Patent ID: 6615029
Filing Date: 2003-09-02
Classification: H03D

Abstract:
A method for the demodulation of fm signals, the fm signals comprising a wanted carrier signal and an interfering carrier signal, the method comprising the steps of: generating a first signal (v3), said first signal (v3) being a function of the ratio (m) of the interfering carrier to the wanted carrier and of the instantaneous difference (&ohgr;d) between the frequency of the wanted carrier and the interfering carrier; generating a second signal (v4) from said first signal (v3) by removing any dc value from said first signal (v3); generating the mathematical square (v5) of said second signal (v4); generating a dc value (v6) from said squared signal (v5); generating a numerator function (v9) being a function of said dc value (v6), said second signal (v4) and a dc offset (v7); generating a denominator function (v8) being a function of said first signal (v3) and said dc offset (v7); performing a division process between said numerator function (v9) and said denominator function (v8) to generate a quotient function (v10); and using said quotient function (v10) to control a demodulator circuit to generate a desired output.