title: Distortion analysis of subband adaptive filtering methods for FMRI active noise control systems.
abstract: Delayless subband filtering structure, as a high performance frequency domain filtering technique, is used for canceling broadband fMRI noise (8 kHz bandwidth). In this method, adaptive filtering is done in subbands and the coefficients of the main canceling filter are computed by stacking the subband weights together. There are two types of stacking methods called FFT and FFT-2. In this paper, we analyze the distortion introduced by these two stacking methods. The effect of the stacking distortion on the performance of different adaptive filters in FXLMS algorithm with non-minimum phase secondary path is explored. The investigation is done for different adaptive algorithms (nLMS, APA and RLS), different weight stacking methods, and different number of subbands.
authors.affiliation: Department of Electrical Engineering, University of Texas at Dallas, Richardson, USA. ali.a.milani@student.utdallas.edu
authors.forename: Ali A
authors.initials: AA
authors.lastname: Milani
authors.forename: Issa M
authors.initials: IM
authors.lastname: Panahi
authors.forename: Richard
authors.initials: R
authors.lastname: Briggs
mesh_terms: D000465:Algorithms; D016477:Artifacts; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted