Linear frequency modulation interference suppressing in DSSS system based on BFT and FRFT
Hui Zhou · Journal of Communications · 2010
A fast approach to BFT (bi-orthogonal Fourier transform) was proposed, which transforms BFT to the product of the constants and discrete moments with Taylor series expansion, after the computational complexity of BFT was dis-cussed. A method of multicomponent LFM interference suppression in DSSS was introduced. First the received signal is transformed by BFT, thus the value of every chirp ratio is estimated by peak-searching in the BFT domain,and the corresponding rotational angles of FRFT can be figured out from these values.Then the interference in fractal domain is excised by serial filters. Discussion and numerical simulation results show the validity of this method.In addition,when compared with other two-dimension time-frequency filtering algorithms,it reduces computational complexity with no loss of BER performance.