| 摘要 |
<p>A method is provided for remote detection of objects, where an individual object (20) is provided with at least one sensor (30) comprising at least one magnetic element (31-34) representing an identity of the sensor. A first electromagnetic signal (50) is generated for exciting the or each magnetic element to produce a second electromagnetic signal (60), an amplitude of which is modulated by a magnetic field (Hmod). A reply signal (80) is produced by demodulating the second electromagnetic signal (60, 70). A variation in amplitude of the reply signal is detected in response to a variation in amplitude of the magnetic field (Hmod), and the detected variation in amplitude is used for determining a geometric property, such as the length, of the or each magnetic element (31-34). An identity of the sensor (30) is determined from the geometric property.</p> |
