Enhanced Spectrum Monitoring Capabilities Based on Software-Defined Radio Systems: Validation of a Real Time Frequency Hopping Signal Detection

This paper presents the development and validation of a frequency and channel detection application within GNU Radio, with a particular focus on improving the accuracy of Software Defined Radio (SDR) systems in monitoring frequency hopping signals. To test the application, a series of experimental scenarios were implemented using equipment such as a signal generator, a USRP N310 SDR platform, and a VHF wideband antenna. The scenarios included initial laboratory tests involving the generation of frequency hopping continuous wave signals in the 70-91 MHz range, followed by the generation of a 3G cellular standards-specific channel with sweep in the 70-90 MHz range, and a real frequency hopping test using military radio stations. The latter test was performed in the 75-85 MHz range using predefined frequencies (with 2 MHz steps between them) and different hopping rates (100 hops/s, 300 hops/s, 1000 hops/s). The goal of the in-situ tests was to evaluate the detection capabilities under different conditions. The results showed a 100% success rate in identifying and recording hopping frequencies. The results of this study confirm the reliability and effectiveness of the developed GNU Radio application and demonstrate the potential of the system itself for advanced telecommunications and spectrum management tasks in both the commercial and defense sectors.