Abstract: This paper presents a new method for demodulating the frequency shift Keying (FSK) signals, the adaptive demodulation (ADEM) method. The commonly used least mean square (LMS) error adaptive filtering algorithm is employed for studying the demodulating procedure and the performance of the ADEM scheme. It is indicated by simulation experiments that the ADEM has many advantages over conventional ones, such as the powerful anti-noise ability,the small transfer delay, and the convenient implementation with DSP technology. The idea and Principle of the ADEM can also be applied to other modulation modes.

Key words: adaptive signal proceeding, digital communications, modulation and demodulation, computer simulation