Title :
Passive Temperature Sensing Tag for Sensor Networks
Author :
Kitayoshi, Hitoshi ; Sawaya, Kunio
Author_Institution :
Hatchery Square 7th R&D, Univ. of Tohoku, Sendai
Abstract :
A novel passive temperature sensing tag for a long reading range composed of a divided microstrip antenna and a rectifying circuit boosting the DC voltage is proposed. Experimental study of fabricated passive tag using varactor diodes, in which 30 m range response can be achieved in the 4 W EIRP reader at 860-960 MHz band, is described. Passive tags for temperature-monitoring system in the 4 W EIRP reader at 2.45 GHz band are also fabricated to demonstrate validity of proposed tags for a range longer than 9 m. The tags have sizes of 90 times 60 times 4 mm and 60 times 25 times 4 mm for 900 MHz and 2.45 GHz bands, respectively.
Keywords :
microstrip antennas; rectifying circuits; temperature sensors; varactors; wireless sensor networks; 4 W EIRP reader; distance 30 m; frequency 2.45 GHz; frequency 860 MHz to 960 MHz; microstrip antenna; passive tags; passive temperature sensing tag; rectifying circuit; sensor networks; temperature-monitoring system; varactor diodes; Diodes; Dipole antennas; Impedance; Microstrip antennas; Multiplying circuits; Radio frequency; Rectifying circuits; Temperature distribution; Temperature sensors; Voltage;
Conference_Titel :
Antennas, Propagation & EM Theory, 2006. ISAPE '06. 7th International Symposium on
Conference_Location :
Guilin
Print_ISBN :
1-4244-0162-3
Electronic_ISBN :
1-4244-0163-1
DOI :
10.1109/ISAPE.2006.353282
