Orthogonal Frequency Division Multiplexing (OFDM) is a well-known technique for the broadband wireless communication system. However, a main problem in OFDM is its vulnerability to frequency offset errors due to which the orthogonality is destroyed that result in Inter carrier Interference (ICI). ICI causes power leakage among subcarriers thus degrading the system performance. This paper studie...

A novel least-squares (LS) scheme to estimate the channel frequency response (CFR) for orthogonal frequency division multiplexing (OFDM) over slow fading channels is presented. We take the advantage of slow fading to use repeated OFDM training blocks. This not only can facilitate the LS formulation but also improve the channel estimation performance as compared to the conventional one block LS ...

Orthogonal frequency division multiplexing (OFDM) has developed into a popular scheme for wideband digital communications used in consumer applications such as digital broadcasting, wireless networking and broadband internet access. In the OFDM system, carrier frequency offset (CFO) causes intercarrier interference (ICI) which significantly degrades the system error performance. In this paper w...

In orthogonal frequency-division multiplexing (OFDM)based wireless local area networks (WLANs), phase noise (PHN) and residual frequency offset (RFO) can cause the common phase error (CPE) and the inter-carrier interferences (ICI), which seriously degrade the performance of systems. In this letter, we propose a combined pilot symbol assisted and decision-directed channel estimation scheme based...

In this letter, we introduce frequency-domain spacetime transmit diversity (STTD) encoding/decoding to orthogonal frequency division multiplexing combined with time division multiplexing (OFDM/TDM) on a frame-by-frame basis (i.e., over several concatenated OFDM signals in the frequency-domain) to achieve both spatial and frequency diversity gains and improve the bit error rate (BER) performance...

In this paper, the potential of orthogonal frequencydivision multiplexing-code-division multiplexing (OFDM-CDM) combined with the pre-equalization is investigated. The codedivision multiplexing (CDM) component within an orthogonal frequency-division multiplexing (OFDM) system enables additional diversity in frequencyand time-selective mobile radio channels. While, by applying pre-equalization a...

Orthogonal Frequency Division Multiplexing(OFDM) is a method in which modulation of signal is done. Orthogonal Frequency Division Multiplexing has become popular technique for transporting large amount of data in both wired and wireless communication. It is a digital modulation technique in which signal is transmitted in parallel mode. As compared to single carrier system OFDM is more unaffecte...

Orthogonal frequency division multiplexing has drawn explosive attention as a new type of high data rate transmission scheme for wireless communication system. The main advantage of OFDM system are spectral bandwidth efficiency and robustness against frequency selective fading or narrowband interference etc. However a critical drawback of OFDM is high peak-to-average-power ratio (PAPR), which r...

Wavelet packet-division multiplexing (WPDM) is a high-capacity, flexible, and robust multiple-signal transmission technique in which the message signals are waveform coded onto wavelet packet basis functions for transmission. In this letter, we derive an expression for the probability of error for a WPDM scheme in the presence of both impulsive and Gaussian noise sources and demonstrate that WP...