1. Marquez, F. P. G., J. M. P. Perez, A. P. Marugan, and M. Papaelias, "Identification of critical components of wind turbines using FTA over the time," Renewable Energy, Vol. 87, 869-883, March 2016.
doi:10.1016/j.renene.2015.09.038        Google Scholar

2. Yang, R., Y. He, and H. Zhang, "Progress and trends in nondestructive testing and evaluation for wind turbine composite blade," Renewable and Sustainable Energy Reviews, Vol. 60, 1225-1250, July 2016.
doi:10.1016/j.rser.2016.02.026        Google Scholar

3. Ciang, C. C., J.-R. Lee, and H.-J. Bang, "Structural health monitoring for a wind turbine system: A review of damage detection methods," Measurement Science and Technology, Vol. 19, No. 12, 122001, December 2008.
doi:10.1088/0957-0233/19/12/122001        Google Scholar

4. Adams, D., J. White, M. Rumsey, and C. Farrar, "Structural health monitoring of wind turbines: Method and application to a HAWT," Wind Energy, Vol. 14, No. 4, 603-623, May 2011.
doi:10.1002/we.437        Google Scholar

5. Lu, B., Y. Li, X. Wu, and Z. Yang, "A review of recent advances in wind turbine condition monitoring and fault diagnosis," Power Electronics & Machines in Wind Applications, PEMWA, 1-7, 2009.        Google Scholar

6. Qiao, W. and D. Lu, "A survey on wind turbine condition monitoring and fault diagnosis — Part I: Components and subsystems," IEEE Transactions on Industrial Electronics, Vol. 62, No. 10, 6536-6545, October 2015.
doi:10.1109/TIE.2015.2422112        Google Scholar

7. Zhou, H. F., H. Y. Dou, L. Z. Qin, Y. Chen, Y. Q. Ni, and J. M. Ko, "A review of full-scale structural testing of wind turbine blades," Renewable and Sustainable Energy Reviews, Vol. 33, 177-187, May 2014.
doi:10.1016/j.rser.2014.01.087        Google Scholar

8. Kharkovsky, S. and R. Zoughi, "Microwave and millimeter wave nondestructive testing and evaluation — Overview and recent advances," IEEE Instrumentation & Measurement Magazine, Vol. 10, No. 2, 26-38, April 2007.
doi:10.1109/MIM.2007.364985        Google Scholar

9. Zhu, Y.-K., G.-Y. Tian, R.-S. Lu, and H. Zhang, "A review of optical NDT technologies," Sensors, Vol. 11, No. 12, 7773-7798, August 2011.
doi:10.3390/s110807773        Google Scholar

10. Li, Z., A. Haigh, C. Soutis, A. Gibson, and R. Sloan, "Microwaves sensor for wind turbine blade inspection," Applied Composite Materials, November 2016.        Google Scholar

11. Fukasawa, R., "Terahertz imaging: Widespread industrial application in non-destructive inspection and chemical analysis," IEEE Transactions on Terahertz Science and Technology, Vol. 5, No. 6, 1121-1127, 2015.        Google Scholar

12. Wetzel, K., K. Lee, A. Tran, B. Stakenborghs, and R. J. Woodward, "Volumetric inspection of wind turbine blades using a microwave interferometric technique," Materials Evaluation, 477-484, 2016.        Google Scholar

13. Ghasr, M. T., M. J. Horst, M. R. Dvorsky, and R. Zoughi, "Wideband microwave camera for real-time 3-D imaging," IEEE Transactions on Antennas and Propagation, Vol. 65, No. 1, 258-268, January 2017.
doi:10.1109/TAP.2016.2630598        Google Scholar

14. Hsu, D. K., K.-S. Lee, J.-W. Park, Y.-D. Woo, and K.-H. Im, "NDE inspection of terahertz waves in wind turbine composites," International Journal of Precision Engineering and Manufacturing, Vol. 13, No. 7, 1183-1189, July 2012.
doi:10.1007/s12541-012-0157-5        Google Scholar

15. Li, C., Z. Peng, T.-Y. Huang, T. Fan, F.-K. Wang, T.-S. Horng, J.-M. Munoz-Ferreras, R. GomezGarcia, L. Ran, and J. Lin, "A review on recent progress of portable short-range noncontact microwave radar systems," IEEE Transactions on Microwave Theory and Techniques, 1-15, 2017.        Google Scholar

16. Moll, J., P. Arnold, M. M¨alzer, V. Krozer, D. Pozdniakov, R. Salman, S. Rediske, M. Scholz, H. Friedmann, and A. Nuber, "Radar-based structural health monitoring of wind turbine blades: The case of damage detection," Structural Health Monitoring: An International Journal, 147592171772144, August 2017.
doi:10.1177/1475921717721447        Google Scholar

17. Arnold, P., J. Moll, M. Malzer, V. Krozer, D. Pozdniakov, R. Salman, S. Rediske, M. Scholz, H. Friedmann, and A. Nuber, "Radar-based structural health monitoring of wind turbine blades: The case of damage localization," Wind Energy, January 2018.        Google Scholar

18. Moll, J., V. Krozer, P. Arnold, M. D¨urr, R. Zimmermann, R. Salman, D. H¨ubsch, H. Friedmann, A. Nuber, M. Scholz, and P. Kraemer, "Radar-based structural health monitoring of wind turbine blades," 19th World Conference on Non-Destructive Testing, 1-8, Munich, Germany, 2016.        Google Scholar

19. Moll, J., M. Malzer, J. Simon, V. Krozer, M. Feulner, H. Friedmann, A. Nuber, R. Salman, D. Pozdniakov, and M. Durr, "Field demonstration of radar-based SHM of wind turbine blades at a 2 MW wind turbine: Installation, data acquisition and signal analysis," 11th International Workshop on Structural Health Monitoring, 1-8, Stanford, USA, 2017.        Google Scholar

20. Scholz, N., J. Moll, M. Malzer, K. Nagovitsyn, and V. Krozer, "Random bounce algorithm: realtime image processing for the detection of bats and birds: Algorithm description with application examples from a laboratory flight tunnel and a field test at an onshore wind energy plant," Signal, Image and Video Processing, Vol. 10, No. 8, 1449-1456, November 2016.
doi:10.1007/s11760-016-0951-0        Google Scholar

21. Moll, J. and V. Krozer, "Radar-based mechanical vibration sensing for structural health monitoring applications: A comparison of radar transceiver measurements at 24 GHz and 100 GHz," 8th European Workshop on Structural Health Monitoring, 1-6, 2016.        Google Scholar

22. Moll, J., M. Malzer, V. Krozer, D. Pozdniakov, R. Salman, J. M. Beetz, and M. Kossl, "Activity monitoring of bats in a laboratory flight tunnel using a 24 GHz FMCW radar system," 11th European Conference on Antennas and Propagation, 2541-2545, Paris, France, 2017.        Google Scholar

23. Soumekh, M., Synthetic Aperture Radar Signal Processing with MATLAB Algorithms, Wiley, 1999.

24. Sakamoto, T., T. Sato, P. Aubry, and A. Yarovoy, "Frequency-domain Kirchhoff migration for near-field radar imaging," IEEE Conference on Antenna Measurements & Applications, 1-4, 2015.        Google Scholar

25. Sakamoto, T., T. Sato, P. J. Aubry, and A. G. Yarovoy, "Ultra-wideband radar imaging using a hybrid of kirchhoff migration and stolt F-K migration with an inverse boundary scattering transform," IEEE Transactions on Antennas and Propagation, Vol. 63, No. 8, 3502-3512, 2015.
doi:10.1109/TAP.2015.2431725        Google Scholar

26. Zhuge, X. and A. G. Yarovoy, "Three-dimensional near-field MIMO array imaging using range migration techniques," IEEE Transactions on Image Processing, Vol. 21, No. 6, 3026-3033, 2012.
doi:10.1109/TIP.2012.2188036        Google Scholar

27. Gorham, L. A. and L. J. Moore, "SAR image formation toolbox for MATLAB,", 769906-769906-13, April 2010.        Google Scholar

28. Arnold, P., J. Moll, and V. Krozer, "Design of a sparse antenna array for radar-based structural health monitoring of wind turbine blades," IET Radar, Sonar & Navigation, Vol. 11, No. 8, 1259-1265, August 2017.
doi:10.1049/iet-rsn.2016.0355        Google Scholar