| a 
T fh CP 
X 
A L 
EN 
80 #1 ES - ine 
= s 
# MS KK 
+ E e A 
v Bh, 
j e f 
-100 2 Eon ed 
AF TUN 
# 7 
-110 at + 
T W 
A 
n x # 
za NS. x 
RS L^ 
e. 
130 DA a 7 
Ss é 
RN # 
ee ke 
-140 Gnu 
PA 
-150 
SG o o —— OX m o— n —— O0 AO c0 — 0m o8 — cmn 
Figure 9. The trajectory of the car: the symbol + are the post 
processed positions measured by the geodetic 
receiver; the symbols A are the post processed 
positions measured by the low cost receiver. The 
units are meters from the reference station. 
  
-60 
  
  
  
  
  
  
  
  
    
  
  
  
  
  
  
  
  
  
  
  
  
  
-70 S 
= 
E ESS Pres 
e ig 
: CA. TAL AR 
m EN 
-90 we] S * 
Bw b. 
p d a ~. 
-100 VERS Ria [A 
ü , Pes 
41 3^7 
M 
A : 
x 
-120 7 
J 
<A 
B 
-130 7 
à +. Pa 
|. e "n 
-140 vel Cae A f 
- mp 0 
Ye 
ee 
-150 
-360 -350 -340 -330 -320 -310 -300 -290 -280 -270 -260 
Figure 10. The trajectory of the car: the symbol + are the post 
processed positions measured by the geodetic 
receiver; the symbols A are the RTDGPS positions 
measured by the low cost receiver. The units are 
meters from the reference station. Not that the 
RTDGPS solution is 2 seconds rate, due to the 
Garmin NMEA output. 
S. CONCLUSIONS 
We have examined some results in kinematic positioning (PPK, 
RTK and RTDGPS) obtained using geodetic and low cost 
receivers. 
The correct modelling of the biases is fundamental in trajectory 
tracking mainly over long baselines, using a real time 
processing software, as ALARIS. 
With geodetic receivers is possible to obtain results with the 
precision generally required by GIS applications, using 
permanent reference stations. 
With low cost receivers the best results are obtained in PPK, 
while in real time DGPS they are not satisfactory. The work is 
82 
in progress about the real time processing of single frequency 
data, simulating the RTK mode with the software ALARIS. 
REFERENCES 
Gang Lu, 1991. Quality control for differential kinematic GPS 
positioning, Calgary, Alberta. 
Schwarz, K. P., Cannon, M. E,, Wong, R. V. C,, 1989. A 
comparison of GPS kinematic models for the determination of 
position and velocity along a trajectory. Manuscripta 
Geodaetica, 14, pp. 345-353. 
Tabernero Galan, A., 2000. Obtaining raw data from some 
Garmin units, 
http://artico.Ima.fi.upm.es/numerico/miembros/antonio/async/ . 
Teunissen, P. J. G., 1998. Quality control and GPS, Chapter 7 
in GPS for geodesy, Eds. P. J. G. Teunissen and A. Kleusberg., 
Springer Verlag 2™ Edition, 1998. 
Tiberius, C. C. J. M., 1998. Recursive data processing for 
kinematic GPS surveying, Publications on Geodesy 45, Delft, 
Netherlands. 
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