Adaptive IIR notch filter with controlled bandwidth for narrow-band interference suppression in DS CDMA system

Author

Muuma, A. ; Nishimura, Shotaro ; Hinamoto, Takao

Author_Institution

Graduate Sch. of Eng., Hiroshima Univ., Japan

Volume

4

fYear

2003

fDate

25-28 May 2003

Abstract

Suppression of NBI in a DS CDMA system using a fully adaptive IIR notch filter is investigated. An algorithm that requires no gradient signal generating filters for tracking the center frequency of the NBI is proposed. A gradient algorithm for adapting the notch bandwidth coefficient to a value that results in maximum SNR improvement factor and minimum BER is presented. Convergence behaviors of the algorithms are analyzed. Closed-form expressions for SNR improvement factor and BER of the system are derived. Simulations are shown to verify the analyses and compare the performance of the proposed scheme with that of a linear adaptive FIR prediction filter.

Keywords

IIR filters; adaptive filters; code division multiple access; error statistics; interference suppression; notch filters; spread spectrum communication; DS CDMA system; NBI center frequency tracking; NBI suppression; adaptive IIR notch filter; algorithm convergence behaviors; controlled bandwidth; gradient algorithm; gradient signal generating filters; linear adaptive FIR prediction filter; maximum SNR improvement factor; minimum BER; narrow-band interference suppression; notch bandwidth coefficient; Adaptive control; Adaptive filters; Bandwidth; Control systems; Finite impulse response filter; IIR filters; Interference suppression; Multiaccess communication; Narrowband; Programmable control;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems, 2003. ISCAS '03. Proceedings of the 2003 International Symposium on

Print_ISBN

0-7803-7761-3

Type

conf

DOI

10.1109/ISCAS.2003.1205848

Filename

1205848