Calibration to Mitigate Near-Field Antennas Effects for a MIMO Radar Imaging System.

Area of Science:

• Radar Systems Engineering
• Electromagnetics and Signal Processing
• Metrology and Calibration

Background:

• High-resolution imaging systems require precise calibration to mitigate errors.
• Hybrid Multiple-Input Multiple-Output (MIMO) radar offers enhanced imaging capabilities but presents unique calibration challenges.
• Undesired antenna effects can degrade the accuracy of radar imaging systems.

Purpose of the Study:

• To develop and present an effective calibration method for a high-resolution hybrid MIMO turntable radar imaging system.
• To address and correct position shifts caused by unwanted antenna effects.
• To improve the overall accuracy and reliability of the radar imaging process.

Main Methods:

• Utilized a line of small metal spheres as a calibration test pattern.
• Analyzed and modeled unwanted effects in the antenna near-field responses.
• Leveraged the symmetry and differences in the MIMO configuration's responses for mitigation.

Main Results:

• Successfully measured position shifts attributed to antenna effects.
• Developed a model to understand and predict these unwanted effects.
• Significantly mitigated the impact of near-field responses on imaging accuracy.

Conclusions:

• The proposed calibration method effectively corrects position shifts in hybrid MIMO radar systems.
• Modeling and exploiting MIMO configuration properties are key to mitigating antenna effects.
• This approach enhances the precision of high-resolution radar imaging.