Abstract: Based on the analysis of the integrated observation geometry, a criterion for navigation satellite optimal selection is presented from the perspective of interferometric SAR(InSAR)height precision requirement. The criterion is established by combining the parameters of the InSAR observation, the global navigation satellite system(GNSS)based relative positioning and the coordinate system conversion. The InSAR height error propagation coefficients are also theoretically derived. The new criterion aims at carrying out optimal navigation satellite selection directly by InSAR height precision. The error contribution of each baseline component to the height error is also embodied under the integrated geometric relationship. Simulation results agree well with the theoretical derivation. Comparisons are also carried out for a variety of scenarios, such as different GNSS, different number of selected satellites, and different InSAR parameter configurations. Compared with the traditional satellite selection criterion based on minimal relative dilution of precision, the new criterion can reflect the practical geometric relationships more precisely, which may lead to a higher precision of InSAR height acquisition under the same observation conditions through satellite selection.

Key words: interferometry, synthetic aperture radar, navigation systems, satellite selection, error propagation, error analysis