Coordinating waveforms and receivers for stronger MIMO radar signals
Complementary Waveform Coordination for Doppler-Resilient MIMO Radar
Information Theory
Summary
MIMO radar systems send out multiple waveforms to detect objects by measuring reflected signals. The challenge is that certain signal combinations cancel out important details when objects move, causing weaker detection. The authors developed a new way to mathematically coordinate which waveforms are sent and how the receiver listens, reducing these cancellations even when targets move. Their method improves signal clarity over previous approaches and works well with multiple waveforms.
What this means in practice
- •For radar system engineers: Optimize radar waveform schedules and receiver settings for better detection of moving targets with fewer signal distortions.
- •For defense communication specialists: Design Doppler-resilient radar signals that maintain clarity against fast-moving objects in complex environments.
Authors
Maksim Antonik, Wenbing Dang, Ali Pezeshki, Stephen D. Howard, William Moran
Abstract
Complementary waveform libraries yield impulse-like aggregate delay responses at zero Doppler, but pulse-dependent Doppler phases degrade their sidelobe cancellation. This paper develops a linear-algebraic formulation for coordinating a (D)-ary transmission schedule and slow-time receive weights for paraunitary MIMO waveform libraries. Using a modal decomposition of the CPI ambiguity matrix, prescribed-order Doppler-nulling conditions for the (D-1) nonzero modes are expressed as homogeneous linear constraints on the receive weights for a fixed schedule. This representation gives the SNR-optimal fixed-schedule weights by subspace projection and reduces the remaining design to a discrete schedule search. Degrees-of-freedom and modal-growth analyses relate the design to the CPI length, null order, and waveform dimension. Numerical examples compare the resulting designs with established binary constructions and demonstrate Doppler suppression across the full ambiguity matrix of a four-waveform configuration.