Title :
2.45 GHZ Saw-based passive binary transponder for wireless interfaces of integrated sensors
Author :
Kuypers, Jan H. ; Tanaka, Shuji ; Esashi, Masayoshi
Author_Institution :
Tohoku Univ., Sendai
Abstract :
This paper describes the development of a MEMS tunable surface acoustic wave (SAW) device that allows an integrated sensor to be interrogated wirelessly in a range of several meters. The component itself requires no power for the wireless communication, as the principle is based on evaluating the reflected signal similar to a radar echo. The structure is similar to a one port reflective SAW delay line device. A MEMS switch is used to modulate the SAW according to the binary sensor output. The encoding solely requires an electrostatic tuning voltage of as low as 3 V for the MEMS switch. We successfully demonstrated that the device assembled on a microstrip antenna wirelessly transmitted ASCII characters over a distance of up to 2 m.
Keywords :
UHF devices; circuit tuning; electrostatic devices; microstrip antennas; microswitches; surface acoustic wave delay lines; transponders; wireless sensor networks; ASCII characters; MEMS switch fabrication; MEMS tunable surface acoustic wave device; SAW-based passive binary transponder; binary sensor output; electrostatic tuning voltage; frequency 2.45 GHz; integrated sensors; microstrip antenna; one port reflective SAW delay line device; reflected signal evaluation; wireless communication; wireless interfaces; wireless sensor technology; Acoustic sensors; Acoustic waves; Micromechanical devices; Microstrip antennas; Microswitches; Sensor phenomena and characterization; Surface acoustic wave devices; Surface acoustic waves; Transponders; Wireless sensor networks;
Conference_Titel :
Micro Electro Mechanical Systems, 2008. MEMS 2008. IEEE 21st International Conference on
Conference_Location :
Tucson, AZ
Print_ISBN :
978-1-4244-1792-6
Electronic_ISBN :
1084-6999
DOI :
10.1109/MEMSYS.2008.4443837