The main drawback of OFDM is its high peak to average power ratio (PAPR). High PAPR of OFDM makes it unusable in non-linear systems. So the clipping signals scheme is one useful and simple method to reduce the PAR. In the widely used OFDM (Orthogonal Frequency Division Multiplexing) systems, the FFT and IFFT pair are used to modulate and demodulate the data constellation on the subcarriers. Thi...

The MIMO technology towards achieving future generation broadband networks design criteria is presented. Typical next generation scenarios are investigated. The MIMO technology is integrated with the OFDM technology for effective space, time and frequency diversity exploitations for high speed outdoor environment. Two different OFDM design kernels (fast Fourier transform (FFT) and wavelet packe...

Other than the conventional fast Fourier transform (FFT) for multicarrier modulation, a new approach for multicarrier modulation (MCM) has been known. Meanwhile, multicarrier modulation involves dividing the broadband channel into many orthogonal but overlapping narrowband carriers. In an OFDM modulation based multicarrier system using the FFT, a cyclic prefix (CP) is inserted after each symbol...

A high data rate multi-carrier receiver employing orthogonal frequency division multiplexing (OFDM) for mobile communications requires joint low-power VLSI design optimization of the channel equalizer and demodulator. Although the multi-carrier receiver structure can be greatly simplified by use of the Fast Fourier Transform (FFT) for demodulation, the physical hardware complexity of the FFT is...

In this paper, we present a frequency-domain receiver for ZP-OFDM schemes (Zero-Padded Orthogonal Frequency Division Multiplexing) where the duration of the channel impulse response is a significant fraction of the duration of the OFDM block. The proposed receiver has a relatively low complexity, allowing an FFT-based (Fast Fourier Transform) implementation. The proposed receiver is suitable to...

The best approach for real time application to achieve high throughput and network capacity for fourth generation wireless local area networks is to combine MIMO wireless technology with OFDM. This paper focuses on high level Matlab Simulink 4 x 4 spatially multiplexed (SM) MIMO OFDM transceiver encoded at 1⁄2 rate using 64 size FFT which is designed and implemented on Spartan Virtex 6 FPGA boa...

To reduce the peak OFDM signals that can be distorted by the nonlinearity of power amplifiers, this project has proposed an efficient structure for implementing the tone reservation method that assigns appropriate data to reserved tones. In the proposed structure, a new binary search algorithm is proposed for the peak OFDM signal Clipping, and the FFT is replaced with an approximate DFT in whic...

The latest Research Trend in wireless communication is implementing wireless system on SDR (Software Define Radio), so the SDR implementation of MIMO-OFDM receiver with channel state information is presented in this paper. Here we use Xilinx 13.1 Spartan 3 xc3s400pq208 FPGA device. The simulation results are obtained for 2x2 MIMO-OFDM receiver system in which we have implemented channel estimat...

In the present scenario, there is a rising demand of high capacity, high performance and low Bit Error Rate (BER) in Wireless Communication systems. The Orthogonal Frequency Division Multiplexing (OFDM) is an attractive multi carrier modulation technique for wireless transmission systems. In this paper, we discuss the effect of Doppler frequency in Fast Fourier Transform (FFT) based OFDM system...