A robust on-board tracking technique for spaceborne radar sounders

In spaceborne radar sounder systems, the constraint on data storage imposes an upper bound to the radar receiving window length. Accordingly, an adaptive tracking procedure capable of shifting the receiving window in time according to the topography and spacecraft orbit variations is needed for maximizing the amount of signal acquired from the subsurface. Moreover, spaceborne sounder systems usually have constraints in terms of number of acquisitions and power consumption. Thus, tracking robustness and simplicity are mandatory requirements. In this paper, we present an adaptive range tracking technique derived from a combination of OCOG (Offset Center Of Gravity) leading edge estimation and a-β filter. It gives significant improvements in the loss of lock detection. The performances of the overall technique are evaluated by different simulations of meaningful application scenarios which confirm its effectiveness.