A software-defined radio tool for interference analysis

A software defined radio based on the GNURadio (GR)[1][11] framework has been developed. The radio can be used for real-time receiving or transmitting of signals, or for simulating different scenarios. The radio combines native GR blocks with custom blocks and runtime-configurable flowgraph generation. The flowgraph can be defined and monitored using a comprehensive user interface (GUI), or from a JSON configuration file. The radio supports a wide range of waveforms from standard PSK to more unusual U/AQPSK and OQPSK. An integrated channel model includes effects of nonlinear power amplifier, phase noise, frequency offset, thermal noise, and Doppler. The GUI allows the user to quickly instantiate multiple instances of the SDR to study interaction between adjacent channels. Further, as waveforms get more complex and rely on powerful error correction, the effect of an adjacent channel interferer on a victim signal becomes more difficult to predict. The paper presents detailed block diagrams of the radio in different configurations.