Development of wireless, batteryfree gyroscope based on one-port SAW delay line and double resonant antenna

• Published in: Sensors and actuators. A. Physical. Vol. 220; pp. 270 - 280
• Main Authors: Fu, Chen, Elmazria, Omar, Sarry, Frédéric, Mahalingam, Thaiyan, Yang, Sang Sik, Lee, Keekeun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2014; Elsevier
• Subjects: Acoustics; Coriolis force; Double resonant antenna; Engineering Sciences; Materials; Micro and nanotechnologies; Microelectronics; Microgyrosensor; One-port SAW reflective delay line; Surface acoustic wave (SAW); Surface acoustic wave (SAW); Microgyrosensor; Double resonant antenna; One-port SAW reflective delay line; Coriolis force
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2014.10.006

•Batteryless, wireless SAW-based gyroscope implemented by using one-port SAW reflective delay line.•Two SAW sensors wirelessly activated by a single antenna with double resonant frequencies.•High sensitivity and mechanical robustness demonstrated under shock and vibrant environments.•Optimal device designs obtained by COM modeling. A wireless, battery-free micro-gyroscope was developed by employing a one-port surface acoustic wave (SAW) reflective delay line, a SAW resonator, and an antenna. Two SAW devices with different center frequencies were simultaneously activated by a single antenna with double resonant frequencies. An 80MHz RF energy from antenna activates a double-port SAW resonator while a 195MHz RF energy activates a one-port SAW delay line. The fabricated gyroscope showed clear reflection peaks with high signal-to-noise (S/N) ratios in both the time and frequency domains in measurement system during wireless testing. Upon rotation of the device, large shifts of the reflection peaks were observed owing to a secondary wave interference effect caused by the Coriolis force that depends on the spinning rate. The measured sensitivity and linearity of the developed gyroscope were, respectively, 1.35deg/(deg/s) and 0.91, which are promising values for our targeted applications. The temperature, metal mass effect, and vibration/shock effects were also studied and the results are discussed.