The DME Interference Mitigation Based Wavelet Thresholding Algorithm for L-DACS Receiver

The L-DACS operates as an inlay system between two adjacent channels of the Distance Measuring Equipment (DME) system since the spectrum resources in the L-band are scarce and fragmented. This DME signal severely impacts the performance of L-DACS. This paper proposes an approach for mitigating DME interference by integrating spectrum aggregation technology and a wavelet thresholding algorithm. To enhance spectral efficiency, the method utilizes direct wideband aggregation technology at the transmission end to expand the bandwidth. Then, at the receiving end of Orthogonal Frequency Division Multiplexing (OFDM), the received signal is decomposed layer by layer using the wavelet threshold algorithm. The difference between the spectrum-aggregated signal and the DME signal in the wavelet domain is effectively identified to reconstruct the DME signal, thereby achieving interference elimination. Simulation results demonstrate that this method improves spectrum efficiency and data transmission rate while significantly mitigating DME interference, thereby enhancing the link transmission reliability of the L-DACS system.