Title :
Fast blind decision feedback equalizer for mobile links with short blocks
Author :
Schmidbauer, Andreas ; Schmatutz, M. ; Herzog, Rupert
Author_Institution :
Inst. for Commun. Eng., Munich Univ. of Technol., Germany
Abstract :
An adaptive algorithm for a blind decision feedback equalizer (DFE) is presented. It is derived from a linear algorithm for blind equalization, the super-exponential algorithm (Supex) introduced by Shalvi and Weinstein (1993) which uses a FIR-filter to approximate the MMSE (minimum mean square error) solution. However there are severe problems for a linear equalizer if zeros of the channel impulse response are on or close to the unit circle as it is likely in mobile radio channels. Then the MMSE solution becomes singular, respectively a large number of filter coefficients are necessary. A nonlinear filter structure like the DFE can handle this problem. We compare also the convergence properties of the Supex and the blind DFE
Keywords :
AWGN; adaptive equalisers; blind equalisers; convergence of numerical methods; decision feedback equalisers; land mobile radio; least mean squares methods; nonlinear filters; poles and zeros; transient response; AWGN; DFE; FIR-filter; MMSE; Supex; adaptive algorithm; additive white Gaussian noise; blind decision feedback equalizer; channel impulse response; convergence properties; fast blind decision feedback equalizer; filter coefficients; linear algorithm; linear equalizer; minimum mean square error; mobile links; mobile radio fading channel; nonlinear filter structure; short blocks; singular solution; super-exponential algorithm; unit circle; zeros; Adaptive algorithm; Blind equalizers; Convergence; Decision feedback equalizers; Digital communication; Land mobile radio; Mean square error methods; Mobile communication; Nonlinear filters; Power system modeling;
Conference_Titel :
Vehicular Technology Conference, 1998. VTC 98. 48th IEEE
Conference_Location :
Ottawa, Ont.
Print_ISBN :
0-7803-4320-4
DOI :
10.1109/VETEC.1998.686188
