Abstract | Full Paper | PDF | Printer friendly format

Page 2 of 2
| Previous |



Fuzzy Algorithm for 3d Bathymetry Simulation from Topsar Polarised Data

Results and Discussions
Figure 1 shows the regions of interest that used to simulate the bathymetry information from L-Band with HH polarization. The bathymetry information have extracted from of the 4 sub-images, each sub-image was 512 by 512 pixel. Figure 2 shows the signature of underwater topography. Underwater topography is obvious as a frontal lines parallel the shoreline.


Figure 1. Selected Window Size


Figure 2. Signature of Bathymetry

Figure 3. Shows the current spectra density, which varied along the distance. The current intensities varied along the range direction. The maximum current speed is 1.3 m/s. This is because of the fact that Volterra series expansion considers as linear transform. This result confirms the finding of Maged (1994).


Figure 3. Simulation of current flow from TOPSAR data

Figure 4 shows the 3 D bathymetry simulations over different locations. It is obvious that the coastal water bathymetry along the locations A, B, C, D have a gentle slopes and moving parallel to the shoreline. The bathymetry at location E shows a sharp slope. This could be due to strong current flow from the mouth river of Kuala Terengganu. This study confirms the study of Maged et al., (2002).


Figure 4. 3-D Bathymetry Fuzzy Reconstruction at (a) Locations A , B,C, and D and (b) E

Conclusion
This study has introduced a new approach in 3-D reconstruction of coastal waters bathymetry. The integration between Volterra model and the Fuzzy B-Splines method can provide a 3-D construction for coastal waters bathymetry. This approach can provide characteristics of coastal waters bathymetry. In 3-D reconstruction of coastal bathymetry will be easy to detect the gentle and sharp slope. Utilization of composite TOPSAR L-band polarized data (HH) assists in 3 D bathymetry reconstructions.

References
  • Anile, AM, (1997) Report on the activity of the fuzzy softcomputing group, Technical Report of the Dept. of Mathematics, University of Catania, March 1997, pages 10.
  • Alpers, W., and I., A. Hennings, 1984. theory of the Imaging of Underwater Bottom topography by Real and synthetic Aperture radar. Journal of Geophysical research, Vol.89C, pp10,529-10,546.
  • Inglada J., and R. Garello 1999. Volterra Model for imaging mechanism of ocean surface currents by synthetic aperture radar. In proceedings of IGARSS’99.
  • Hesselmans, G.H, G.J Wensink C.G. V. Koppen, C. Vernemmen and C.V Cauwenberghe , 2000. Bathymetry assessment Demonstration off the Belgian Coast-Babel. The hydropgraphic Journal . No.96. pp.3-8.
  • Maged M, 1994 “ Coastal Water Circulation off Kuala Terengganu, Malaysia”. MSc. Thesis Universiti Pertanian Malaysia.
  • Maged M., H. L. Mohd., and K., Yunus (2002) TOPSAR Model for bathymetry Pattern Detection along coastal waters of Kuala Terengganu, Malaysia. Journal of Physical Sciences. Vol (14)(3), 487-490.
  • Zebker, H. A., 1992. The TOPSAR interferometric radar topographic mapping instrument. IEEE Transactions on Geoscienceand Remote Sensing, vol. 30, pp. 933-940, 1992.

Page 2 of 2
| Previous |