Abstract: To address the issue of civil aviation ground-based navigation equipment being interfered with in multiple frequency bands, this study conducts research on direction finding and positioning of multi-band interference signals. Based on the existing GNSS interference direction finding system developed by the laboratory research group, the measurable frequency bands are expanded, and a ground-based navigation band interference source direction finding and positioning system based on a dual-antenna switching array is designed and implemented. The system adopts three pairs of dual-antenna arrays with different spacings, which can quickly switch arrays according to the working frequency band to achieve cross-band interference direction finding. To ensure the direction finding accuracy and stability of the system, a dual-channel phase consistencycompensation algorithm based on self-calibration is proposed and implemented, which significantly reduces the direction finding errors caused by non-ideal hardware characteristics.Inan open experimental site, interference sources are set to transmit different types of interference signals within multiple ground-based navigation frequency bands. Experimental tests show that the system has reliable positioning capability and good stability, which is of great significance for building a more robust civil aviation navigation anti-interference system.