Fig. 1. Autocorrelation function of Barker codes with different code lengths

Fig. 2. Barker code excitation principle

Fig. 3. Principle of 3D matched filter

Fig. 4. Defect distribution of honeycomb specimen

Fig. 5. Analysis of simulation data

Fig. 6. Original data analysis of simulation and experiment

Fig. 7. [in Chinese]

Fig. 7. Results comparison of algorithms with debonding defect as the target

Fig. 8. [in Chinese]

Fig. 8. Results comparison of the algorithms with water accumulation defect as the target

Fig. 9. SNR evaluation criteria

Fig. 10. Reliability evaluation of different algorithms