MIMO OFDM Robust Transceiver Design for Clutter Suppression in ISAC Systems

The multiple-input multiple-output (MIMO)-orthogonal frequency division multiplexing (OFDM) waveform strategy is regarded as an advanced technique for implementing vehicle-to-infrastructure (V2I)-integrated sensing and communications (ISAC) systems. However, studies on communication symbolic randomness and environmental uncertainty, especially clutter information instability, are inadequate in ISAC systems. To fill this gap, we propose a robust MIMO-OFDM transceiver design for clutter suppression with environmental statistical characteristics that take both sensing and communications into account. Thus, we jointly optimize the ergodic achievable rate and the outage-constrained radar minimum signal-to-clutter-plus-noise ratio under the power, transmit beampattern shaping, and receiving filter constraints. To tackle the nonconvex problem, Jensen's inequality and Bernstein-type inequality are introduced to establish convex constraints with closed-form approximations, and then the alternating optimization-based algorithm is presented to iteratively solve subproblems. Finally, the effectiveness and robust anti-clutter capability of the proposed method are simulated numerically.