This paper presents a new algorithm for the channel estimation of the OFDM system based on a pilot signal for the new generation of high data rate communication systems. In orthogonal frequency division multiplexing (OFDM) systems over fast-varying fading channels, channel estimation and tracking is generally carried out by transmitting known pilot symbols in given positions of the frequency-ti...

This paper investigates the performance of MultipleInput Multiple-Output (MIMO) feedback system combined with Orthogonal Frequency Division Multiplexing (OFDM). Two types of codebook based channel feedback techniques are used in this work. The first feedback technique uses a combination of both the long-term and short-term channel state information (CSI) at the transmitter, whereas the second t...

MMSE-FDE can improve the transmission performance of OFDM combined with time division multiplexing (OFDM/TDM), but knowledge of the channel state information and the noise variance is required to compute the MMSE weight. In this paper, a performance evaluation of OFDM/TDM using MMSE-FDE with pilot-assisted channel estimation over a fast fading channel is presented. To improve the tracking abili...

In this paper, review 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. A multipleinput multiple-output (MIMO) communication system combined with the orthogonal frequency...

In this paper, we exhibit 2×2 MIMO framework utilizing alamouti space time Block code for level blurring channel. In non level blurring channel i.e. recurrence particular multipath channel, convolution of the channel drive reaction with STBC yield crushes the orthogonality of the STBC that can be comprehended by utilizing Orthogonal Frequency division Multiplexing (OFDM). At long last, we contr...

Ultra wideband (UWB) communication is mainly used for short range of communication in wireless personal area networks. Orthogonal Frequency Division Multiplexing (OFDM) is being used as a key physical layer technology for Fourth Generation (4G) wireless communication. OFDM based communication gives high spectral efficiency and mitigates Inter-symbol Interference (ISI) in a wireless medium. In t...

Abstract— Diagonal Bell Laboratories Layered Space-Time (DBLAST) structure offers a low complexity solution to realize the attractive capacity of Multiple-input and multiple-output (MIMO) systems. In this paper, we apply D-BLAST in orthogonal frequency division multiplexing (OFDM) systems and address the issue of channel estimation. Different from other MIMO-OFDM, where symbols at all tones are...

Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing (MIMO-OFDM) systems play a vital role in the channel estimation. The wireless channel suffers from impairments like fading and interference. Technologies that achieved above requirements are Multiple Input Multiple Output (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM). Channel impairments must be mitigated a...

The widespread application of OFDM for local area mobile wireless broadband systems is strongly motivated by the simple equalization it a ords. OFDM's bottleneck of channel-dependent performance was only recently addressed by replacing the cyclic pre x (CP) with trailing zeros (TZ). Such zero-padded OFDM transmissions enable FIR channel-irrespective symbol recovery which results in signi cant B...

Throughput is an important performance measure for data communications over a wireless channel. Orthogonal frequency division multiplexing (OFDM) with hybrid automatic repeat request (HARQ) achieves a good throughput performance over a frequency-selective fading channel. In OFDM with HARQ, however, during the first transmission uncoded information packet is transmitted. Consequently, the channe...