Through-Wall Imaging With UWB Radar System - KEMT FEI TUKE

4.4 Measurements of the Practical Scenarios 82
according to the required application. The 2D view is suitable image representation
method for most of the objects. For weakly reflecting objects 1D view, or zoomed
2D or 3D view provide a good solution. 3D view with rotation and zooming option
could provide the best solution when it would be possible to implement it in radar
device with relatively simple controlling.
4.4.3 Imaging of the Object Behind a Concrete Wall
The results from scanning of the metal cabinet behind the 60 cm thick concrete
wall are shown in this section. The relative permittivity of the wall was approx.
εrw = 7.7 and wall conductivity approx. σw = 33.2 mS/m. The metal cabinet
has dimension approx. 60 × 40 × 50 cm. The measurement was provided by the
International Research Centre for Telecommunications and Radar, Delft University
of Technology in the Netherlands with M-sequence UWB radar described in Section
2.1.3. Bistatic radar with horn antennas and clock frequency fc = 4.5GHz was
used. The measurement scenario can be seen in Fig. B.0.1 a). The object behind
the wall was scanned by 4 m horizontal antennas movement.
The SAR imaging with precise TOA estimation described in Section 4.1 was
computed after the all preprocessing steps described in Section 2.4 were undertaken.
The antenna beam was also compensated according to the equation (4.1.16)
during migration. The results from measurements are shown in Appendix B.
2D view of migrated image is shown in Fig. B.0.1 b). Here, the whole measurement
scenario including the front wall and the metal cabinet is figured. In order
to focus on the scanned object the zoom in Z direction from Z = 0.8 m - 4 m is
shown in Fig. B.0.1 c). In this case only the metal cabinet without front wall is
visible.
It can be seen that the metallic objets could be imaged with UWB radar even
behind the 60 cm concrete wall if the appropriate colormap is chosen.
4.4.4 Imaging of the Object Behind a Wooden Door
The results from scanning of the metal cabinet behind the wooden door are shown
in this section. The measurement was provided by the International Research
Centre for Telecommunications and Radar, Delft University of Technology in the
Netherlands with M-sequence UWB radar described in Section 2.1.3. Bistatic
radar with horn antennas and clock frequency fc = 4.5GHz was used. The measurement
scenario can be seen in Fig. C.0.1 a). The object behind the door was
scanned by the 1.5 m vertical antennas movement.
The SAR imaging without the wall compensation was computed after the all
preprocessing steps described in Section 2.4 were undertaken. The antenna beam
was also compensated according to the equation (4.1.16) during migration. The
results from measurements are shown in Appendix C.