acceleration 
an inertial 
system for 
1 attitude 
ystems, not 
I varieties, 
strapdown 
he internal 
a platform 
coordinate 
>ss is done 
o the body 
on changes 
. Although 
m at hand, 
ms of data 
quirements, 
lerefore be 
s function 
short-term 
Because of 
long-term 
ficient for 
ion and/or 
rors within 
al systems 
ised. which 
We will 
medium 
je 4 using 
r interval 
erefore an 
:tand-alone 
interval 
accuracy, 
cycle slip 
aracterizes 
, assuming 
accuracies 
re three to 
can vary 
; used. In 
se levels if 
y designed 
stems can 
ven in that 
the other 
ar superior 
Thus, for 
, both the 
system are 
accuracies 
It appears 
. the best 
ver a wide 
  
System Accuracy Class (rms) 
  
  
Error in high medium low 
Attitude 
1h 10" - 30" l'-3 1°-- 3° 
1 min 1 2 15-20" 02-073 
1s « A" 1 0°.01 - 0°.03 
50Hz (noise) 0".1 - 0"2 0*1- 0*2 15" - 20" 
Velocity 
1h 0.3 - 0.5 m/s 1 -2 m/s 200 - 300 m/s 
| min 0.01 - 0.02 m/s 0.05 - 0.1 m/s 1-2 m/s 
ls 0.0005 - 0.001 m/s 0.001 - 0.003 m/s 0.002 - 0.005 m/s 
50 Hz (noise) 
0.0002 - 0.0005 m/s 
0.0005 - 0.002 m/s 
0.001 - 0.003 m/s 
  
  
  
  
  
  
  
  
  
  
  
  
  
Position 
lh 0.3 - 0.5 km 1 - 3 km 200 - 300 km 
1 min 0.3 - 0.5 m 0.5-3.0 m 30-50m 
ls 0.01 - 0.02 m 0.03-0.10 m/ 0.3 - 0.5 m 
50 Hz (noise) 0.005 - 0.001 0.001-0.005 m 0.05 - 0.10 m 
Table 4: INS Position, Velocity, and Attitude Accuracies 
Accuracy System Airborne Cost Characteristics 
Required Configuration Sensor (K$=$1000) 
0.05 - 0.1 m High accuracy INS plus All airborne sensors K$250 Suitable for all 
15" :30" DGPS (carrier phase) applications 
0.0002 - 0.0005 m/s 
0.05 - 0.1 m DGPS (carrier phase) Photogrammetric camera K$50 Block adjustment only 
2-5m DGPS (pseudo-range) plus | Pushbroom scanner, CCD K$50 Low data rate. Attitude 
2 10' GPS multi-antenna system frame imagers transfer to imaging 
0.01 - 0.02 m/s sensor is problematic 
(stability) 
2-5m DGPS (pseudo-range) plus Pushbroom scanners, K$100 - 120 | Long-term velocity may 
21 medium accuracy INS CCD frame imagers, some be marginal 
0.0002 - 0.0005 m/s SAR applications 
  
  
  
  
  
  
  
Table 5: 
6. POSSIBLE SENSOR CONFIGURATIONS 
In Table 5, the possible sensor configurations for each 
accuracy range are given and some advantages and drawbacks 
are listed. A cost estimate based on current hardware costs is 
also attached. It does not include interfacing of the sensors 
and dedicated software development which will be necessary 
in most cases. It also does not include aircraft installation 
and certification which usually adds considerably to the 
Possible Sensor Configurations 
costs. Considering, however, that such a system would 
eliminate all need for ground control, except the minimum 
required for calibration, the overall costs are reasonable. 
Table 5 shows that it is possible to develop a 
georeferencing system for airborne remote sensing that 
meets all current accuracy requirements by integrating 
available INS and GPS hardware components. To achieve 
the position accuracy for high precision engineering and 
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