Abstract:

To mitigate the deleterious influence of distance measure equipment (DME) impulse interference on the orthogonal frequency division multiplexing (OFDM) receiver of L-band digital aeronautical communications system 1(L-DACS1) operating as an inlay system, a new interference suppression receiver for the L-DACS1 system is proposed based on jointing the subspace projection and the blind adaptive beam forming algorithm. Firstly, the subspace projection algorithm is used to suppress the strong DME interference by projecting the array received signals on the orthogonal complement space of interferences. Then, the blind adaptive beam forming algorithm is proposed to extract the OFDM direct path signals based on inner product maximization criterion between the desired and reference signals. Computer simulation results show that the proposed OFDM receiver can effectively suppress the strong DME impulse interference and OFDM scattering signal and improve the reliability of the L-DACS1 system.