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Multiple-input, multiple-output (MIMO) radars can estimate radial velocities of moving objects, but not their tangential velocities. In this paper, we propose to exploit multi-bounce scattering in the environment to form an effective multi-“look” synthetic aperture and enable estimation of a moving object's entire velocity vector - both tangential and radial velocities. The proposed approach enables instantaneous velocity vector estimation with a single MIMO radar, without additional sensors or assumptions about the object size. The only requirement of our approach is the existence of at least one resolvable multi-bounce path to the object from a static landmark in the environment. The approach is validated both in theory and simulation.
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This content will become publicly available on July 30, 2026
Single-Frame MIMO Radar Velocity Vector Estimation via Multi-Bounce Scattering
Radars are widely adopted for autonomous navigation and vehicular networking due to their robustness to weather conditions as compared to visible light cameras and lidars. However, radars currently struggle with differentiating static vs tangentially moving objects within a single radar frame since both yield the same Doppler along line-of-sight paths to the radar. Prior solutions deploy multiple radar or visible light camera modules to form a multi-“look” synthetic aperture for estimating the single-frame velocity vectors, to estimate tangential and radial velocity components of moving objects leading to higher system costs. In this paper, we propose to exploit multi-bounce scattering from secondary static objects in the environment, e.g., building pillars, walls, etc., to form an effective multi-“look” synthetic aperture for single-frame velocity vector estimation with a single multiple-input, multiple-output (MIMO) radar, thus reducing the overall system cost and removing the need for multi-module synchronization. We present a comprehensive theoretical and experiment evaluation of our scheme, demonstrating a 4.5× reduction in the error for estimating moving objects’ velocity vectors over comparable single-radar baselines.
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- PAR ID:
- 10632629
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Transactions on Computational Imaging
- Volume:
- 11
- ISSN:
- 2573-0436
- Page Range / eLocation ID:
- 1005 to 1019
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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