Airborne interferometric SAR: terrain induced phase errors

Motion compensation is critical to successful topographic mapping, with airborne interferometric SAR (InSAR). The pixel dependent phase correction required depends upon the elevation of each scene patch, which is initially unknown, requiring a flat Earth assumption. This leads to terrain induced phase errors in the compressed data, but accurate elevation estimates can still be obtained by interpreting the differential phase of the interferogram appropriately. The single reference track approach to motion compensation inherently compensates for this, while in the double reference track case a phase correction factor must be used