Formation of MIMO SAR Mini-Satellites - Performance Prediction.

A coherent formation of $N$ identical SAR satellites is considered in this paper. These sensors transmit at the same time, code, and frequency with no synchronization whichever, but for the timing of the arrivals, creating a Multiple Input Multiple Output (MIMO) configuration. The contemporaneous transmission of N signals is expected to result in a reciprocal interference that leads to an illumination pattern that changes in space and time. In spite of this, the increased number of phase centres (w.r.t. single satellite and SIMO cases) can be used to mitigate the interference and to raise the SNR of the equivalent system. The principles of a recombination algorithm are summarized. In order to evaluate the effectiveness of the MIMO reconstruction and to fully characterize the IRF of a MIMO system from a quantitative point of view, new performance figures of merit are defined.