QFSK RECEIVER

The Quadrature Frequency Shift Keying is not very commonly used technique of digital modulation in telecommunication systems. The receiver for Quadrature Frequency Shift Keying (QFSK) modulated wave is based on the technique of separation of the four different frequencies that make up the QFSK modulated signal.

Figure 1 shows various waveforms that lead to the final demodulated data signal.

Figure 1: Separating carrier frequencies from QFSK modulated signal

At the end of the experiment, students are encouraged to perform Quadrature frequency shift keying demodulation of QFSK modulated signals and observe the results on the oscilloscope.