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Stephan Weiss1, Markus Rupp2, and Lajos Hanzo1 1 Dept. Ele troni s & Computer S ien e, University of Southampton, UK 2 Wireless Resear h Lab / Bell-Labs, Lu ent Te hnologies, Holmdel, NJ, USA fsw1,lhg e s.soton.a .uk, rupp lu ent. om Abstra t In this paper we proposed a modi ation of the " lassi " fra tionally spa ed de ision feedba k equaliser (FSDFE) in order to in rease the slow onvergen e rate of the oversampled feed-forward se tion for LMS type algorithms. This is performed by employing a subband stru ture for the latter part of the FS-DFE, whi h results in a de orrelation of the input. We motivate why an oversampled subband de omposition is bene ial and omment on the sele tion of the lter banks. As an additional bene t, omputational savings arise if judiious implementation of the lter banks is ombined with the internal de imation and expansion operations in the FS-DFE. Simulations for a sever multipath environment are presented. 1. Introdu tion Fra tionally spa ed de ision feedba k equalisers (FS-DFE) based on LMS-type algorithms have re ently been shown to exhibit onsiderably slower onvergen e than their symbol-spa ed ounterparts, parti ularly at high SNR [1℄. This has been attributed to large eigenvalue spread of the equaliser's input signal. Sin e parti ularly in the area of broadband radio and TV over xed wireless hannels e orts go toward longer equalisation lters with additionally inhibited onvergen e speed, improvements of the onvergen e rate are generally desirable. The main task of the equaliser is to retrieve a transmitted signal u[n℄ from a distorted re eived opy x[n℄ at the output of a hannel [n℄, as given in Fig. 1. The