Detection of binary data for FSK digital modulation signals using spectrum estimation techniques

FSK is widely used for the transmission of data over passband channels due to the simplicity of implementation using noncoherent detection schemes. Better BER performance can be achieved with accurate phase synchronization using a coherent detection scheme. By using the fast Fourier transform (FFT), it is possible to implement spectrum based detection: complex sinusoid and complex square wave. The BER performance is slightly lower than coherent detection. Unlike coherent detection, phase synchronization is not critical for the spectrum based detection. Further simplification in hardware implementation is achievable using spectrum based detection (complex square wave), since the use of multipliers is not required.