Implementation of RF signal generator for demodulator/receiver testing in SDR design

In this paper, the design of a RF signal generator for demodulator/receiver testing is presented. The design is based on direct digital synthesizer (DDS) controlled by microprocessor. This module provides arbitrary waveform signal generation up to 400 MHz. Output signal level is adjustable by digitally controlled attenuator. Dynamic range of RF test signal generator is 130 dB. Frequency shift keying and amplitude shift keying are performed with pseudo random modulating signal and measurement results are provided.