  This paper addresses robust waveform design for
multiple-input-multiple-output (MIMO) radar detection. A probabilistic model is
proposed to describe the target uncertainty. Considering that waveform design
based on maximizing the probability of detection is intractable, the relative
entropy between the distributions of the observations under two hypotheses
(viz., the target is present/absent) is employed as the design metric. To
tackle the resulting non-convex optimization problem, an efficient algorithm
based on minorization-maximization (MM) is derived. Numerical results
demonstrate that the waveform synthesized by the proposed algorithm is more
robust to model mismatches.
