Multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) is a promising candidate for 4G broadband wireless communications. However, one main disadvantage of MIMO-OFDM is that the signals transmitted on different antennas might have large peak-to-average power ratio (PAPR). A new concurrent PAPR reduction algorithm based on the property of orthogonal space-time bloc...

Orthogonal frequency division multiplexing (OFDM) is a strong candidate for future wireless communication because it is marked by its higher frequency multiplicity and greater immunity to multipath fading. However, the main drawback of OFDM is high peak-to-average power ratio (PAPR), which leads to power inefficiency and requires expensive high power amplifier (HPA) with very good linearity. In...

Abstract A possible problem of orthogonal frequency division multiplexing (OFDM) is its high peak-to-average power ratio (PAPR). Recently, the single carrier (SC) transmission system with frequency-domain equalization is attracting much attention. In this paper, a novel approach to alleviate the PAPR problem of OFDM is proposed. A generalized OFDM (GOFDM) with frequency-domain equalization is p...

OFDM systems have the inherent problem of a high peak to average power ratio (PAPR). OFDM Suffers as the no of Subcarriers operating in the large dynamic range operates in the non-linear region of amplifier due to OFDM suffer the PAPR problem Application of high power amplifiers results in increased component cost. In general, there has been a trade-off between PAPR reduction and computational ...

Orthogonal frequency division multiplexing (OFDM) is an attractive, promising and emerging technique which achieves high data rate in mobile multipath channels. LTE was the first technology to use OFDM. There are many more advantages of OFDM which includes immunity to multipath fading. High Peak to Average Power Ratio(PAPR) is the main disadvantage of OFDM-LTE Networks. This paper describes how...

This paper proposes two low complexity methods in time domain for limiting Peak to Average Power Ratio (PAPR) in Orthogonal Frequency Division Multiplexing (OFDM) systems by employing cyclically shifted sequences with different delay and phase factors. Since the proposed method operates in time domain it requires only two Fast Fourier Transform (FFT) operations to achieve significant PAPR reduc...

We consider the channel estimation for two-way relay OFDM networks. We proposed an LS-based channel estimation algorithm under block-based training schemes. Based on the mean square error (MSE) criterion, the condition and the design method for optimal training sequences are discussed. To reduce peak-to-average power ratio (PAPR), a special sequence called Zadoff-Chu sequence is employed to des...

Orthogonal Frequency Division Multiplexing (OFDM) has been used in many advanced wireless communication systems due to its high spectral efficiency and robustness to frequency selective fading channels. However, the major concern with OFDM system is the high peak-to-average power ratio (PAPR) of the transmitted signal. Some of the popular techniques used for PAPR reduction in OFDM system are co...

Orthogonal frequency division multiplexing (OFDM) is a method of encoding digital data over a multiple carrier frequencies. OFDM stands for Orthogonal Frequency Division Multiplexing and also it is a modulation technique for transmitting large amounts of digital data over a radio wave. OFDM for wireless communications is used for PAPR reduction techniques. KeywordsOFDM, Peak-Average-Power Ratio...

This proposed method reduces the peak-to-average power ratio (PAPR) of multi-carrier transmission, by exploiting null subcarriers, already mandated in most OFDM wireless standards. This new approach requires no channel side information, can be compatible with existing standards, imposes no rate hit, is distortionless, has low computational complexity, and can complement most other PAPR-reductio...