Quality assessment of coherence between 35-day and tandem modes in ERS-1/2 interferometric studies

Abstract

In this paper, we assess the quality of the coherence component γ derived from both tandem and repeat pass interferometric pairs. We first analyze the behavior of the coherence for various window sizes (number of looks). Results show that coherence is very sensitive to window size. A compromise between window size and resolution have to be found in order to better estimate the coherence. We present the first results of simulations using a simple statistical model for the coherence in order to evaluate the noise. Moreover, we investigate the suitability of 35-day repeat pass for landuse classification. Repeat pass interferometry (35 days) is not appropriate for this application. Nevertheless, a combination of γ derived from tandem pair, and the Δγ obtained from both tandem and repeat pass pairs should give useful information land-use classification.