Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system is a new wireless broadband technology which has gained great popularity for its capability of high rate transmission and its robustness against multi-path fading and other channel impairments. Irrespective of the techniques being employed in wireless communication System (such as OFDM, MIMO, or MIMO-OF...

This paper presents a design of DFT-spread OFDM system applied to an underwater acoustic channel. It does not only combine all the advantages of a conventional OFDM system but also reduces the peak-to-average power ratio of the transmit signal. Besides, the scheme spreads the information over several subcarriers as a result of the application of an additional DFT operation and leads to a divers...

High-data rate techniques in communication systems have gained considerable attraction in recent years. Strong candidates for these communication systems are Multiple Input Multiple Output (MIMO) systems, Orthogonal Frequency Division Multiplexing (OFDM) system and MIMO-OFDM systems. MIMO systems have shown their potential by improving the diversity gain with scheme as Space-Time Block Codes (S...

In current common channel estimation schemes for MIMO OFDM systems, channel state information is usually achieved by estimating channels according to frequency domain pilot sequences. However, when the length of MIMO OFDM symbols is larger than that of wireless channel delay, there are two intractable issues in the case of cellular fast fading channel scenarios with large numbers of users, i.e....

In this paper, we propose a joint carrier frequency synchronization and channel estimation algorithm for multipleinput and multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems. A major challenge to MIMO-OFDM systems is how to obtain the channel state information accurately and promptly for coherent detection of information symbols and channel synchronization. MIMOOFDM ...

In this paper we are studying the power line channel noise in the frequency domain. The noise is measured using a spectrum analyzer. The channel noise profile is essential when OFDM is applied. Moreover, noise measurements are statistically processed in order to extract the probability density functions of the noise power for more than 120 different frequencies in the frequency range 1.15MHz-30...

Orthogonal Frequency Division Multiplexing (OFDM) is considered an effective technique in high speed digital transmission because of its spectral efficiency, robustness in different multipath propagation, and capability to fight with inter-symbol interference (ISI). On the other hand, as the speed of the mobile terminal increases, the channel becomes time-selective and variations of the channel...

The Carrier Frequency Offset (CFO) due to timevarying fading channel is the main cause of the loss of orthogonality among OFDM subcarriers which is linked to inter-carrier interference (ICI). Hence, it is necessary to precisely estimate and compensate the CFO. Especially for mobile broadband communications, CFO and channel gain also have to be estimated and tracked to maintain the system perfor...

--In this paper Bit Error Rate performance of BPSK modulation and OFDM -BPSK System over Rayleigh fading channel is analyzed. The performance of BER of BPSK over AWGN and Rayleigh channel is compared. OFDM is a orthogonal frequency division multiplexing to reduce intersymbol interference problem. Simulation of BPSK signals is carried with both AWGN and Rayleigh channel. Finally simulations of O...

OFDM is a promising technique being used for bandwidth efficient communication over the power-line channel. It provides excellent possibilities to adapt to the frequency-selectivity of the channel. The influence of impulsive noise on the OFDM transmission is not well analyzed yet. We choose Middletons Class A man-made noise model to statistically describe the impulsive interference and study th...