Radio-Frequency Sensors for Nondestructive Evaluation of Materials

Abstract:

We report several radio-frequency (RF) sensors for possible use in material NDE and process control: an ultra-wide band (UWB) impulse sensor and microwave and millimeter-wave stepped-frequency sensors. The UWB sensor generates ultra-short pulses directly while the stepped-frequency sensors produce ultra-short pulses indirectly through pulse-synthesis. Ultra-short pulses possess ultra-wide bandwidths and have uniquely desirable characteristics such as fine resolution and high accuracy for material assessment. The UWB impulse sensor operates over multiple pulse durations from 450 to 1170 ps with 5.5-GHz RF bandwidth. It performs well through tests of various samples, demonstrating its usefulness for sensing. The microwave stepped-frequency sensor operates from 0.6 to 5.6 GHz and the millimeter-wave stepped-frequency sensor operates from 29.72-37.7 GHz. They have demonstrated abilities in surface and near-surface sensing of various structures. These developed compact RF sensors are attractive for NDE and process control of materials and various other sensing applications.

• Periodical: Advanced Materials Research (Volume 747)
• Pages: 765-768
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.747.765
• Online since: August 2013
• Authors: Joong Suk Park, Jeong Woo Han, Cam Nguyen
• Keywords: NDE, Nondestructive Evaluation, RF Sensor

References

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