Continuous-capture microwave imaging

Area of Science:

• Electromagnetics and Signal Processing
• Microwave Imaging Technology

Background:

• Light-in-flight sensing is a developing area for image reconstruction across various wavelengths.
• Existing methods may require prior scene knowledge or have limitations in speed and resolution.

Purpose of the Study:

• To present a novel microwave imaging system utilizing continuous transmit-receive mode.
• To demonstrate real-time image reconstruction with high spatial resolution and coverage.
• To validate the system's performance through simulations and experimental data.

Main Methods:

• An array of transmitters and a single receiver operating in continuous mode capture signals in microseconds.
• An engineered electromagnetic field mask generates unique random time patterns for each scene point.
• Image reconstruction is achieved via a dot product between a reconstruction matrix and the captured signal, requiring no prior scene information.

Main Results:

• The system achieves images covering tens of square meters with 0.1-meter spatial resolution.
• Simulations and laboratory experiments confirm the system's operational capability.
• Demonstrated through-wall real-time imaging, tracking, and observation of second-order images from specular reflections.

Conclusions:

• The developed microwave imaging system offers a promising, non-prior-dependent approach for real-time scene reconstruction.
• The engineered electromagnetic field mask is key to achieving unique spatial-temporal encoding for accurate imaging.
• The system's capabilities extend to through-wall imaging and object tracking, highlighting its potential applications.