For high data rate communication with the required Quality of Service (QoS) in 3G and 4G systems, Orthogonal Frequency Division Multiplexing (OFDM) is proposed. We present a novel discrete Fourier transform (DFT)-based channel estimator for orthogonal frequency-division multiplexing (OFDM) systems. The conventional DFT-based estimator zeroes out noise-dominant values in the transform domain, wh...

In this paper to improve the channel estimation accuracy in OFDM system , channel state information is required for signal detection at receiver and its accuracy affects the overall performance of system and it is essential to improve the channel estimation for more reliable communications. This paper addresses channel estimation based on time-domain channel statistics, using a general model LS...

Widely linear (WL) minimum mean square error (MMSE) channel estimation scheme have been proposed for multiband orthogonal frequency division multiplexing ultra-wideband (MB-OFDM UWB) systems dealing with non-circular signals. This WLMMSE channel estimation scheme provides significant performance gain, but it presents a high computational complexity compared with the linear one. In this paper, w...

We propose a new wavelet domain image interpolation scheme based on statistical signal estimation. A linear composite MMSE estimator is constructed to synthesize the detailed wavelet coefficients as well as to minimize the mean squared error for high-resolution signal recovery. Based on a discrete time edge model, we use low-resolution information to characterize local intensity changes and per...

A single-channel source separation (SCSS) algorithm is targeted to estimate the underlying unknown signals from their single-channel recorded mixture. Current SCSS methods often neglect the phase information in their parameter estimation and use the noisy phase in the signal reconstruction stage. In this paper, we investigate the impact of phase information in the parameter estimation stage of ...

Orthogonal frequency-division multiplexing (OFDM) is one of the promising techniques for future mobile wireless data systems. For OFDM systems with cochannel interference, adaptive antenna arrays can be used for interference suppression. This paper focuses on a key issue for adaptive antenna arrays, that is, parameter estimation for the minimum mean square error (MMSE) diversity combiner (DC). ...

In this paper, we introduce a generalized minimum meansquare error short-time spectral amplitude estimator with a new prior estimation of the speech probability density function based on momentcumulant transformation. From the objective and subjective evaluation experiments, we show the improved noise reduction performance of the proposed method. key words: generalized MMSE STSA estimator, spee...

The problem of estimating propagation delays of orthogonally modulated signals in asynchronous DSCDMA system over time-varing Rayleigh-fading channels is treated in this paper. The Maximum Likelihood (ML) estimator and its unaffordable complexity for implementation are discussed. Some suboptimal solutions, e.g., whitened sliding correlator, MMSE estimator, subspace-based estimator, approximate ...

In this paper, we propose the low-rank pilot-symbolaided (PSA) channel estimator for multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems. The group-wise pilot patterns are also proposed for the low-rank channel estimator. We evaluate the performance of the proposed low-rank channel estimator for various mobile channel environments by computer simulation...