The modulation of the carrier frequ

The modulation of the carrier frequency is designed by using GFSK for the baseband modulation. This is because GFSK narrows the width of the baseband pulses. The Pass-band modulation employs FHSS technique in order to provide security due to the generation of a pseudorandom carrier signal. The band pass is modulated using a Gaussian low pass filter and the degree of filtering is expressed by multiplying the filter’s 3dB bandwidth by the bit period which is called the BT product. As BT is lowered the amount of inter-symbol interference introduced increases because the symbol width becomes broader. In this design a BT equivalent to 0.5 is utilised which makes it fit efficiently into a smaller frequency band. For that matter representing a digital one and zero will fit into a small frequency band. The impulse response of the Gaussian filter is provided as follows [8].