| 摘要 |
The electronic circuit which is intended to feed a magnetic-field sending coil has a first input terminal (1) for receiving a power-supply voltage (Ubat), a second input terminal (2) for receiving a periodic control signal (SC) within a predefined frequency range, an output terminal (4) for generating an output current (I) in the said sending coil (L) connected between the said output terminal (4) and earth (M), in such a way as to convert the said periodic control signal into a periodic magnetic field sent out by the coil. In this circuit, a series RLC circuit (RLC1) is connected between the said output terminal (4) and earth in order to form a tuned antenna with the sending coil (L). Such a configuration makes it possible to send out a magnetic field according to an extended pattern so that a receiver unit has a better sensitivity.
|
