Orthogonal Frequency Division Multiplex (OFDM) is recently widely used in many wireless and wire line communication systems. The parallelism between RS code and OFDM modulation with consecutive suppressed carriers is known. In this paper the capability of OFDM modulation to act as an error correcting code is analyzed if used for transmission over channel with impulsive noise. New decoding algor...

In the presented paper, the principle of frequency domain channel estimation for wireless OFDM systems will be shown. A well known noise reduction technique will be adapted to HIPERLAN/2 and IEEE802.11a standards, and its positive effects will be demonstrated by simulation results. Channel tracking has not been considered by the WLAN standards named above, although it is well known that time-va...

Signal-Perturbation-Free Semi-Blind Channel Estimation forMIMO-OFDM Systems Feng Wan, Ph.D.Concordia University, 2009 Multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) has been considered as a strong candidate for the beyond 3G (B3G) wirelesscommunication systems, due to its high data-rate wireless transmission performance.It is well known...

The increasing demand on real time application to achieve high throughput, reliable wireless system and network capacity for fourth generation wireless local area networks is to combine MIMO wireless technology with OFDM. Orthogonal Frequency Division Multiplexing (OFDM), which offers reliable high bit rate wireless system with reasonable low complexity. OFDM does provide large data rates with ...

In this letter, we propose a simple adaptive switching scheme to enhance the performance of space-time/frequency block coded OFDM systems (STBC/SFBC-OFDM). Since STBC-OFDM and SFBCOFDM undergo severe performance degradation in timeand frequencyselective fading channels, respectively, performance enhancement can be achieved by switching between STBC-OFDM and SFBC-OFDM over a continuously varying...

In this paper we present two throughput enhancing detection schemes for OFDM, all using the Frequency Domain Channel Length Indicator (FCLI) algorithm for improved channel estimation and joint mobile channel impulse response length estimation. At first we introduce a novel optimized detection scheme for guardinterval-free OFDM reception. In contrast to traditional OFDM, omitting the guard inter...

Super-orthogonal block codes in space-time domain (i.e., Super-orthogonal space-time trellis codes (SOSTTCs)) were initially designed for frequency nonselective (FNS) channels but in frequency selective (FS) channels these super-orthogonal block codes suffer performance degradation due to signal interference. To combat the effects of signal interference caused by the frequency selectivity of th...

In this paper, we analyze the Bit Error Rate (BER) performance of Golden coded Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system over Rician multipath fading channel. We also compare the performance of the MIMO-OFDM system using Golden code in Rayleigh and Rician multipath fading channels. We discuss the effects of the presence of line-of-sight (LoS) c...

This paper deals with the simulation of Nakagami fading in wireless channels using Orthogonal Frequency Division Multiplexing (OFDM) technique using Differential Quadrature Phase Shift Keying (DQPSK) modulation scheme. The paper proposes approximate methods for deriving Bit Error Rate (BER) in DQPSK-OFDM systems over frequency-selective Nakagami fading channels. The numerical results are plotte...

The use of frequency-domain interleaving on a frame-byframe basis for orthogonal frequency division multiplexing (OFDM) combined with time division multiplexing (OFDM/TDM) is presented. In conventional OFDM, FDE is not designed to exploit the channel frequencyselectivity and consequently, the frequency diversity gain cannot be obtained. To further improve the bit error rate (BER) performance of...