APPARATUS AND METHOD FOR DEMODULATING AN INPUT SIGNAL

摘要

The invention relates to an apparatus (300; 400; 500; 600) for demodulating an input signal (306; 402; 520), comprising a frequency detector (302; 403; 502.1,..., 502. N; 603) for tracking a frequency (f2; fd1,..., fdN) of the input signal (306; 402; 520), an oscillator (304; 410; 505; 605, 606) and a mixer (305; 408; 507; 608, 609), wherein the input signal (306; 402; 520) and an output signal (307; 409) of the oscillator (304; 410; 505; 605, 606) constitute the incoming signals for the mixer (305; 408; 507; 608, 609) and the output signal of the mixer (305; 408; 507; 608, 609) constitutes the demodulated input signal, wherein an arithmetic unit (303; 404; 504; 604) is arranged downstream of the frequency detector (302; 403; 502.1,..., 502. N; 603) and upstream of the oscillator (304; 410; 505; 605, 606), wherein the tracked frequency (f2; fd1,..., fdN) of the input signal (306; 402; 520) and a predefined second frequency (f1; faux1,..., fauxM) constitute the incoming signals of the arithmetic unit (303; 404; 504; 604) and the arithmetic unit (303; 404; 504; 604) is designed such that it computes a control signal (f3; f4; fo1,..., foP) for the oscillator (304; 410; 505; 605, 606) from the tracked frequency (f2; fd1,..., fdN) of the input signal (306; 402; 520) and the predefined second frequency (f1; faux1,..., fauxM) with the output signal (307; 409) of the oscillator (304; 410; 505; 605, 606) depending on the control signal (f3; f4; fo1,..., foP). The invention furthermore relates to a method for demodulating an input signal (306; 402; 520) with such an apparatus (300; 400; 500; 600).