The reference system is the SPAN-CPT with NovAtel OEMV-3 
integrated system. The reference solutions were computed by 
the single point positioning (SPP) solutions with Rauch-Tung- 
Striebel (RTS) smoother. The test systems are the C-MIGITS III 
with NovAtel OEMV-3 integrated system and C-MIGITS III 
with U-blox AEK-4T integrated system. And the test systems 
are implemented by the SPP solutions and the Kalman filters 
with non-holonomic constraints to integrate. 
4.2 Field Scenario 
The field scenario of the land vehicle was conducted in the 
downtown area of Tainan, and the total trajectory distance is 5 
kilometers and the work time is 20 minutes. The trajectory is 
displayed in Google Earth as shown in Figure 7, and Figure 8 
shows the building distribution and scenes beside the roads 
went through in the field scenario. The installed instruments on 
the top of the land vehicle can be shown as Figure 9. 
5 
c 
ld scenario 
  
Figure 9. Installation of the instruments 
4.3 Results 
The testing system is composed of the tactical INS (C-MIGITS 
IIT) with low-cost GPS receiver (U-blox) and a geodetic grade 
dual frequency GPS receiver, respectively. The integration 
algorithms to deal with the data fusion in this study are EKF, 
AKF, EKF with NHC and AKF with NHC. The reference 
system is the SPAN-CPT with geodetic GPS receiver integrated 
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XXXIX-B7, 2012 
XXII ISPRS Congress, 25 August — 01 September 2012, Melbourne, Australia 
    
system and the integrated algorithm is RTS smoother processed 
in post-mission with differential carrier phase measurements. 
For testing system, the GPS solutions are proceed with the SPP 
solutions. The PDOP values and visible satellite numbers of the 
geodetic GPS receiver and the low-cost GPS receiver in the 
field scenario are shown in Figure 10 and Figure 11. 
PZOP/Satellia numbers 
  
salve 
ae * Wo v RAT 
28 | 9 oul SR m 0060000 bio (EEE veu, 
  
  
  
EE : pm: m en T 
TELE Ce Cp wr dis 
Figure 10. PDOP and visible satellites of the geodetic GPS receiver 
PROP Satelite rushes 
  
  
   
   
Figure 11. PDOP and visible satellites of the low-cost GPS receiver 
W4.3.1 Tactical INS & Geodetic GPS receiver 
The first scenario is to demonstrate the results of tactical INS 
and geodetic GPS receiver processed by EKF, EKF with NHC, 
AKF and AKF with NHC, respectively. Figurel2 shows the n- 
frame trajectories of the integration algorithms, and positional 
solutions errors in local level frame (East, North and Up 
directions) are shown in Figures 13 to 15. 
  
Farectary 
  
  
  
E ur REPRE EKF 
fm i: sesssexe EE e NHC 
: y N 7 ' summum À KF 
5 3 AKF+NHC 
7 i — Reference 
| ow" de 
i oa tinm, 
T ea LT 
1 i i i 3 
nes A Net we 
  
Tus pon 
fast 
Figure 12. The trajectories of the first test integrated system 
Positioning Error - E 
o EE x