Automated DC offset calibration strategy for structural health monitoring based on portable CW radar sensor

This paper introduces a strategy for automatically selecting dc offset calibration methods on a 2.4-GHz continuous wave (CW) radar sensor, which measures displacement for the purpose of structural health monitoring. Obtaining accurate displacement measurements using CW radar requires the successful application of dc offset calibration. This article compares four commonly applied dc offset calibration methods with a focus on each of the methods' accuracy and efficiency for different measurement signal characteristics. Simulation results are presented to evaluate the accuracy of each method. An advanced systematic strategy for selecting the most appropriate method based on signal characteristics is developed. The automated selection strategy is implemented in software and validated on experimental data.