Orthogonal frequency-division multiplexing (OFDM) is a well-known technique for transmission of high rate data over broadband frequency-selective channels that mitigates intersymbol interference (ISI) caused by the delay spread of wireless channels. Space Frequency Block Coded technique (SFBC) is a spatial diversity technique used to achieve full transmission diversity with higher capacity. The...

This paper proposes the assignment of resource blocks (RBs) to reduce the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) in a multi-user OFDM system. This system ranks the users according to the channel state information (CSI) for RB assignment. In our proposed technique, an RB is assigned to either the firstor second-ranked mobile station (MS) to minimi...

This paper contains the Hadamard Transform in the SLM for the reduction of high peak to average power ratio (PAPR) in MIMOOFDM systems. In this technique, the input sequence is multiplied by a set of phase rotation vectors respectively and then applies the Hadamard Transform to the each resulting sequence based on SFBC. After that perform the Inverse Fast Fourier Transform in order to get the t...

orthogonal frequency division multiplexing (OFDM) is the most popular modulation technique in modern wireless communication systems. Even though there are many advantages of OFDM, it has two main drawbacks: High peak-to-average power ratio (PAPR) and frequency offset. In this paper the issue of PAPR in OFDM is discussed. Due to the large number of subcarriers used, OFDM systems have a large dyn...

The transmit signals in an OFDM system can have high peak values in the time domain since many subcarrier components are added via an IFFT operation. Therefore, OFDM systems are known to have a high PAPR (Peak-to-Average Power Ratio), compared with single-carrier systems. In fact, the high PAPR is one of the most detrimental aspects in the OFDM system, as it decreases the SQNR (Signal-to-Quanti...

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 its high amplitude fluctuations measured by Peak-to-average Power ratio (PAPR), which leads to power inefficiency and requires expensive High power ampli...

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 paper analyzes the Peak-to-Average Power Ratio (PAPR) problem in Multicode-Code Division Multiple Access (MC-CDMA) systems. The statistical distribution of PAPR is derived and the achievable PAPR reduction for a given code rate is estimated. We show that the PAPR in MC-CDMA communications systems can be reduced by Partial Transmit Sequence (PTS) and Selected Mapping (SLM) approaches. In PT...

Clipping and filtering can be a simple and effective method of reducing the peak-to-average power ratio (PAPR) for an orthogonal frequency division multiplexed (OFDM) signal. To be effective the clipping must be performed on an oversampled version of the time domain signal, but this results in out-ofband (OOB) power. It has previously been shown that the OOB signals can be filtered out using a ...