This document analyzes peak-to-average power ratio (PAPR) reduction techniques for single carrier frequency division multiple access (SC-FDMA) signals used in 3GPP Long Term Evolution (LTE) networks. It proposes applying a combination of clipping and pulse shaping using a root raised cosine (RRC) filter to an SC-FDMA signal with interleaved frequency division multiple access (IFDMA) subcarrier mapping. Simulation results show this hybrid technique reduces PAPR compared to using RRC filtering alone, with greater reduction at higher RRC roll-off factors and larger block sizes. The PAPR reduction improves power efficiency for mobile devices.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
PAPR REDUCTION OF OFDM SIGNAL BY USING COMBINED HADAMARD AND MODIFIED MEU-LAW...IJCNCJournal
Orthogonal frequency division multiplexing (OFDM) is a technique which gives high quality of service (QOS) to the users by mitigating the fading signals as well as high data rates in multimedia services. However, the peak-to-average power ratio (PAPR) is a technical challenge that reduces the efficiency of RF power amplifiers. In this paper, we propose the combined Hadamard transform and modified meu-law companding transform method in order to lessen the effects of the peak-to-average power ratio of the
OFDM signal. Simulation results show that the proposed scheme reduces PAPR compared to other companding techniques as well as the Hadamard transform technique when used on its own.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
A Hybrid PAPR Reduction Scheme for OFDM System ijmnct
Orthogonal frequency division multiplexing (OFDM) i
s considered as most efficient technique for future
wireless communication systems due to its higher sp
ectral bandwidth efficiency, robustness to frequenc
y
selective fading channels, etc. However, the succes
sful implementation of the OFDM system necessitates
several difficulties. The biggest disadvantage to w
ork with OFDM system is its high peak-to-average po
wer
ratio PAPR leadsto severe inter carrier interferenc
e, out-of-band radiation, and poor bit error rate
performance due to the nonlinearity of the high pow
er amplifier. In this paper, a novel hybrid techniq
ue is
proposed to reduce PAPR further and comparison has
been done with conventional techniques as well.
Simulated results are presentedconfirm theoretical
results.MATLAB 7.5 is used to simulate the results
for system parametersconsidered.
Performance improvement for papr reduction in lte downlink system with ellipt...IJCNCJournal
This paper is concerned with the performance improvement of PAPR reduction of orthogonal frequency division multiplexing (OFDM) signal using amplitude clipping & filtering based design. Note that OFDM is one of the well adept multi-carrier multiplexing transmission scheme which has been implemented in long term evolution (LTE) downlink. Nonetheless peak to average power ratio (PAPR) is the more rattling problem with OFDM, consequently in this paper a reduction procedure of the PAPR by using amplitude clipping and filtering is proposed. Here we used IIR bandpass elliptic filter after amplitude clipping to
reduce the PAPR. The performance of the system in terms of bit error rate (BER) is also canvased as a new
filter based clipping method. Our results show that the proposed methodology of clipping method with the
IIR elliptic band pass filter significantly reduces the PAPR value.
Hybrid approach to solve the problem of papr in ofdm signal a surveyeSAT Journals
“Orthogonal frequency division multiplexing
method used to achieve the today’s need of wireless communication
3GPP Association for the use of LTE. The
higher data rate, higher bit rate, mitigated delay spread, lower multipath distortion,
OFDM system has few major issues associated with
ratio (PAPR)” associated with the signal.
interleaved OFDM, selective mapping (SLM)
windowing, clipping, filtering, tone rejection(TR), tone injection(TI), compandin
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
PAPR REDUCTION OF OFDM SIGNAL BY USING COMBINED HADAMARD AND MODIFIED MEU-LAW...IJCNCJournal
Orthogonal frequency division multiplexing (OFDM) is a technique which gives high quality of service (QOS) to the users by mitigating the fading signals as well as high data rates in multimedia services. However, the peak-to-average power ratio (PAPR) is a technical challenge that reduces the efficiency of RF power amplifiers. In this paper, we propose the combined Hadamard transform and modified meu-law companding transform method in order to lessen the effects of the peak-to-average power ratio of the
OFDM signal. Simulation results show that the proposed scheme reduces PAPR compared to other companding techniques as well as the Hadamard transform technique when used on its own.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
A Hybrid PAPR Reduction Scheme for OFDM System ijmnct
Orthogonal frequency division multiplexing (OFDM) i
s considered as most efficient technique for future
wireless communication systems due to its higher sp
ectral bandwidth efficiency, robustness to frequenc
y
selective fading channels, etc. However, the succes
sful implementation of the OFDM system necessitates
several difficulties. The biggest disadvantage to w
ork with OFDM system is its high peak-to-average po
wer
ratio PAPR leadsto severe inter carrier interferenc
e, out-of-band radiation, and poor bit error rate
performance due to the nonlinearity of the high pow
er amplifier. In this paper, a novel hybrid techniq
ue is
proposed to reduce PAPR further and comparison has
been done with conventional techniques as well.
Simulated results are presentedconfirm theoretical
results.MATLAB 7.5 is used to simulate the results
for system parametersconsidered.
Performance improvement for papr reduction in lte downlink system with ellipt...IJCNCJournal
This paper is concerned with the performance improvement of PAPR reduction of orthogonal frequency division multiplexing (OFDM) signal using amplitude clipping & filtering based design. Note that OFDM is one of the well adept multi-carrier multiplexing transmission scheme which has been implemented in long term evolution (LTE) downlink. Nonetheless peak to average power ratio (PAPR) is the more rattling problem with OFDM, consequently in this paper a reduction procedure of the PAPR by using amplitude clipping and filtering is proposed. Here we used IIR bandpass elliptic filter after amplitude clipping to
reduce the PAPR. The performance of the system in terms of bit error rate (BER) is also canvased as a new
filter based clipping method. Our results show that the proposed methodology of clipping method with the
IIR elliptic band pass filter significantly reduces the PAPR value.
Hybrid approach to solve the problem of papr in ofdm signal a surveyeSAT Journals
“Orthogonal frequency division multiplexing
method used to achieve the today’s need of wireless communication
3GPP Association for the use of LTE. The
higher data rate, higher bit rate, mitigated delay spread, lower multipath distortion,
OFDM system has few major issues associated with
ratio (PAPR)” associated with the signal.
interleaved OFDM, selective mapping (SLM)
windowing, clipping, filtering, tone rejection(TR), tone injection(TI), compandin
SLM-PTS BASED PAPR REDUCTION TECHNIQUES IN OFDM SYSTEMHariniChaganti1
Signals, which were initially sent in the analog domain, are being sent more and more in the digital domain these days. For better transmission, even single–carrier waves are being replaced by multi–carriers. Multi-carrier
systems like OFDM are now – a – days being implemented commonly. In the OFDM system,
orthogonally placed subcarriers are used to carry the data from the transmitter end to the receiver end. The presence of a guard band in this system deals with the problem of ISI and noise is minimized by a larger number of sub–carriers. But the large Peak– to –Average Power Ratio of these signal have some undesirable effects on the system. The Peak-to-Average Power Ratio is the ratio between the maximum power and average power of a complex passband signal. It causes many disadvantages like band-in and band-out variation, low signal to quantization noise ratio, low efficiency of power amplifier, etc. Hence, it is necessary to reduce PAPR in OFDM for its efficient use.
In this project, the main objective is to study the basics of an OFDM System and analyze and
simulate various methods such as clipping and filtering, selected mapping, Partial transmit sequence
to reduce the PAPR in the system and compare these techniques with and without PAPR reduction to
obtain an efficient technique so that this system can be used more commonly and effectively.
A Hybrid VLM Preceded SLM Technique Using Clipping and Filtering Method for P...IJERA Editor
MIMO-OFDM is an attractive interface for the next generation WLANs, WMAN, 4G and 5G mobile cellular
systems. However the performance of the MIMO-OFDM systems is affected by Peak to Average Power Ratio
(PAPR). PAPR is the main disadvantage associated with the MIMO-OFDM systems. So far, many techniques
have been proposed to reduce the value of PAPR but high PAPR for MIMO-OFDM systems is still a demanding
area and a different issue.In this paper, a hybrid VLM precoded SLM scheme using Clipping & Filtering has
been proposed to reduce PAPR in MIMO-OFDM systems. And it has been observed that the proposed scheme
has achieved a significant gain in PAPR reduction without increasing the system complexity and affecting the
error performance of the system.
Comparative performance analysis of different modulation techniques for papr ...IJCNCJournal
One of the most important multi-carrier tran
smission techniques used in the latest wireless com
munication
arena is known as Orthogonal Frequency Division Mul
tiplexing (OFDM). It has several characteristics
such as providing greater immunity to multipath fad
ing & impulse noise, eliminating Inter Symbol
Interference (ISI) & Inter Carrier Interference (IC
I) using a guard interval known as Cyclic Prefix (C
P). A
regular difficulty of OFDM signal is high peak to a
verage power ratio (PAPR) which is defined as the r
atio
of the peak power to the average power of OFDM Sign
al. An improved design of amplitude clipping &
filtering technique of us previously reduced signif
icant amount of PAPR with slightly increase bit err
or rate
(BER) compare to an existing method in case of Quad
rature Phase Shift Keying (QPSK) & Quadrature
Amplitude Modulation (QAM). This paper investigates
a comparative performance analysis of the differen
t
higher order modulation techniques on that design.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Low Peak to Average Power Ratio and High Spectral Efficiency Using Selective ...theijes
A low complexity peak to average power ratio (PAPR) reduction scheme for orthogonal frequency division multiplexing (OFDM) systems is proposed. All pass filters technique used PAPR is reduction but small amount of reduction, So use Selective Mapping (SLM) technique reduce PAPR and SNR increases.
Computationally Efficient Algorithm for Reducing PAPR in OFDM using Null Subc...idescitation
A new algorithm is proposed which is used with
existing null-data subcarrier switching method of Peak to
Average Power Ratio (PAPR) reduction in OFDM to lower the
computational complexity. This proposed algorithm is very
simple and achieves significant reduction in computational
overhead without sacrificing PAPR reduction capability of
null-data subcarrier switching method. The proposed
algorithm is compatible with the current commercial systems
and it can be used with other existing algorithms to reduce
the computational overhead further. The proposed algorithm
is very useful in delay sensitive services. The effectiveness of
the proposed algorithm is demonstrated by presenting
simulation results of PAPR and computational time
requirement.
AN OVERVIEW OF PEAK-TO-AVERAGE POWER RATIO REDUCTION TECHNIQUES FOR OFDM SIGNALSijmnct
OFDM (Orthogonal Frequency Division Multiplexing) has been widely adopted for high data rate wireless
communication systems due to its advantages such as extraordinary spectral efficiency, robustness to
channel fading and better QoS (Quality of Service) performance for multiple users. However, some
challenging issues are still unresolved in OFDM systems. One of the issues is the high PAPR (peak-toaverage
power ratio), which results in nonlinearity in power amplifiers, and causes out of band radiation
and in band distortion. This paper reviews some conventional PAPR reduction techniques and their
modifications to achieve better PAPR performance. Advantages and disadvantages of each technique are
discussed in detail. And comparisons between different techniques are also presented. Finally, this paper
makes a prospect forecast about the direction for further researches in the area of PAPR reduction for
OFDM signals
Comparative Analysis of PAPR Reduction Techniques in OFDM Using Precoding Tec...IJSRD
In this modern era, Orthogonal Frequency Division Multiplexing (OFDM) has been proved to be an explicit promising technique for wired and wireless systems because of its several advantages like high spectral efficiency, robustness against frequency selective fading, relatively simple receiver implementation etc. Besides having a number of advantages OFDM suffers from few disadvantages like high Peak to Average Power Ratio (PAPR), Intercarrier Interference (ICI), Intersymbol Interference (ISI) etc. These detrimental effects, if not compensated properly and timely, can result in system performance degradation. This paper mainly concentrates on reduction of PAPR.A comparisons have been made between various precoding techniques against conventional OFDM.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
An Overview : Peak to Average Power Ratio (PAPR) in OFDM system using some ne...Z AL Hashemi
An Overview : Peak to Average Power Ratio (PAPR) in OFDM system using some new PAPR techniques (with matlab code)
By
Zainab Saad Hadi AL-Hashemi
A graduate of University of Baghdad, College of Engineering Electronic & Communications Engineering Department
Impact of Clipping and Filtering on Peak to Average Power Ratio of OFDM Systemijsrd.com
Orthogonal Frequency Division Multiplexing (OFDM) is an emerging field of research in the field of 4G broadband wireless communications due to its robustness against multipath fading and relatively simple implementation. Peak to Average Power Ratio (PAPR) is the limiting factor for an OFDM system as it consists of large number of independent subcarriers as a result of which the amplitude of such a signal can have high peak values which degrades the system performance. Such a signal when amplified by a Power Amplifier without processing results spectral regrowth and intermodulation among subcarrier. Hence this non linearity destroys the orthogonally of the OFDM signal and introduces out-of-band radiation and in band distortions causing significant performance degradation. The clipping and filtering method is analysed which is an efficient and simple method to reduce the PAPR. We have shown the effects of clipping and filtering on the performance of OFDM, including the power spectral density, the crest factor, and the bit-error rate.
Analysis of Reduction of PAPR by Linear Predictive Coding in OFDM AnuragSingh1049
The major challenge in orthogonal frequency division multiplexing (OFDM) is to reduce high peak to average power ratio (PAPR) that leads to non linear distortion for the application of high power amplifier. PAPR is defined as the ratio between the maximum instantaneous power and its average power. In this paper, we have presented new PAPR reduction technique to reduce peak to average power ratio using Linear predicting coding (LPC) in OFDM system. In this paper, proposed technique show the significant reduction in PAPR without any harmful degradation in power spectral density (PSD), computational complexity (CC) and performance error of the system. This proposed method can be applied for any number of subcarrier and independent of modulation scheme under Additive White Gaussian Noise (AWGN) channel.
SLM-PTS BASED PAPR REDUCTION TECHNIQUES IN OFDM SYSTEMHariniChaganti1
Signals, which were initially sent in the analog domain, are being sent more and more in the digital domain these days. For better transmission, even single–carrier waves are being replaced by multi–carriers. Multi-carrier
systems like OFDM are now – a – days being implemented commonly. In the OFDM system,
orthogonally placed subcarriers are used to carry the data from the transmitter end to the receiver end. The presence of a guard band in this system deals with the problem of ISI and noise is minimized by a larger number of sub–carriers. But the large Peak– to –Average Power Ratio of these signal have some undesirable effects on the system. The Peak-to-Average Power Ratio is the ratio between the maximum power and average power of a complex passband signal. It causes many disadvantages like band-in and band-out variation, low signal to quantization noise ratio, low efficiency of power amplifier, etc. Hence, it is necessary to reduce PAPR in OFDM for its efficient use.
In this project, the main objective is to study the basics of an OFDM System and analyze and
simulate various methods such as clipping and filtering, selected mapping, Partial transmit sequence
to reduce the PAPR in the system and compare these techniques with and without PAPR reduction to
obtain an efficient technique so that this system can be used more commonly and effectively.
A Hybrid VLM Preceded SLM Technique Using Clipping and Filtering Method for P...IJERA Editor
MIMO-OFDM is an attractive interface for the next generation WLANs, WMAN, 4G and 5G mobile cellular
systems. However the performance of the MIMO-OFDM systems is affected by Peak to Average Power Ratio
(PAPR). PAPR is the main disadvantage associated with the MIMO-OFDM systems. So far, many techniques
have been proposed to reduce the value of PAPR but high PAPR for MIMO-OFDM systems is still a demanding
area and a different issue.In this paper, a hybrid VLM precoded SLM scheme using Clipping & Filtering has
been proposed to reduce PAPR in MIMO-OFDM systems. And it has been observed that the proposed scheme
has achieved a significant gain in PAPR reduction without increasing the system complexity and affecting the
error performance of the system.
Comparative performance analysis of different modulation techniques for papr ...IJCNCJournal
One of the most important multi-carrier tran
smission techniques used in the latest wireless com
munication
arena is known as Orthogonal Frequency Division Mul
tiplexing (OFDM). It has several characteristics
such as providing greater immunity to multipath fad
ing & impulse noise, eliminating Inter Symbol
Interference (ISI) & Inter Carrier Interference (IC
I) using a guard interval known as Cyclic Prefix (C
P). A
regular difficulty of OFDM signal is high peak to a
verage power ratio (PAPR) which is defined as the r
atio
of the peak power to the average power of OFDM Sign
al. An improved design of amplitude clipping &
filtering technique of us previously reduced signif
icant amount of PAPR with slightly increase bit err
or rate
(BER) compare to an existing method in case of Quad
rature Phase Shift Keying (QPSK) & Quadrature
Amplitude Modulation (QAM). This paper investigates
a comparative performance analysis of the differen
t
higher order modulation techniques on that design.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Low Peak to Average Power Ratio and High Spectral Efficiency Using Selective ...theijes
A low complexity peak to average power ratio (PAPR) reduction scheme for orthogonal frequency division multiplexing (OFDM) systems is proposed. All pass filters technique used PAPR is reduction but small amount of reduction, So use Selective Mapping (SLM) technique reduce PAPR and SNR increases.
Computationally Efficient Algorithm for Reducing PAPR in OFDM using Null Subc...idescitation
A new algorithm is proposed which is used with
existing null-data subcarrier switching method of Peak to
Average Power Ratio (PAPR) reduction in OFDM to lower the
computational complexity. This proposed algorithm is very
simple and achieves significant reduction in computational
overhead without sacrificing PAPR reduction capability of
null-data subcarrier switching method. The proposed
algorithm is compatible with the current commercial systems
and it can be used with other existing algorithms to reduce
the computational overhead further. The proposed algorithm
is very useful in delay sensitive services. The effectiveness of
the proposed algorithm is demonstrated by presenting
simulation results of PAPR and computational time
requirement.
AN OVERVIEW OF PEAK-TO-AVERAGE POWER RATIO REDUCTION TECHNIQUES FOR OFDM SIGNALSijmnct
OFDM (Orthogonal Frequency Division Multiplexing) has been widely adopted for high data rate wireless
communication systems due to its advantages such as extraordinary spectral efficiency, robustness to
channel fading and better QoS (Quality of Service) performance for multiple users. However, some
challenging issues are still unresolved in OFDM systems. One of the issues is the high PAPR (peak-toaverage
power ratio), which results in nonlinearity in power amplifiers, and causes out of band radiation
and in band distortion. This paper reviews some conventional PAPR reduction techniques and their
modifications to achieve better PAPR performance. Advantages and disadvantages of each technique are
discussed in detail. And comparisons between different techniques are also presented. Finally, this paper
makes a prospect forecast about the direction for further researches in the area of PAPR reduction for
OFDM signals
Comparative Analysis of PAPR Reduction Techniques in OFDM Using Precoding Tec...IJSRD
In this modern era, Orthogonal Frequency Division Multiplexing (OFDM) has been proved to be an explicit promising technique for wired and wireless systems because of its several advantages like high spectral efficiency, robustness against frequency selective fading, relatively simple receiver implementation etc. Besides having a number of advantages OFDM suffers from few disadvantages like high Peak to Average Power Ratio (PAPR), Intercarrier Interference (ICI), Intersymbol Interference (ISI) etc. These detrimental effects, if not compensated properly and timely, can result in system performance degradation. This paper mainly concentrates on reduction of PAPR.A comparisons have been made between various precoding techniques against conventional OFDM.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
An Overview : Peak to Average Power Ratio (PAPR) in OFDM system using some ne...Z AL Hashemi
An Overview : Peak to Average Power Ratio (PAPR) in OFDM system using some new PAPR techniques (with matlab code)
By
Zainab Saad Hadi AL-Hashemi
A graduate of University of Baghdad, College of Engineering Electronic & Communications Engineering Department
Impact of Clipping and Filtering on Peak to Average Power Ratio of OFDM Systemijsrd.com
Orthogonal Frequency Division Multiplexing (OFDM) is an emerging field of research in the field of 4G broadband wireless communications due to its robustness against multipath fading and relatively simple implementation. Peak to Average Power Ratio (PAPR) is the limiting factor for an OFDM system as it consists of large number of independent subcarriers as a result of which the amplitude of such a signal can have high peak values which degrades the system performance. Such a signal when amplified by a Power Amplifier without processing results spectral regrowth and intermodulation among subcarrier. Hence this non linearity destroys the orthogonally of the OFDM signal and introduces out-of-band radiation and in band distortions causing significant performance degradation. The clipping and filtering method is analysed which is an efficient and simple method to reduce the PAPR. We have shown the effects of clipping and filtering on the performance of OFDM, including the power spectral density, the crest factor, and the bit-error rate.
Analysis of Reduction of PAPR by Linear Predictive Coding in OFDM AnuragSingh1049
The major challenge in orthogonal frequency division multiplexing (OFDM) is to reduce high peak to average power ratio (PAPR) that leads to non linear distortion for the application of high power amplifier. PAPR is defined as the ratio between the maximum instantaneous power and its average power. In this paper, we have presented new PAPR reduction technique to reduce peak to average power ratio using Linear predicting coding (LPC) in OFDM system. In this paper, proposed technique show the significant reduction in PAPR without any harmful degradation in power spectral density (PSD), computational complexity (CC) and performance error of the system. This proposed method can be applied for any number of subcarrier and independent of modulation scheme under Additive White Gaussian Noise (AWGN) channel.
Enhancing PAPR reduction for FBMC-OQAM systems by joint both tone reservation...nooriasukmaningtyas
As all multi-carrier designs FBMC-OQAM signal suffers from large peak-toaverage power ratio (PAPR). There are divers PAPR reduction methods to
solve this problem. Tone reservation (TR) scheme is one of the most famous
PAPR reduction techniques in which a peak cancelling signal is added to the
original one in such a way that PAPR will reduce. Companding is another
easy PAPR reduction technique in which compression of large amplitude
samples and expansion of low one. In this paper, we suggest a new PAPR
reduction scheme called TR&Compd, based on combining tone reservation
and Mu-law companding techniques for FBMC-OQAM systems. The
simulation results show that the new proposed scheme (TR&Compd)
presents better results in term of PAPR reduction compared to TR and Mulaw companding methods taken separately.
A low complexity partial transmit sequence scheme for better papr reduction i...eSAT Journals
Abstract The main drawback of OFDM system is the high Peak to Average Power Ratio (PAPR) of the transmitted signals. Partial transmit sequence scheme is a promising algorithm to reduce the peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM). The Partial Transmit Sequence (PTS) consist of several inverse fast Fourier transform (IFFT) operations and complicated calculations to obtain optimum phase sequence which results in increasing the computational complexity of PTS. A phase sequence applied to the PTS Scheme reduces its complexity but at the expense of slight degradation in PAPR reduction. In this paper, for further reduction of PAPR the peak clipping of the OFDM signal is introduced along with the PTS with new phase sequence scheme. Since clipping is one of the simplest techniques of PAPR reduction, it does not increase the complexity of the system much and a better PAPR reduction is obtained with the combined effect of clipping and PTS with New Phase Sequence. But the clipping technique introduce some distortion in the signal, however peak clipping of signal below a particular threshold can maintain the BER in the tolerable range. The clipping threshold selected will be different for different OFDM systems. Index Terms: OFDM, Peak to Average Power Ratio (PAPR), Partial Transmit Sequence (PTS), Clipping.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Design Ofdm System And Remove Nonlinear Distortion In OFDM Signal At Transmit...Rupesh Sharma
although OFDM seems to be a solution to keep up with
the demand of increasing data rates, it has some drawbacks.
Sensitivity to high PAPR is the most significant of these
drawbacks. The main objective of this paper was to investigate
and document the effects of PAPR on the performance of OFDM
based digital communications under different channel conditions.
A step-by-step approach was adopted in order to achieve the
objective of this paper. The first step is to provide a basic
background on the principles of OFDM. The reasons for the
PAPR and a theoretical analysis of these effects on OFDM
systems are documented. The OFDM system has a high peak-toaverage
power ratio (PAPR) that can cause unwanted saturation
in the power amplifiers, leading to in-band distortion and out-ofband
radiation. To be able to observe the system behavior, the
simulation results for different channel models are presented in
graphical form. Next, the simulation results obtained in this work
are compared to the simulation results reported in related studies
Performance of Multiple symbol representation with clipping scheme for PAPR r...ijsrd.com
OFDM is one of the multicarrier modulation technique used in various communication systems. The major problem one faces while implementing this system is the high peak to average power .For an efficient OFDM system this PAPR should be low. In this paper a hybrid PAPR (peak to average power ratio) reduction technique for the OFDM (orthogonal frequency division multiplexing) signal which combines a multiple symbol representations method with a signal clipping method is proposed. In multiple symbol representations alternative signaling points are used to represent one symbol and PAPR is further reduced with the clipping scheme. The performance of the hybrid scheme is compared with the partial transmit sequence which is one of the other PAPR reduction scheme. In partial transmit sequence the input data is divided in to disjoint blocks transformed in to time domain sequence and rotated by phase factors. Theoretical analysis and simulation results validate that the proposed scheme has the ability to provide large PAPR reduction, low bit error rate. Performance analysis is also done with the partial transmit sequence scheme.
Hardware Implementation of OFDM system to reduce PAPR using Selective Level M...IOSR Journals
Abstract : OFDM is a modulation as well as multiplexing technique which is widely used in various high speed mobile and wireless communication systems because of its capacity of ensuring high level robustness against interference. In this paper the design and implementation of OFDM system along with SLM implementation to reduce PAPR[6]is illustrated and a detailed simulation of the OFDM system with 16-QAM. OFDM transceiver is implemented using FPGA Spartan6 kit. The hardware results show a detailed study of RTL schematics and Test Bench. In this paper, the software simulation results show 2dB reduction in the peaks. Keywords - Field Programmable Gate Array, Matlab Simulink, Orthogonal Frequency Division Multiplexing , Peak-to-Average Power Ratio, Selective level Mapping and Xilinx
Comparative study of selected subcarrier index modulation OFDM schemesTELKOMNIKA JOURNAL
Orthogonal frequency division multiplexing with subcarrier index modulation (SIM-OFDM) is recently proposed to enhance the performance of traditional OFDM. By incorporating the index modulation in OFDM, the data can be sent on the indices of subcarriers as well as the subcarriers themselves reducing the system complexity. In addition, the Peak to Average Power Ratio (PAPR) and Inter Carrier Interference (ICI) can be reduced by switching on /off some OFDM subcarriers in OOK fashion. In this paper, a comparative study of OFDM with SIM_OFDM and Enhanced SIM_OFDM methods in terms of complexity, spectral efficiency and bit error rate over AWGN channel using two power policies is presented. The simulation results showed that at bit error rate of 10-3, SIM_OFDM and ESIM_OFDM achieved gains in Eb/No of 1.1 dB and 2 dB over 4-QAM OFDM respectively under power reallocation policy. However, the results also showed that traditional OFDM has better spectral efficiency compared to both SIM_OFDM and ESIM_OFDM especially at high M-ary orders.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Comparative Analysis of PAPR Reduction Techniques in OFDM Using Precoding Tec...IJSRD
In this modern era, Orthogonal Frequency Division Multiplexing (OFDM) has been proved to be an explicit promising technique for wired and wireless systems because of its several advantages like high spectral efficiency, robustness against frequency selective fading, relatively simple receiver implementation etc. Besides having a number of advantages OFDM suffers from few disadvantages like high Peak to Average Power Ratio (PAPR), Intercarrier Interference (ICI), Intersymbol Interference (ISI) etc. These detrimental effects, if not compensated properly and timely, can result in system performance degradation. This paper mainly concentrates on reduction of PAPR.A comparisons have been made between various precoding techniques against conventional OFDM.
Performance Evaluation of PAPR Reduction with SER and BER by Modified Clippin...ijcsse
This paper work focuses on performance analysis of PAPR reduction of orthogonal frequency division multiplexing (OFDM) using amplitude clipping & filtering based design. Now a days one of the most proficient multi-carrier transmission techniques widely used today is orthogonal frequency division multiplexing (OFDM) which has been implemented by the next generation wireless communication technology: Long Term Evolution (LTE). Extra robustness to multipath fading and impulse noise is provided OFDM. It eliminates inter symbol interference (ISI) & inter carrier interference (ICI) with certain procedure. Therefore peak to average power ratio (PAPR) is the basic problem with OFDM. However in this paper we proposed a reduction procedure of the PAPR by using clipping and filtering. Here we use a composed high pass , low pass & Chevyshev band pass filter II after amplitude clipping to reduce the PAPR. The performance of the system in terms of bit error rate (BER) and symbol error rate (SER) is also investigated as a new filter based clipping method is proposed. Our proposed clipping method with and composed high pass the Chevyshev bandpass filter II in PAPR performance of the system with a little compromise of BER & SER showing the significant improvement in Quadrature Amplitude Modulation (QAM).
Adaptive Clipping for PAPR Reduction in OFDMIJERA Editor
A new Technique “Adaptive Clipping” is introduced to reduce the Peak to Average Power Ratio (PAPR) of OFDM system efficiently for wireless applications. In this technique, the threshold for clipping the signal is decided according to the peak size and number of peaks in the OFDM burst signal. A comparison is done between selective clipping and adaptive clipping and the results are shown in terms of Bit error rate (BER) and PAPR. Adaptive clipping offers nearly half a dB reduction in PAPR compared to selective clipping. With proposed adaptive clipping, PAPR of 3 dB is obtained with BER of 10-4 . For a particular set of signals where there are large number of peak variations, adaptive clipping is more efficient in terms of BER compared to selective clipping. The simulation of adaptive clipping is done with the MATLAB software and the BER is plotted. An IEEE 806.11 standard is used for OFDM signal Transmission.
The several assets for high-speed data transmission over wireless uses the Orthogonal Frequency Division
Multiplexing (OFDM) as it is a multicarrier transmission scheme. A large number of narrow bandwidth carriers is
therefore adopted by the OFDM. Individually for an OFDM, each subcarrier is attenuated under the frequency-selective
and fast fading channel, therefore the resulting gain is high attenuation which leads to poor performance of all OFDM
subcarriers if the same fixed transmission scheme are used. Thus the main goal of the indicated paper is to grab an
understanding of the inequality between fixed & adaptive modulations schemes as the introduction of the adaptive
modulation. The need for the above system is to make use of the speaker's voice to check their character and control
approach to administrations, for example, voice dialing data administrations, voice send, and security control for secret
data. The performance of paperwork basically states that implementation of adaptive modulation is done into blocks of
adjacent subcarriers which is the result of dividing whole subcarriers. Therefore the equivalent modulation scheme which
is the calculation of average instantaneous signal to noise (SNR) is exercised to entire subcarriers of the equal block. The
OFDM system average bit error rate (BER) performance is observed here under fixed modulation and adaptive
modulation, and these modulation techniques are recorded by accepting the different inverse fast Fourier transforms
(IFFT) size and uncomplicated adaptive Quadrature amplitude modulation (QAM) strategy. The simulation in MATLAB
shows the results as the performance of fixed modulation is inferior to that of the BER performance of OFDM system
using adaptive modulation. The prospective adaptive modulation and coding Technique uses OFDM to manage the fixed
BER under changing the channel.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
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Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
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This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
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Peak to avrage power ratio
1. International Journal of Computer Applications (0975 – 8887)
Volume 69– No.15, May 2013
26
Peak-to-Average Power Ratio Analysis of SCFDMA
Signal by Hybrid Technique
Renu Rani
Department of Electronics and
Communication Engineering
RKGIT, India
Garima Saini
Department of Electronics and
Communication Engineering
NITTTR, India
Anuj Kumar
Department of Applied
Instrumentation and Electronics
Engineering, RKGIT, India
ABSTRACT
The low peak-to-average power ratio (PAPR) in single-carrier
systems has motivated the Long Term Evolution (LTE) Third
Generation Partnership Project (3GPP) to adopt single carrier
frequency division multiple access (SC-FDMA) as the uplink
multiple access scheme. In this paper, an enhancement of a
SC-FDMA system by decreasing the PAPR is focused. A
combination of clipping and Pulse shaping (RRC filter) is
applied on a SC-FDMA signal with IFDMA subcarrier
mapping, which results in a PAPR reduction. This PAPR
reduction by hybrid (clipping & pulse shaping) technique can
be used to enhance the power efficiency of the handset, or
alternatively to improve uplink throughput and/or operating
range.
Keywords
SC-FDMA, 3GPP LTE, PAPR, RRC.
1. INTRODUCTION
The further increasing demand on high data rates in wireless
communications systems has arisen in order to support
broadband services.3GPP long term evolution (LTE) has
adopted orthogonal frequency division multiplexing access
(OFDMA) for downlink transmission and single carrier
frequency division multiple access (SCFDMA) for uplink [1].
This is to compensate for a drawback with normal OFDMA,
which has a very high peak to average power ratio
(PAPR).High PAPR requires expensive and inefficient power
amplifiers with high requirements on linearity, which
increases the cost of the terminal and drains the battery faster.
SCFDMA signal has lower PAPR because of its inherent
single carrier structure [2]. This paper is organized as follows.
In the next section, SCFDMA system model is introduced,
and then we discuss the PAPR and proposed SCFDMA
system. Performance evaluation is addressed in the following
section, and the final section concludes the paper.
2. SCFDMA SYSTEM MODEL
The basic principle of a LTE SC-FDMA transmission system
is shown in Figure.1.At the transmitter side, a baseband
modulator transmits the binary input in one of several possible
modulation formats including QPSK or 16 level-QAM.N-
point discrete Fourier transform (DFT) produce a frequency
domain representation of these modulated symbols.The output
of the DFT is then applied to consecutive inputs of a size-M
IDFT (M >N) where the unused input of IDFT are set to zero.
If they are equal (M=N), they simply cancel out and it
becomes a conventional single user single carrier system with
frequency domain equalization. However, if N is smaller than
M and the remaining inputs to the IDFT are set to zero, the
output of the IDFT will be a signal with ‘single carrier’
properties, i.e. a signal with low power variations, and with a
bandwidth that depends on N. The SC-FDMA is single
carrier, not single frequency. The data signal of each user
consists of a lot of frequency. DFT of SC-FDMA is used to
filter the frequency items and maps them into IDFT to reform
single user waveform. This may justify the reduced peak-to
average lower ratio (PAPR) experienced in the IDFT output
[3].
In SCFDMA, there are three methods of assigning the M
frequency domain modulation Symbol to subcarriers:
Distributed subcarrier mapping (DFDMA), Localized
subcarrier mapping (LFDMA), and interleaved subcarrier
mapping (IFDMA), a special case of distributed FDMA. In
the localized subcarrier mapping mode, the modulation
symbols are assigned to M adjacent subcarriers. In the
distributed mode, the symbols are equally spaced across the
entire channel bandwidth. The distributed and localized
mapping of DFT precoded data sequence to OFDM
subcarriers is sometimes collectively referred to as DFT-
spread OFDM. In general, SCFDMA signals have lower
PAPR than OFDMA signals and LFDMA incurs higher PAPR
compared to IFDMA.Though IFDMA is more desirable than
LFDMA in terms of PAPR power efficiency, LFDMA is
superior in terms of throughput. Therefore, LFDMA has been
widely implemented in LTE [2].
Clipping, companding and pulse shaping techniques are used
to improve the PAPR performance of SCFDMA signal.
Clipping is the simplest method that can limit the amplitude of
the signal to some desired threshold value. It is a nonlinear
process and may cause in-band distortion and out of-band
radiation. SC-FDMA is a single carrier modulation scheme,
and pulse shaping is required to band limit the transmitted
signal but it enlarges the PAPR of the SC-FDMA transmitted
signals. In this paper performance of IFDMA subcarrier
mapping scheme based SCFDMA system with hybrid
technique (clipping and pulse shaping filter) is analyzed in
terms of PAPR.
2. International Journal of Computer Applications (0975 – 8887)
Volume 69– No.15, May 2013
27
Figure 1. Transmitter and receiver structure of
SCFDMA system model
3. PAPR DEFINITION
The PAPR in SC-FDMA is required to be as small as
possible. The PAPR is defined as the ratio of peak power to
average power of the transmitted signal in a given
transmission block and is given by [4]:
The cumulative distribution function (CDF) of the PAPR is
one of the most performance measures for different PAPR
reduction techniques. Most researches use complementary
CDF (CCDF) instead of CDF. The CCDF of the PAPR
denotes the probability that the PAPR of a data block exceeds
a given threshold PAPR>PAPRth [5].
4. PROPOSED SCFDMA SYSTEM
After IDFT in Figure.1 the clipping and Pulse shaping
(RRCF) arrangement is implemented as shown in Figure.2.
The proposed system provides enhancement in terms of
PAPR. The clipping function is given by:
Where xn is the clipped signal, x is the base-band signal, A is
the peak amplitude and φ is the phase of the baseband signal
which has no change due to clipping [5], [6].
In a single-carrier communication system, pulse shaping is
required to band limit the signal and ensures it meets the
spectrum mask [7]. Root raised cosine (RRC) filter is used to
pulse shape the SC-FDMA signals [8].
RRC is used as the transmit and receive filter in a digital
communication system to perform matched filtering. The
combined response of two such filters is that of the raised-
cosine filter. Its name stems from the fact that the non-zero
portion of the frequency spectrum of its simplest form β = 1
(called the roll-off factor) is a cosine function. The RRC filter
is characterized by two values; β and Ts (reciprocal of the
symbol-rate). The impulse response of such a filter can be
given as:
Unlike the raised-cosine filter, the impulse response is not
zero at the intervals of ±Ts. However, the combined transmit
and receive filters form a raised-cosine filter which have zero
at the intervals of ±Ts. Only in the case of β = 0, the root
raised-cosine have zeros at ±Ts [3].
Figure 2. Block diagram of the proposed scheme
Input data
Modulation
Output data
Demodulation
N-DFT N-IDFT
Subcarrier
mapping
Subcarrier
demapping
mappingM-IDFT M-DFT
Add CP Remove CP
Channel
Pulse
shaping
Input data
Modulation
Output data
Demodulation
N-DFT
N-IDFT
Subcarrier
mapping
Subcarrier
demapping
mapping
M-IDFT
M-DFT
Clipping
Remove CP
Channel
Add CP
3. International Journal of Computer Applications (0975 – 8887)
Volume 69– No.15, May 2013
28
The method of applying algorithm is summarized as follow:
1. The binary input signal is passed through the modulation,
introducing blocks of data symbols.
2. Each block of data symbols is converted to frequency
domain by DFT operation.
3. After DFT spread, Subcarrier mapping and IDFT operation
is applied to the block of symbols.
4. After that, the amplitude of the signal in the time domain is
clipped and RRC filtering is applied. Then PAPR is
computed.
5. SIMULATION RESULTS
Computer simulations are performed using MATLAB to
validate the results. To evaluate the PAPR of system
configuration we simulated the transmission of 105
random
data points. After calculating the PAPR the data was presented
as an empirical complementary cumulative distribution
function (CCDF).Table.1 illustrates the parameters
implemented in the simulation for the SC-FDMA system
using interleaved allocation.
Table 1. Simulation Parameters
Description Parameter
System bandwidth 5 MHz
No. of subcarriers 512
Data block size 16, 64, 128
Roll off factor 0.1, 0.3, 0.5
Oversampling factor 4
No. of iteration 105
Modulation data type QAM
Subcarrier mapping IFDMA
Figures.3 and 4 show the simulation results. The CCDF of the
PAPR for proposed SCFDMA system with IFDMA subcarrier
mapping scheme is shown in Figure 3.Modulation scheme
is16QAM, M=512, N=16.Root raised cosine filter with roll
off factor 0.1, 0.3 and 0.5 is used after clipping. With clipping
technique reduction in PAPR is obtained by adjusting clipping
level.
It can be seen that PAPR for proposed SCFDMA is reduced
with increasing the roll off factor for RRC filter from 0.1 to
0.5. This is because as β increases (i.e. larger excess
bandwidth), the RRC filter ripples decay faster. Thus, the peak
value of the transmit signal waveform will reduce
appropriately. RRC filter with high roll off factor reduces
PAPR significantly but price paid is increased bandwidth
requirement. So a middle value of roll off factor is chosen
according to application.
From simulation results it is also clear that if IFDMA with
clipping and RRC pulse shaping is applied on a different
number of subcarriers better PAPR reductions performances
can be achieved for a large number of subcarriers. In Figure.4
increasing N from 16 to 128 with roll off factor 0.5, the PAPR
of proposed SCFDMA system is reduced up to 4.9dB. It is
clear that there is a decrease in the PAPR for the proposed
scheme compared to the conventional.
1 2 3 4 5 6 7 8 9
10
-5
10
-4
10
-3
10
-2
10
-1
10
0
PAPR[dB]
CCDF
rrc(beta=0.1)
rrc(beta=0.3)
rrc(beta=0.5)
Proposed(beta=0.1)
Proposed(beta=0.3)
Proposed(beta=0.5)
Figure 3. Comparison of PAPR for proposed
and rrc pulse shaping with different
roll off factor
1 2 3 4 5 6 7
10
-5
10
-4
10
-3
10
-2
10
-1
10
0
PAPR [dB]
CCDF
N=16
N=64
N=128
Figure 4. CCDF of PAPR for Proposed
SCFDMA with different N
6. CONCLUSION
In this paper, an efficient SC-FDMA system with clipping and
pulse shaping is presented and studied. Simulation results
show that the proposed technique with IFDMA subcarrier
mapping and 16QAM modulation performs better in terms of
PAPR .The results show that proposed IFDMA system can
maintain a low PAPR for a very large number of subcarriers.
It is concluded that there is a decrease in the PAPR up to
4.9dB for the proposed scheme compared to the conventional
by controlling number of symbols, roll off factor, clipping
level. The resulting PAPR reduction can be used to enhance
handset power efficiency.
4. International Journal of Computer Applications (0975 – 8887)
Volume 69– No.15, May 2013
29
7. REFERENCES
[1] Meza C.A, Kyujin Lee, Kyesan Lee, 2011, “PAPR
reduction in single carrier FDMA uplink system using
parametric linear pulses”, ICT Convergence (ICTC),
International Conference, pp.424-429.
[2] Enchang Sun, Ruizhe Yang, Pengbo Si, Yanhua Sun, and
Yanhua Zhang, 2010, “ Raised Cosine-like companding
scheme for peak-to-average power ratio reduction of
SCFDMA signals”,IEEE conference,pp.978-983.
[3] Rana M. M., Jinsang Kim and Won-Kyung Cho,2010,
“PAPR Reduction Technique for LTE SC-FDMA
Systems Using Root-Raised Cosine Filter”,(IJCSIS)
International Journal of computer Science and
Information Security, Vol. 8, No. 6, pp.66-71.
[4] Myung G.H.,Lim J.and Goodman D.J., 2006,“Peak-to-
Average power Ratio of Single Carrier FDMA Signals
with Pulse Shaping”, in Proceeding of the IEEE
International Symposium on Personal, Indoor and Mobile
Radio Communications, pp.1-5.
[5] Al-Kamali F.S., Dessouky M.I.,Sallam B.M., El-Samie
F.E., 2011, “Peak-to-Average Power Ratio Reduction for
SCFDMA using Distortion Reduction Algorithm”,
International Journal of Research and Reviews in
Computer Science (IJRRCS) ,Vol. 2, No. 3, pp.793-799.
[6] Rana. M.M., 2008, “Clipping Based PAPR Reduction
Method for LTE OFDMA Systems”, International
Journal of Electrical & Computer Sciences IJECS-
IJENS, Vol. 10, No.05, pp. 45-48.
[7] Mansor Z., Nix A., and McGeehan Joe,2010, “PAPR
Reduction for Single Carrier FDMA LTE Systems using
Frequency Domain Spectral Shaping”, International
Journal of Research and Reviews in Computer Science
(IJRRCS), Vol. 2, No. 3,pp.371-376.
[8] Radi W., Hesham ElBadawy, Salwa ElRamly,2011,“
Peak to Average Power Ratio Reduction Techniques for
Long Term Evolution- Single Carrier Frequency Division
Multiple Access System”, (IJAEST) , Vol. 6,No. 2,
pp.230 – 236.