IAPRS & SIS, Vol.34, Part 7, “Resource and Environmental Monitoring”, Hyderabad, India, 2002 
ionospheric effects. The time delay was less during early 
morning hours i.e. 0000-0600. The reason for large height error 
compared to positional errors needs to be studied. 
ACKNOWLEDGEMENTS 
Authors express their sincere gratitude to Dr. A.K.S. Gopalan, 
Director, SAC for his initiative and interest in this study. 
REFERENCES 
Abidin, H.Z., Jones, A., Sarah, A. and Anshari, R. 2000. GPS 
ground work: Building cadastral networks. GPS World, 2000, 
te 9(9), pp. 56-62. 
Corbeanu, H., Brikowski, T., Aiken, C. and Enoiu, P.2000.La- 
ndslide monitoring in Romania. GPS World, 2000, 11(3),pp. 
38-42. 
Leick, A., 1990. GPS Satellite Surveying. John Wiley & Sons, 
Inc., pp.01-10. 
nd height 
t (m) 
Min 
7.10 
25.11 
42.12 
22.26 
nd height 
in 
t (m) 
Min 
1.72 
> 52.88 
0.95 
400 hrs 
curacy of 
ncy GPS 
time and 
| the error 
It can be 
at in the 
ion period 
nal due to 
649