An Improved Approach of SFAP Algorithm for Suppressing Concurrent Narrowband and Wideband Interference

Anti-jamming algorithm of Space-Frequency Adaptive Processing (SFAP) will fail when plural narrowband jammers in diverse directions fall into the same subfrequency band and the number of jammers exceeds the limitation that an antenna array can cope with. A well-known method called frequency excision was proposed to add into SFAP to remove these narrowband jammers. However, it is possible that narrowband interference cannot be detected correctly due to the existence of wideband interference. In such situation, this method becomes inapplicable. In this paper, a new approach of SFAP is proposed to cope with concurrent narrow and wideband jammers. It determines the weights of each sub-band based on the data from itself and adjacent sub-bands. Computer simulation with an antenna model of four elements in Y-form shows that the proposed approach improves the performance of SFAP significantly under concurrent narrow and wideband jammers and the increased implementation cost of the new approach is very small and can be negligible.