduce the success rate of
epoch-by-epoch ambiguity resolution, and limit the GPS positioning
accuracy, especially for medium- to long-range baselines. Using
multiple reference stations to model (or interpolate) the
distance-dependent biases between the reference station and a rover
can extend the distance or improve the positioning accuracy. The
objective of this research is to find out the relative tropospheric
zenith delays (RTZD) between different reference stations by using
known coordinates and to provide rovers with interpolated
corrections for more precise positioning. The project consists of
three major steps: (1) finding out the RTZDs between reference
stations, (2) modeling the RTZDs; (3) kinematic positioning. In the
first step, a pseudo observation equation of RTZD is added in order
to reduce the impact of RTZD on ambiguity resolution. In the second
step, different model is used according to the numbers of reference
stations. These two steps are the emphases of this investigation.
The proposed method needs only one to three epochs to resolve
ambiguities, so the effects of cycle slip or data gap are not very
serious. A multiple reference stations network located in north
Taiwan is used in this research. There are six permanent GPS
stations in this network. Test result indicates that if the RTZDs
between different reference stations can be resolved successfully,
and a proper interpolation model is used, it is possible to improve
the positioning accuracy.
Keywords: Multiple reference stations, GPS kinematic positioning,
Tropospheric zenith delay
1 Graduate Student, Department of Civil Engeneering, National
Central University 2 Professor, Centor for Space and Remote Sensing
Research, National Central
University 3 Ph. D. Candidate, Department of Civil Engeneering,
National Central University
