at Google ScholarTitle data
Fischerauer, Gerhard ; Dickert, Franz Ludwig ; Sikorski, Renatus:
Telemetric surface acoustic wave chemical sensors.
In:
Proceedings of the 1998 IEEE International Frequency Control Symposium. -
Piscataway, NJ
: IEEE
,
1998
. - pp. 608-614
ISBN 0-7803-4373-5
DOI: https://doi.org/10.1109/FREQ.1998.717963
Abstract in another language
The present paper deals with surface acoustic wave (SAW) chemical sensors that operate without power supply and can be read wirelessly by electromagnetic interrogation signals. These novel chemical sensors are based on the well-known SAW identification (ID) tag principle with a sensitive coating applied to the device surface. It is shown that a gas detection limit of a few ppm to some hundred ppm requires a reflector time distance of several microseconds, corresponding to a spatial distance of typically 10 mm. This relatively large device geometry places an upper limit on the additional insertion attenuation caused by the sensitive layer and restricts the possible coating materials. As a practical demonstration, we have designed and investigated a humidity sensor at 433.92 MHz a frequency band allotted to industrial, scientific, and medical apparatus in Germany. The measured return loss without sensitive layer was between 20 and 25 dB. A coating of cross-linked polyvinyl alcohol served as sensitive layer, the thickness of which was kept at 3 to 10 nm. With these devices, relative humidity changes of a few percent are detected quite easily. This illustrates the fact that telemetric SAW chemical sensors can actually be realized.
Further data
| Item Type: | Article in a book |
|---|---|
| Refereed: | No |
| Keywords: | Chemical sensors; humidity sensors; SAW; ID tag; telemetry; ISM band |
| Institutions of the University: | Faculties > Faculty of Engineering Science > Chair Measurement and Control Technology > Chair Measurement and Control Technology - Univ.-Prof. Dr.-Ing. Gerhard Fischerauer |
| Result of work at the UBT: | No |
| DDC Subjects: | 600 Technology, medicine, applied sciences > 620 Engineering |
| Date Deposited: | 22 Jul 2024 12:41 |
| Last Modified: | 22 Jul 2024 12:41 |
| URI: | https://eref.uni-bayreuth.de/id/eprint/90020 |