| 摘要 |
The invention relates to a method and an apparatus intended to measure the impedance of a resonant sensor with logarithmic response. According to the invention, the method comprises the passive interrogation of a resonant sensor (1) about the series-parallel resonance frequency or a harmonic of the natural frequency, by means of an attenuator (2), using a signal from a generator (3), controlled by a microcontroller (4), while the signals from some voltage and current probes (5 and 6) are applied to some logarithmic detection circuits (7 and 8), followed by an analogue processing unit (9) at the output of which a voltage proportional with the logarithm of the impedance of the resonant sensor (1) is obtained, said voltage being then applied to the input of an analogue-to-digital convertor (10) controlled by the microcontroller (4). |
