## 2 Materials
### ENVISAT Data  
In March 2002, ESA launched the ENVISAT mission, a multi-sensor satellite equipped with the C-band ASAR sensor, thus ensuring the continuity of data acquisition with the previous ERS-2 mission (as also shown in Figure 1) [46; 47]. This polar-orbiting satellite measured the atmosphere, ocean, land, and ice until April 2012.  
ASAR was a key instrument, featuring a coherent SAR system with distributed transmitter and receiver elements. ASAR offers five polarization modes, VV, HH, VV/HH, HV/HH, and VH/VV, and the following mutually exclusive acquisition modes:  
1. Global Monitoring (GM): This mode uses ScanSAR to generate low-resolution images (1 km) over a 405 km swath in HH or VV polarization;
2. Wave Mode (WM): This mode measures changes in sea surface backscatter due to ocean waves, generating vignettes of 5 km \(\times\) 5 km size with 100 km along-track spacing in HH or VV polarization;
3. Image Mode (IM): This mode produces high-resolution products (30 m) on one of seven swaths spanning incidence angles from 15 to 45 degrees in HH or VV polarization;
4. Alternating Polarization (AP): This mode generates high-resolution products like in IM but with polarization changing between subapertures within the synthetic aperture. ScanSAR is used without varying the subswath, resulting in two images of the same scene in different polarization combinations (HH/VV or HH/HV or VV/VH) with approximately 30 m resolution;
5. Wide Swath (WS): This mode uses ScanSAR to provide medium-resolution images (150 m) over a 405 km swath in HH or VV polarization, composed of five subswaths transmitted in turn to build up continuous along-track images for each subswath.  
Finally, it should be noted that in Stripmap (IM) mode, ASAR covers up to 100 km with a single swath with a spatial resolution of about 5 m (azimuth) and 20 m (ground range).  
The main operational parameters of the ASAR products, made accessible from ESA archives [48], are summarized in Table 1.  
In our research, we profit from the main outcomes of a previous study [49; 41], describing the most impressive results obtained by applying the DCA methodology to ASAR data related to the coastal area of the northern Adriatic Sea (Northeast Italy), collected on Ascending (track 358) and Descending (track 351) orbits. Unlike [49; 41], in this work, we use one single ENVISAT ASAR data frame acquired on the Ascending orbit. Figure 2 shows the location of the test-site area. Specifically, the red rectangle highlights the swath of the ASAR frame used for the experiments shown in this study.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Parameter** & **Value** & **Unit** \\ \hline Wavelength (Center & 0.05624624 & m \\ Frequency) & & \\ Band type & C & \\ Instrument mass & 832 & kg \\ Platform velocity & 7120 & m/s \\ Pulse Repetition Frequency (PRF) & 1650 to 2100 & Hz \\ Chirp bandwidth & up to 16 & MHz \\ Polarization modes & Single VV, HH, or Dual VV + HH, VV + VH, & \\  & HH + HV & \\ Antenna size & 10 \(\times\) 1.3 & m \\ Incidence Angle range & 15\({}^{-45}\)\({}^{\circ}\) & degree \\ Acquisition modes & GM, WM, IM, AP, WS & \\ \hline \hline \end{tabular}
\end{table}
Table 1: ENVISAT/ASAR parameters.