High-rate DFT-based data manipulator (HDDM) algorithm for effective interference mitigation

Interferences to global navigation satellite system (GNSS) signals are a significant threat to navigation security and reliability. Therefore, there is a continuous need to improve the robustness of receivers through the use of adequate interference mitigation methods. This paper presents the high-rate DFT-based data manipulator (HDDM) algorithm as a robust and efficient interference mitigation method. This method uses a discrete Fourier transform (DFT) to transform the signal to the Fourier domain, to remove strong signal components before transforming back to the time domain. What distinguishes this algorithm from many similar mitigation methods, that also deploy a DFT, is that the DFT is calculated for every sample delay. Thereby highly over-sampling the signal, which allows mitigation to remove an interference without causing distortion effects. Results have shown that the HDDM can potentially provide superior interference mitigation capabilities against frequency-modulated continuous-wave (FMCW) signals, compared to other commonly used mitigation algorithms. Further, the algorithm is suitable for hardware implementations, due to relatively low latency, low memory, and low tuning requirements. The HDDM is an improvement on other multi-spectral techniques, and allows robust and reliable interference removal.