92 
- An extensive set of corner reflections (e.g. Figure 1) was 
deployed on two test sites, which were overflown many times 
during the whole campaign. These test sites were overflown at 
different directions and at different heights, with the radar 
operating in all frequencies and polarizations. 
   
APPROXIMATE DIRECTION 
OF FLIGHT RESERVOIR 
  
L nk e ES m asa 
a 0.8 Km 
Figure 1: Bedford Calibration Site 
- Auxiliary data was recorded on-board on a stripchart; other 
parameters were reported on log sheets. (The inadequency and 
inaccuracy of the auxiliary data logging and recording 
organisation proved to be one of the major drawbacks of the 
system.) 
À small project was run in parallel to the data processing 
activities in order to assess the achievable extent of 
calibration, and perform calibration of a restricted data set; 
the main results were: 
- Reconstruction of the antenna pattern from CALSIG data and 
corner reflector data. 
- Definition of a procedure to calibrate a scene in terms of 
Jo (assuming the CALSIG from that scene is available and using 
the derived antenna pattern). 
Figure 2 give examples of the derived antenna pattern. The 
main result of this activity was the acknowledgement of the 
problems related to calibration in a practical case, of the 
methodology to be followed for data collection, and the 
importance of accurate and reliable auxiliary data.