Passive sensors, wireless sensor systems, and the measurement method of the wireless sensor system

摘要

Even if there are individual differences due to manufacturing variations or the like of the sensor element, I realize the wireless sensor system that can obtain high measurement accuracy. Passive sensors (10), and a (13) and the identification mark (12) SAW resonators. Is a mark corresponding to the identification information group (Gr) (13) for identification mark. The base unit (20), sends an excitation signal (SpL) to (10) a passive sensor to receive the resonant signal SAW resonator (12) and (Sfp), to obtain (fp) resonance frequency. It also reads the (13) the identification mark, the master unit (20) acquires the identification information group (Gr). Magnetic strength identifying group information resonance signal (fp), identifying group information (Gr), is stored in advance and the (Gr) each base unit (20), - the frequency characteristic, based on, for calculating the magnetic strength.