Model-based implementation for the calculation of Power Spectral Density in an FPGA system

Cognitive Radio (CR) systems equipped with a spectrum sensing unit are able to access the radio frequency spectrum in a dynamic manner. This paper presents a model-based design approach and implementation for the calculation of the Power Spectral Density (PSD) of the received signal in a spectrum scanner. Design parameters based on the requirements of the complete CR system as well as the signal processing steps for the PSD calculation are described. The signal processing comprises the implementation of a control unit, selectable window functions, the Fast Fourier Transformation, the calculation of the magnitude, selectable number of averages for the calculation of peak and mean power values as well as the logarithmic representation of the spectrum. The presented processing block is integrated as part of an embedded system in an FPGA. The simulation and measurement results demonstrate and proof the functionality of the developed block with the shown design flow.