Title :
Finite-precision design and implementation of all-pass polyphase networks for echo cancellation in sub-bands
Author :
Tanrikulu, O. ; Baykal, B. ; Constantinides, A.G. ; Chambers, J.A. ; Naylor, P.A.
Author_Institution :
Dept. of Electr. Eng., Imperial Coll. of Sci., Technol. & Med., London, UK
Abstract :
All-pass polyphase networks (APN) are particularly attractive for acoustical echo cancellation (AEC) arranged in sub-bands. They provide lower inter-band aliasing, delay and computational complexity than their FIR counterparts. Moreover, APNs achieve higher echo return loss enhancement (ERLE) performance and faster convergence than full-band processing. In the paper, the finite precision implementation of APNs is addressed. A procedure is presented for re-optimising the all-pass coefficients of the prototype low-pass filter for finite precision operation. Robust finite precision implementation of a prototype low-pass filter is discussed. The results of a set of AEC experiments are reported with full and 16-bit precision implementation
Keywords :
IIR filters; acoustic signal processing; all-pass filters; antialiasing; computational complexity; convergence of numerical methods; delays; digital filters; echo suppression; low-pass filters; 16-bit precision implementation; all-pass coefficients; all-pass polyphase networks; computational complexity; convergence; delay; echo cancellation; echo return loss enhancement; finite precision operation; finite-precision design; implementation; inter-band aliasing; prototype low-pass filter; re-optimisation; robust finite precision implementation; sub-bands; Acoustical engineering; Attenuation; Computational complexity; Echo cancellers; Finite impulse response filter; IIR filters; Intelligent networks; Low pass filters; Prototypes; Signal synthesis;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 1995. ICASSP-95., 1995 International Conference on
Conference_Location :
Detroit, MI
Print_ISBN :
0-7803-2431-5
DOI :
10.1109/ICASSP.1995.479486
