Precise and fast frequency determination of resonant SAW sensors by a low-cost Six-Port interferometer

Start Page
1
End Page
5
Article Number
7520390
Citation
IEEE Instrumentation and Measurement Technology Conference: 7520390 (2016-07-22)
Contribution to Conference
IEEE Instrumentation and Measurement Technology Conference, 2016  
Publisher DOI
10.1109/I2MTC.2016.7520390
Surface acoustic wave (SAW) resonators are used for a broad range of wireless sensing applications, some of them having high demands on the resolution as well as the measurement update rate. This paper presents a new interrogation method for precise and fast frequency determination of passive SAW resonators based on instantaneous frequency measurement (IFM) by a low-cost Six-Port interferometer. By using a delay line, the frequency measurement is reduced to a phase measurement that can be instantaneously evaluated by the Six-Port network. No complex signal processing is necessary providing high update rates and low hardware costs. A demonstrator in the 2.4 GHz frequency band shows the feasibility and the precision of the concept with measurement times of only a few microseconds.
DDC Class
000: Allgemeines, Wissenschaft