## 3 Data Processing of PS-InSAR
Looking at the reflectivity map taken from CSK (X-band) as a sample, the railway, which is a linear-shaped and high-reflective target, is clearly visible in Figure 9.  
Figure 10: PSC maps and scatter plots: (**a**) CSK; (**b**) S1–B/T65; (**c**) S1–B/T160. PSC maps (red line means the railway) and mean velocity maps for CSK and S-1 analyses in LOS direction (dark blue line represents the 30 km-long railway). To compensate for the effect of different incidence angles, the LOS mean deformation velocity was obtained and converted to the vertical direction using Equation (2). Based on train measurements, and previous studies [27; 29; 30; 34; 60; 61] mentioned in Section 1, only the component of displacement should be evaluated as vertical displacement, ignoring horizontal displacement and any potential errors. In addition, LOS deformation is assumed to be purely vertical since the Konya Basin is quite flat and the ascending and descending Sentinel LOS velocities are almost identical, as shown on the right part of Figure 10. In another study conducted in the same region, the following statement is made for vertical transformation. If the deformation is unidirectional, LOS directional deformations that are generated as output may be simply transformed into actual deformation values [34]. \[Vertical\ value=\frac{LOS\ value}{cos(\theta)}, \tag{2}\]  
where \(\theta\) denotes the local incidence angle. In the same whole study area, almost 74,000 and 99,000 PS points (PSs) could be properly estimated from the S1-B/T160 and also S1-B/T65 radar satellites, respectively, while almost 316,000 PSs were from the CSK dataset (Figure 10). The InSAR results obtained from the different datasets were compared to assess their internal consistency, and all results were checked and found to be in good agreement, as seen in the scatter plots in each right part of Figure 10a-c. The difference between the numbers of PSs taken from the different datasets is mainly caused by the higher spatial resolution of the CSK X-band data. Looking at the PSC density maps on the left of Figure 10a-c, it can be seen that the CSK dataset produces more PSs, but there are also many unstable PSs in agricultural and mountainous areas in the region, mainly due to the X-band characteristics. In this analysis, only the PSs on the railway in the study regions were used, and since the temporal coherence of the railway is always stable due to its permanent metallic reflective structure, unstable PSs in areas other than the railway were ignored. Based on the measured amplitude, PSCs are chosen at the start of the processing. After that, their displacement is calculated together with the effects of noise, atmospheric contribution and height correction. PSCs are usually chosen from the candidate pool according to their degree of noise and coherence [40; 48]. APS estimation plays a crucial role in PS-InSAR applications by facilitating the calculation of linear deformation velocities and compensating for topographic height effects [62]. For accurate APS estimation, it is advisable to use an appropriate threshold, typically ASI > 0.75, when selecting initial PSs [63]. Based on this information and for creating a network of PSCs, an ASI threshold value > 0.75 was used and applied to estimate preliminary parameters and APS. A larger set of points, based on the reflectivity map and spatial coherence, was used during the compensation of APS. After APS removal, the final estimates of height and velocity were computed. At the step of visualizing the final results, a threshold ASI index > 0.60 on temporal coherence was used to include more PSs [64] (Figure 10). As a check stage, the reliability of the deformation estimations can be determined utilizing many independent satellite tracks that observe the same deformation signal, which is apparent at each right part of Figure 10[65]. The first research location is a rural region, which results in decreased coherence with the X-band.