In mobile communication systems with multisensor antennas at base stations, downlink channel estimation plays a key role because accurate channel estimates are needed for transmit beamforming. One efficient approach to this problem is channel probing with feedback. In this method, the base station array transmits probing (training) signals. The channel is then estimated from feedback reports pr...

In this paper, we discuss iterative channel estimation for the Long Term Evolution (LTE) downlink. The LTE standard utilizes coherent detection and therefore to achieve a high data rate over mobile radio channels, it is essential to obtain high accurate channel state information at the receiver side. For channel estimation purposes, the LTE standard provides training data known as pilot symbols...

As conventional methods deal with channel estimation and synchronization separately, they can’t achieve the best performances because the unknown parameters will interfere with each other. Besides, the convergence speed is slow using expectation maximization algorithm. Thus in this paper, we propose a joint synchronization and channel estimation method in MIMO-OFDM systems. The algorithm achiev...

MIMO-OFDM (multiple input multiple output-orthogonal frequency division multiplexing) is an excellent technique used in modern wireless communication systems. It has excellent quality of high speed data/voice transmission with high spectral efficiency. The Least Square (LS) and Minimum Mean Square Error (MMSE) channel estimation are the most common methods presented by several researchers. Disc...

In this paper, we study the performance of the bootstrap channel estimation scheme, which consists in this paper in using the hard-decided outputs of the channel decoder in order to extend the training sequence. Based on a simple large system analysis, we derive the expression of the channel estimation MSE in order to evaluate the impact of using wrong decisions on channel estimation performanc...

Recent progress in wireless receiver design has been towards iterative processing, where channel estimation and decoding is considered a joint optimization problem. Sparse channel estimation is another recent advancement, which exploits the inherent structure of those wireless channels that are composed of a small number of multipath components. In this work we design iterative receivers which ...

in this paper, for the purpose of investigating horizontal sound propagation, based on the results obtained from practical measurements in the strait of hormoz and available data on sound speed variations at different depths, a comprehensive model for shallow water multipath underwater acoustic channel is presented. mathematical modeling of multipath effect is based on ray theory and the image ...

In this paper, the channel estimation techniques for multiband (MB) OFDM ultra-wideband (UWB) wireless communications are investigated. By combining orthogonal frequency-division multiplexing (OFDM) with multi-band, the MB-OFDM systems can capture multipath energy more efficiently than single-band directsequence UWB (DS-UWB). However, most researches for UWB channel estimation are focused on th...

For wireless transmission, the channel estimation is necessary to improve the performance of receiver. In the ultra-wideband (UWB) wireless systems, there are two practicable modulation schemes: orthogonal frequency-division multiplexing (OFDM) and single-carrier direct-sequence UWB (DS-UWB). The OFDM based scheme is an attractive mode because it can capture the multipath energy more efficientl...

This paper derives the channel estimation of a discrete cosine transform-(DCT-) based orthogonal frequency-division multiplexing (OFDM) system over a frequency-selective multipath fading channel. Channel estimation has been proved to improve system throughput and performance by allowing for coherent demodulation. Pilot-aided methods are traditionally used to learn the channel response. Least sq...