An adaptive minimummean-square error (MMSE) array receiver based on the fuzzy-logic recursive least-squares (RLS) algorithm is developed for asynchronous DS-CDMA interference suppression in the presence of frequency-selective multipath fading. This receiver employs a fuzzy-logic control mechanism to perform the nonlinear mapping of the squared error and squared error variation, denoted by (e2,Δ...

The problem of asynchronous direct-sequence code-division multiple-access (DS-CDMA) detection over the ultra-wideband (UWB) multipath channel is considered. A joint synchronization, channel-estimation, and multiuser detection scheme based on the adaptive linear minimum mean square error (LMMSE) receiver is presented and evaluated. Further, a novel nonrecursive least-squares algorithm capable of...

This paper proposes an iterative maximum a posteriori probability (MAP) receiver for multiple-input-multiple-output (MIMO) and orthogonal frequency-division multiplexing (OFDM) mobile communications. For exploiting the space, time, and frequency diversity, the lowdensity parity-check code (LDPC) is used as a channel coding with a builtin interleaver. The receiver employs the expectation maximiz...

An adaptive filter is defined as a digital filter that has the capability of self adjusting its transfer function under the control of some optimizing algorithms. Most common optimizing algorithms are Least Mean Square (LMS) and Recursive Least Square (RLS). Although RLS algorithm perform superior to LMS algorithm, it has very high computational complexity so not useful in most of the practical...

This paper explores the potential of several popular equalization techniques and proposes new approaches to overcome their disadvantages. Such as the conventional least-mean-square (LMS ) algorithm, the recursive least-squares ( RLS ) algorithm, the filtered-X LMS algorithm and their development. An H 2 optimal initialization has been proposed to overcome the slow convergence problem while keep...

This paper presents a comparative performance study between the recently proposed time-varying LMS (TVLMS) algorithm and other two main adaptive approaches: the least-mean square (LMS) algorithm and the recursive leastsquares (RLS) algorithm. Three performance criteria are utilized in this study: the algorithm execution time, the minimum meansquared error (MSE), and the required filter order. T...

The conventional QR Decomposition Recursive Least Squares (QRD-RLS) method requires the order of X 2 multiplications-O[1\,JJ-per output sample. Nevertheless. a number of Fast QRD-RLS algorithms have been proposed with O[lYJ of complexity. Particularly thc Fast QRD-RLS al­ gorithms based on backward prediction enol'S are well known for their good numerical behaviors and low complexities. In such...

In this paper we have present performance analysis of different equalization techniques such as minimum mean– squared error (MMSE), Least mean square (LMS), Recursive Least Square (RLS) linear equalizers and MMSE-Decision Feedback equalizer (DFE), LMS-DFE, RLS-DFE non-linear equalizers in different channel conditions, in order to achieve optimal equalizer. In our simulation model we have consid...

This paper compares two adaptive methods of de-convolving the instrument responses from seismic events against the standard single-degree-of-freedom (SDOF) method. The Least Mean Squares (LMS) algorithm and the square root, Recursive Least Squares (RLS) algorithm are considered and investigated using three seismic events. Both adaptive methods do not assume any knowledge of instrument data, but...