A new multiuser detection scheme is proposed which employs the adaptive minimum mean square error (MMSE) detection in combination with the successive interference cancellation. Through the theoretical analysis and the numerical examples, it is shown that the proposed detector provides a superior performance to the existing ones in terms of the asymptotic multiuser efficiency (AME) and the bit e...

Three different adaptive diagonalizers are compared on a probability of symbol error performance basis for dual-channel M-QAM systems. One diagonalizer (0 3) greatly outperforms the other two, and any comparison of the performance of the diagonalizers to that of the minimum mean square error (MMSE) canceller should be based on 0 3. Receiver structures are also presented.

Abstract In this paper hybrid ARQ is applied to DS-CDMA with minimum mean square error frequency-domain equalization (MMSE-FDE). The throughput of turbo-coded HARQ is evaluated in addition to the packet error rate (PER). DS-CDMA with MMSE-FDE can provide much better PER performance than with rake combining in a frequency-selective fading channel and the performance improves with the increase in...

In a frequency-selective fading channel, the performance of non-spread-spectrum singlecarrier (SC) transmission degrades significantly due to severe intersymbol interference (ISI). The joint use of space–time transmit diversity (STTD), receive antenna diversity and frequency-domain minimum mean square error (MMSE) equalisation in non-spread SC transmission is studied. Space–time encoding and de...

In this paper, an equalization algorithm based on soft–decision feedback, designed for transmission with square QAM constellations is introduced. The algorithm employs a minimum mean–squared error (MMSE) filter in each iteration in order to refine the data estimates. The rule for generating soft decisions is adapted continuously to the current state of the algorithm. It is shown that the algori...

Frequency-domain equalization (FDE) based on minimum mean square error (MMSE) criterion is a promising equalization technique for the broadband single-carrier (SC) transmission. However, the presence of timing offset produces the inter-symbol interference (ISI) and degrades the bit error rate (BER) performance. In this paper, we discuss the mechanism of the BER performance degradation in the pr...

This paper presents an empirical mode decomposition (EMD) based adaptive filter (AF) for channel estimation in OFDM system.  In this method, length of channel impulse response (CIR) is first approximated using Akaike information criterion (AIC). Then, CIR is estimated using adaptive filter with EMD decomposed IMF of the received OFDM symbol. The correlation and kurtosis measures are used to sel...

An expression of the minimum mean square error (MMSE) of the linear MMSE channel estimation is given in the case of a non-invertible channel covariance matrix, as in single-input single-output (SISO) OFDM system. A matrix expression, already proposed for a multiinput multi-output OFDM system in a previous article, is not valid in SISO. A new proof is then proposed, by deriving a scalar expressi...

In this paper, a residual echo cancellation method is proposed that uses an estimation of the minimum mean-square error (MMSE) based on a statistical model of a speech signal and an echo signal. After the suppression of the echo signal based on the adaptive filter, residual echo is further reduced by the proposed MMSE estimator and the results are compared with the conventional Wiener filter ba...

The minimum mean square error (MMSE) estimation problem for a discrete-index reciprocal Gaussian process impaired by additive white Gaussian noise is completely solved in the general case of noisily observed Dirichlet random boundary conditions. Finite sets of recursive equations are obtained for the computation of the filtered sequence and of the fixed-point, fixed-interval, and fixed-lag smoo...