Title :
Rejection of narrowband interference in DS spread spectrum systems using two-stage decision feedback filters
Author :
Dukic, Miroslav L. ; Jevic, Zoran S Dobrosavl ; Stojanovic, Z.D. ; Stojanovic, I.S.
Author_Institution :
Fac. of Electr. Eng., Belgrade Univ., Serbia
Abstract :
The further improvement of the direct sequence spread spectrum (DSSS) receiver proposed by Dukic et al. (1990), using decision feedback (DFB) filter, in reducing the narrowband interference (NBI) is presented. In the first stage of this new receiver, the conventional demodulator is followed by a DFB filter, the role of which is to produce the NBI reference signal. The reference derived in this manner is the input signal to the two-sided adaptive transversal (AT) filter, this being used as a NBI rejection filter. The performance of such a receiver has been analyzed in term of the output error probability. The results obtained show that this two-stage DFB filter techniques enhance the immunity of the new DSSS receiver against NBI, relative to the previously reported receivers using linear and nonlinear NBI rejection methods
Keywords :
adaptive filters; circuit feedback; demodulators; filtering theory; interference suppression; probability; pseudonoise codes; radio receivers; radiofrequency interference; spread spectrum communication; DS spread spectrum systems; demodulator; direct sequence spread spectrum receiver; input signal; interference rejection filter; narrowband interference rejection; output error probability; reference signal; two-sided adaptive transversal filter; two-stage decision feedback filters; Adaptive filters; Demodulation; Error probability; Feedback; Interference; Narrowband; Nonlinear filters; Performance analysis; Spread spectrum communication; Transversal filters;
Conference_Titel :
Spread Spectrum Techniques and Applications, 1994. IEEE ISSSTA '94., IEEE Third International Symposium on
Conference_Location :
Oulu
Print_ISBN :
0-7803-1750-5
DOI :
10.1109/ISSSTA.1994.379530
