A Fast Calibration Method for Phased Arrays by Using the Graph Coloring Theory

Area of Science:

• Electrical Engineering
• Radar Systems
• Signal Processing

Background:

• Phased array radars require precise calibration for accurate airplane surveillance and tracking.
• Environmental factors like temperature variations and device aging degrade radar performance.
• Calibrating large-scale phased arrays with thousands of antennas is a time-intensive process.

Purpose of the Study:

• To develop a fast and efficient calibration method for phased array radars.
• To address the challenge of time-consuming calibrations in large-scale systems.
• To maintain high accuracy in airplane surveillance and tracking despite performance degradations.

Main Methods:

• The proposed method utilizes graph coloring theory to optimize the calibration process.
• The calibration problem is transformed into a graph coloring problem, minimizing the number of colors (time slots) used.
• Omnidirectional radiation patterns are leveraged to allow simultaneous calibration of multiple antennas by spatially reusing time slots.

Main Results:

• Simulations demonstrate a significant reduction in total calibration time.
• The method effectively recovers the radiation pattern from amplitude and phase errors and noise.
• The proposed method's calibration time is constant and negligible compared to existing methods.

Conclusions:

• The graph coloring-based approach offers a substantial improvement in phased array radar calibration efficiency.
• This method ensures sustained accuracy for airplane surveillance and tracking systems.
• The technique provides a practical solution for managing the calibration of large-scale phased arrays.