Title :
Locally passive hybrid sensing tags based on flexible substrates and surface acoustic wave devices
Author :
Ho, H. ; Chu, E. ; Forman, M.A. ; Skinner, J.L.
Author_Institution :
Sandia Nat. Labs., Livermore, CA, USA
Abstract :
This paper describes the integration of surface acoustic wave (SAW) filters, microfabricated transmission lines, and sensors onto polymer substrates to enable a passive wireless sensor platform. Incident microwave pulses on the integrated antenna are converted to an acoustic wave via the SAW filter and transmitted to a notional impedance-based sensor, which for this work is a photodiode. Changes in sensor state induce a corresponding change in impedance resulting in a reflectance profile. Data collected at a calibrated receiver can be used to infer the state of the sensor. Based on this principle, light flux intensity is wirelessly sensed at distances up to 3.6 m.
Keywords :
microfabrication; photodiodes; polymers; substrates; surface acoustic wave filters; surface acoustic wave sensors; transmission lines; wireless sensor networks; Incident microwave pulses; SAW filter; flexible substrates; impedance-based sensor; light flux intensity; locally passive hybrid sensing tags; microfabricated transmission lines; passive wireless sensor platform; photodiode; polymer substrates; surface acoustic wave devices; surface acoustic wave filters; Acoustic sensors; Acoustic waves; Microwave devices; Microwave filters; Passive filters; Polymers; Sensor phenomena and characterization; Surface acoustic wave devices; Surface acoustic waves; Wireless sensor networks; Flexible Substrate; Passive Wireless Sensing; SAW Sensor;
Conference_Titel :
Solid-State Sensors, Actuators and Microsystems Conference, 2009. TRANSDUCERS 2009. International
Conference_Location :
Denver, CO
Print_ISBN :
978-1-4244-4190-7
Electronic_ISBN :
978-1-4244-4193-8
DOI :
10.1109/SENSOR.2009.5285707