Orthogonal Frequency Division Multiplexing (OFDM) is a digital multicarrier transmission technique which is based on Frequency division Multiplexing. Several multimedia standards uses Time Frequency Training Orthogonal Frequency Division Multiplexing (TFT-OFDM) as the key modulation technique. This paper introduces a high accurate, low complexity compressive sensing (CS) based channel estimatio...

In this paper, challenges regarding the provision of channel state information (CSI) and carrier frequency synchronization for multiple input multiple output orthogonal frequency division multiplexing (MIMO-OFDM) systems with null subcarriers are addressed. We propose a novel maximum likelihood (ML) based scheme that estimates the aggregate effects of the channel and carrier frequency offset (C...

This paper analyzes performance and throughput of an adaptive bit allocation and variable rate algorithm depending on channel state information (CSI) and a transmit power in a multi-user OFDM transmission. The purpose of the presented multi-rate OFDM system using adaptive modulation is to increase bandwidth efficiency by controlling constellation size and to adapt proper service for each user a...

This paper investigates the problem of joint phase tracking and channel decoding in OFDM based Physical-layer Network Coding (PNC) systems. OFDM signaling can obviate the need for tight time synchronization among multiple simultaneous transmissions in the uplink of PNC systems. However, OFDM PNC systems are susceptible to phase drifts caused by residual carrier frequency offsets (CFOs). In the ...

We present a methodology for OFDM link capacity and bit error rate calculation that jointly captures the aggregate effects of various real life receiver imperfections such as: carrier frequency offset, channel estimation error, outdated channel state information due to time selective channel properties and flat receiver I/Q imbalance. Since such an analytical analysis is still missing in litera...

Due to its good orthogonality, slantlet transform (SLT) is used in orthogonal frequency division multiplexing (OFDM) systems to reduce intersymbol interference (ISI) and intercarrier interference (ICI). This eliminates the need for cyclic prefix (CP) and increases the spectral efficiency of the design. Finite Radon transform (FRAT) mapper has the ability to increase orthogonality of subcarriers...

Orthogonal frequency division multiplexing (OFDM), which uses a number of narrowband orthogonal sub-carriers, is a promising transmission technique. Also multi-carrier code division multi-access (MC-CDMA), which combines OFDM and frequency-domain spreading, has been attracting much attention as a future broadband wireless access. It was shown that MC-CDMA has lower channel capacity than OFDM, d...

An experimental analysis to evaluate the practical suitability of the Underwater Acoustic (UWA) communication scheme is the major aim of this study. Oceanic channel imposes two major challenges (i.e., multipath propagation and Doppler effects) for underwater acoustic communication. Being fastest possible underwater information exchanger, OFDM is considered as the most viable option for mitigati...

Multiband Orthogonal Frequency Division Multiplexing (MB-OFDM) approach using UWB signals with short duration of pulses provide unique advantages in short-range high data rate wireless applications which include easy penetration through obstacles, high precision ranging and low processing power. In this paper a performance study on MB-OFDM is attempted for high data rate ultra wideband (UWB) WP...

A multiple-input multiple-output (MIMO) communication system combined with the orthogonal frequency division multiplexing (OFDM) modulation technique can achieve reliable high data rate transmission over a broadband wireless channel. A main challenge in wireless communication is retrieval of the channel state information and ICI cancellation. The channel estimation and ICI cancellation is estim...