USA flag logo/image

An Official Website of the United States Government

Unpowered Wireless Ultrasound Generation and Sensing for Structural Health…

Award Information

National Aeronautics and Space Administration
Award ID:
Program Year/Program:
2012 / SBIR
Agency Tracking Number:
Solicitation Year:
Solicitation Topic Code:
Solicitation Number:
Small Business Information
9700 Great Seneca Highway Rockville, MD -
View profile »
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Phase 1
Fiscal Year: 2012
Title: Unpowered Wireless Ultrasound Generation and Sensing for Structural Health Monitoring of Composites
Agency: NASA
Contract: NNX12CF04P
Award Amount: $125,000.00


Damage detection based on ultrasonic waves is one of the most popular inspection schemes employed by many structural health monitoring (SHM) systems. We propose a novel unpowered wireless ultrasound generation and sensing system for SHM. Since ultrasonic signals generally have a frequency of a few tens of kilohertz to a few megahertz, they cannot be easily transmitted using a wireless means because of high sampling and high bandwidth requirements. Our system uses a frequency mixer to up-convert the ultrasonic signal to microwave frequency so that it can be transmitted wirelessly using a small antenna and down-convert the ultrasonic signal back to its original frequency once the wireless signal is received. Because the mixing of the ultrasound and the microwave signal is performed using a passive microwave component, i.e. a frequency mixer, the wireless sensor nodes do not need any local power. For ultrasound generation, an ultrasound-modulated signal is transmitted to a remote ultrasound generator, the generator recovers the ultrasound excitation signal using down conversion and supply it to a piezoelectric actuator. Since the sensing and generating nodes have the same configuration, each node can either act as a generator or a sensor. Sensor array can also be implemented. Compared to SAW sensor, our approach requires smaller antenna and achieves longer distance between interrogation unit and the sensor. Another key difference is that SAW sensor requires special piezoelectric substrate whereas our approach can use any piezoelectric sensor. Finally, the proposed approach is compatible with previous works on ultrasound-based technology. Previously developed knowledge on data processing and feature extraction can be easily adopted.

Principal Investigator:

Chiman Kwan
Principal Investigator

Business Contact:

Chiman Kwan
Business Official
Small Business Information at Submission:

Signal Processing, Inc.
13619 Valley Oak Circle ROCKVILLE, MD -

EIN/Tax ID: 134320631
Number of Employees:
Woman-Owned: Yes
Minority-Owned: Yes
HUBZone-Owned: No