In this paper a closed-form approximated expression is proposed for the Intersymbol Interference (ISI) as a function of time valid during the entire stages of the non-blind adaptive deconvolution process and is suitable for the noisy, real and two independent quadrature carrier input case. The obtained expression is applicable for type of channels where the resulting ISI as a function of time c...

An adaptive transversal equalizer based on the least-mean-square (LMS) algorithm, operating in an environment with a temporally correlated interference, can exhibit better steady-state mean-square-error (MSE) performance than the corresponding Wiener filter. This phenomenon is a result of the nonlinear nature of the LMS algorithm and is obscured by traditional analysis approaches that utilize t...

The recent digital transmission systems impose the application of channel equalizers with short training time and high tracking rate. Equalization techniques compensate for the time dispersion introduced by communication channels and combat the resulting inter-symbol interference (ISI) effect. Given a channel of unknown impulse response, the purpose of an adaptive equalizer is to operate on the...

This paper studies the behavior of the error sequence of stop-and-go variants of two adaptive blind equalizers, namely CMA2-2 and Sato’s algorithm. It is shown that for transmitted signals with constant modulus , the equalizer output can be made to lie within the circle of radius p c infinitely often, for some value of c that is only slightly larger than one.

For advanced mobile communication systems that adopt orthogonal frequency-division multiple access (OFDMA) technologies, intercarrier interference (ICI) significantly degrades performance when mobility is high. Standard specifications and concerns about complexity demand low-cost methods with deployment readiness and decent performance. In this paper, novel zero forcing (ZF) and minimum mean-sq...

Along with the advent of wireless mobile communications, blind equlizers are becoming a key component for systems that demand reliability and robustness. Central to the design of blind equalizers is the cost function that the adaptive lter algorithm minimizes. Mean-square errors are found no longer applicable as information-bearing source sequences are not available to blind equalizers. We beli...

ORTHOGONAL MULTIPLE CARRIER DATA TRANSMISSION Thomas Wiegand1 and Norbert J. Fliege2 1Telecommunications Institute University of Erlangen-Nuremberg Cauerstr. 7/NT, 91058 Erlangen, Germany [email protected] 2Telecommunications Institute Hamburg University of Technology Eissendorfer Str. 40, 21071 Hamburg, Germany [email protected] ABSTRACT Orthogonal multiple carrier d...

This paper describes a blind adaptive method for the dereverberation of speech/audio signals in a closed room environment based on the use of multiple microphones (two or more) by utilizing the second-order statistics of the reverberated speech signals only. The spatial diversity provided by the microphone array creates the equivalent of multiple channels, where each channel is the impulse resp...

We investigate underwater acoustic (UWA) channel equalization and introduce hierarchical and adaptive nonlinear channel equalization algorithms that are highly efficient and provide significantly improved bit error rate (BER) performance. Due to the high complexity of nonlinear equalizers and poor performance of linear ones, to equalize highly difficult underwater acoustic channels, we employ p...

This paper considers the problems of channel estimation and adaptive equalization in the novel framework of set-membership parameter estimation. Channel estimation using a class of set-membership identification algorithms known as optimal bounding ellipsoid (OBE) algorithms and their extension to track time-varying channels are described. Simulation results show that the OBE channel estimators ...