| 摘要 |
Receiver comprising an RF input filter including a digitally controlled capacitor bank (Cb) with n capacitors being controlled by a tuning control signal (Vtune) for varying the tuning frequency of the RF input filter within a tuning range. For an improvement of the receiver in price/performance ratio the n capacitors of the digitally controlled capacitor bank (Cb) are monolithically integrated, whereas the bandwidth of the tuneable RF input filter is being adjusted to the maximum relative spread of said capacitors. A continuous tuning control signal (Vtune) is being supplied through an analogue to digital converter (A/D) to said capacitor bank (Cb) and to a first input of a differential stage (DS), an output of the analogue to digital converter (A/D) being coupled through a digital to analogue converter (D/A) to a second input of a differential stage (DS), an output of the differential stage (DS) being coupled to a control terminal of a variable capacitance diode (D) being arranged in parallel to the digitally controlled capacitor bank (Cb). <IMAGE>
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