Transmit and Receive of FM, SSB and DSD-AM, QPSK FSK Signals Using Softrock SDR and Matlab

Abstract

This study included the transmission and reception of FM signals using the Softrock Ensemble RXTX SDR transceiver and the Frequency Shıft Keyıng (FSK). FM signals are generated and plotted using MATLABalong with two input frequencies and a modulation index as inputs for the developed system, the DSB-SC modulated signals as well as DSB-WC signals are generated by multiplying the message with a carrier, while the SSB ones are generated by filtering out the lower sidebands of the DSB-SC modulated signal. Besides, the frequency modulation scheme in which digital information is transmitted through discrete frequency changes of a carrier wave. Advanced modulation and demodulation are fundamental procedures by computerized images that change into waveforms that are perfect with the qualities of a transmission channel; QPSK allows the signal to carry twice as much information as ordinary PSK using the same bandwidth.