Incidence angle dependence of PALSAR Repeat Pass Interferometry

Inhalt:
In this paper, we discuss the incidence angle dependence of the PALSAR repeat pass interferometry for coherence and the phase difference. Analyzing the PALSAR data observed for the Hawaii big island in five off-nadir angles (e.g., 9.9, 21.5, 34.3, 41.5, and 50.8), we depicted the incidence angle dependence of the coherence and the phase difference, and also discuss the adequate range of the off-nadir angles for detection of the changes. It shows that the coherence becomes higher for the off-nadir angle ranging from 30 to 50.8 degrees. The reasons were considered by using the signal penetration analysis using the Π-SAR polarimetry over the forest region. It shows that the double bounce is maximized for the incidence angel of 30~50 degrees. This higher contamination of the double bounces in the received signal may contribute to the interferometric processes.