| 摘要 |
The invention relates to a method and to an arrangement for demodulating a signal (f) preferably frequency modulated with digital information, and then particularly a frequency shift modulated signal, with a frequency counter detector (16) which directly produces a digital value representative of the instantaneous frequency of the frequency modulated signal. In order to obtain the lowest possible uncertainty in frequency detection at unchanged counter frequencies (fr), the frequency modulated signal is mixed down to a difference frequency (f3) which is insignificantly higher than the sampling frequency (fs) required to extract the modulation information from the instantaneous counter value (N2). The frequency counter detector begins a counting sequence during each of the periods of the difference frequency. |
