Connecting microwave photonic MIMO radar research across fields

Microwave photonic multiple-input multiple-output (MIMO) radar is a rapidly developing technique that could be used to create high-resolution images for applications in drone and autonomous vehicle monitoring, surveillance, security, industrial inspection, and more. The technique combines microwave photonics technology, which can outperform traditional electronic radars in bandwidth, delay, electromagnetic interference, and integration, with MIMO radar to improve resolution, tracking, and efficiency.

However, work on this technique is distributed across the fields of photonics, radar, and signal processing. Pan et al. gathered all the progress related to microwave photonic MIMO radar into one paper, providing a systematic, unified overview of this technique.

“This review transforms fragmented advances into a coherent roadmap, making it a landmark for the entire cross-disciplinary field,” said author Fangzheng Zhang. “It could act as a collaboration bridge, fostering partnerships between photonic chip developers, radar system integrators, and digital signal-processing teams.”

To explain the fundamental principles of microwave photonic MIMO radar, the authors described how this new technique links microwave photonic technology, such as broadband signal generation, frequency conversion, and low-loss fiber transmission, with MIMO radar mechanisms, including waveform orthogonality, virtual array, and digital beamforming. They presented key experiments that demonstrated the effectiveness of microwave photonic MIMO radars in high-resolution target detection and imaging applications, and compared the performance of different system architectures.

“Whether you are a student, researcher, or engineer, this review accelerates your entry and sharpens your research focus in this high-growth area,” Zhang said. It could also serve as a guide for researchers designing microwave photonic MIMO radar prototypes.

For future research related to this technique, the authors identified unresolved challenges, such as real-time processing, as well as future development directions, including improving efficiency, realizing artificial intelligence-assisted processing, reducing system size, and developing stealth-target detection.

Source: “Microwave photonic MIMO radar,” by Shilong Pan, Yuewen Zhou, and Fangzheng Zhang, APL Photonics (2026). The article can be accessed at https://doi.org/10.1063/5.0320725 .