In this paper, the problem of frame synchronization in orthogonal frequency division multiplexing (OFDM) system is considered. For an OFDM system, frame synchronization is achieved by forcing the receiver to start its FFT at the right time. One way in which this may be achieved is to precede the OFDM data with a special synchronization symbol. Two synchronization symbols are proposed to achieve...

In broadband wireless communication, the adaptive antenna array (AAA) is combined with orthogonal frequency division multiplexing (OFDM) to combat the inter-symbol interference (ISI) and the directional interferences. One of the two main techniques which are used in OFDM systems is called Pre-FFT, where an optimum beamformer weight set is obtained in time domain before Fast Fourier Transform (P...

Carrier Interferometry (CI) approaches, including Carrier-Interferometry Orthogonal Frequency Division Multiplexing (CI/OFDM) and Pseudo-Orthogonal Carrier-Interferometry OFDM (PO-CI/OFDM), have been proposed to enhance OFDM’s performance and reduce OFDM’s peak-to-average power ratio (PAPR). However, the existing high-throughput, high-performance PO-CI/OFDM system is limited for real signaling....

Recent studies suggest that multicarrier systems using wavelets outperform conventional OFDM systems using the FFT, in that they have well-contained side lobes, improved spectral efficiency and BER performance, and they do not require a cyclic prefix. Here we study the wavelet packet and discrete wavelet transforms, comparing the BER performance of wavelet transform-based multicarrier systems a...

To increase data rate of wireless medium with higher performance, OFDM (orthogonal frequency division multiplexing) is used. Here DWT (Discrete wavelet transforms) is adopted in place of FFT (Fast Fourier transform) for frequency translation. Modulation schemes such as 16-QAM (Quadrature amplitude modulation) have been used in the development of OFDM system using DWT. In this paper, I propose a...

For a low-power wireless communication, a fast-Fourier-transform (FFT) LSI for an orthogonal frequency division multiplexing (OFDM) system has been implemented with current-mode circuits. In this current-mode OFDM system, a voltage-current converter (VIC) should be designed with an operating frequency of more than 40 MHz, because the frequency bandwidth of the OFDM signal is recommended as 20 M...

Spectrum has valuable resource in wireless communication. In wireless communication some spectrum is waste due to uses of cyclic prefix (cp) in FFT multicarrier sampling. In place of FFT used DFT and wavelet transform function for removal of cyclic prefix. Wavelet based OFDM, particularly using DWT and WPT-OFDM as situations for Fourierbased OFDM with the focus on impulse noise effects. We begi...

MIMO communication is mainly use in the OFDM to improve the communication performance and capacity. DWT based MIMO-OFDM is used in this paper. Compare to the FFT based MIMO-OFDM it has lot advantages. There is no need for cyclic prefix, flexibility and optimal resolution. Ripple(Wavelet) concept has developed as a fresh scientific implement with the aim of preserve be functional in several appl...