A Modified SLM Scheme for PAPR Reduction of UFMC Systems

Abstract One of the most promising 5G waveform candidates is the universal-filtered multicarrier system (UFMC). The UFMC system reduces the out-of-band (OoB) emission, bringing about higher spectral efficiency. This is assumed to reach robustness against frequency offset and low latency. Although, as aforementioned, the UFMC system offers many advantages, it lacks high peak-to-average power ratio (PAPR) as a multicarrier transmission technique. This research paper tackles two approaches; firstly, RCS, by developing a simulated conventional SLM system, with modifications to generate the same number of waveforms, while using fewer UFMC modulators. Secondly, by developing a simulated conventional SLM system, with modifications using the same number of modulators to generate more waveforms that would be generated in the conventional scheme. The two sets of results from the proposed M-SLM scheme are compared to each other, and to other PAPR reduction schemes using OFDM and UFMC. To reduce PAPR in UFMC systems, (M-SLM) scheme with low complexity is proposed. The essence of the proposed M-SLM scheme is represented in making use of the cyclically shifting process and FMC modulator’s linearity property. The proposed M-SLM scheme uses Um UFMC modulators to produce Uw alternative UFMC waveforms, where Uw = Um (2Um − 1). As a result, drawing a comparison with existing SLM based PAPR reduction schemes for UFMC systems; the proposed M-SLM scheme's computational complexity is reduced. Finally, there is a comparison between the proposed M-SLM scheme and the schemes there in the literature according to PAPR reduction ability.

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A REVIEW OF NOVEL APPROACH FOR REDUCTION IN SUB CARRIER PEAK TO AVERAGE POWER RATIO IN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING

International Journal of Engineering Technologies and Management Research ◽

10.29121/ijetmr.v5.i2.2018.632 ◽

2020 ◽

Vol 5 (2) ◽

pp. 114-122

Author(s):

Manju Sangar ◽

Professor Brijendra Mishra ◽

Professor Bhupendra Verma

Keyword(s):

High Power ◽

Orthogonal Frequency Division Multiplexing ◽

Average Power ◽

High Mobility ◽

Low Complexity ◽

Multimedia Data ◽

Papr Reduction ◽

Frequency Division Multiplexing ◽

Power Ratio ◽

Frequency Division

In last few decades the demand for multimedia data services has grown up fastly. One of the most promising multicarrier system, Orthogonal Frequency Division Multiplexing (OFDM) allow large number of capacity the number of subcarriers, high data rates and ubiquitous coverage with high mobility. But OFDM is extensively affected by peak to average power ratio (PAPR). Unfortunately, the high PAPR inherent to OFDM signal envelopes will frequently drive high power amplifiers (HPAs) which are operate in the nonlinear region. The nonlinearity of the High Power Amplifier exhibits phase and amplitude distortions, which causes loss of orthogonality between the subcarriers; also (ICI) is introduced in the source signal. This dissertation is basically focused on PAPR reduction in OFDM system and measuring BER in different Modulation Technique. In PAPR reduction Signal companding methods have low complication, high distortion and spectral properties; however, we have limited PAPR reduction capabilities. Partial transmit sequences (PTS) and selected mapping (SLM), have also been considered for PAPR reduction. Such kind of techniques are very efficient and distortion less, Also the SLM is very good technique to the PAPR problem in single carrier system. This method has low complexity as well as it is data independent. In this paper, we are describing a combine technique of SLM and PTS to minimize the PAPR. In PTS scheme, number of sub blocks increases; the IFFT block to be performed for sub blocks also increases. Simulation results have shown that the reductions of PAPR of proposed scheme is more than PTS and SLM methods as well as the difficulty reduced considerably.

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Modified Alternative-signal Technique for Sequential Optimisation for PAPR Reduction in OFDM-OQAM Systems

Defence Science Journal ◽

10.14429/dsj.67.10642 ◽

2017 ◽

Vol 67 (3) ◽

pp. 298 ◽

Cited By ~ 2

Author(s):

M.V.R. Vittal ◽

K. Rama Naidu

Keyword(s):

Orthogonal Frequency Division Multiplexing ◽

Complexity Analysis ◽

Average Power ◽

Low Complexity ◽

Papr Reduction ◽

Power Ratio ◽

Digital To Analog Converters ◽

The Individual ◽

Very High ◽

Signal Method

<p>A modified alternative signal technique for reducing peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing systems employing offset quadrature amplitude modulation (OFDM-OQAM) is proposed. Lower PAPR reduces the complexity of digital to analog converters and results in increasing the efficiency of power amplifiers. The main objective of the algorithm is to decrease PAPR with low complexity. The alternative signal method involves the individual alternative signal (AS-I) and combined alternative signal (AS-C) algorithms. Both the algorithms decrease the peak to average power ratio of OFDM-OQAM signals and AS-C algorithm performs better in decreasing PAPR. However the complexity of AS-C algorithm is very high compared to that of AS-I. To achieve reduction in PAPR with low complexity, modified alternative signal technique with sequential optimisation (MAS-S) is proposed. The quantitative PAPR analysis and complexity analysis of the proposed algorithm are carried out. It is demonstrated that MAS-S algorithm simultaneously achieves PAPR reduction and low complexity.</p>

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An Enhanced Peak to Average Power Ratio Reduction Scheme for Interleaved and Sub-Band Orthogonal Frequency-Division Multiple Access Frameworks with Low Complexity

Journal of Computational and Theoretical Nanoscience ◽

10.1166/jctn.2019.7804 ◽

2019 ◽

Vol 16 (2) ◽

pp. 754-758

Author(s):

K. Palani ◽

D. Jagadeesan ◽

R. Jothikumar ◽

S. Susi

Keyword(s):

Orthogonal Frequency Division Multiplexing ◽

Average Power ◽

Low Complexity ◽

Power Ratio ◽

Frequency Division ◽

Major Drawback ◽

Multicarrier Transmission ◽

Time Domain Signal ◽

Power Ratio Reduction ◽

Original Time

Orthogonal Frequency Division Multiplexing (OFDM) is a multicarrier transmission technique which has the major drawback namely Peak to Average Power Ratio (PAPR). The high PAPR influences the efficiency of the power amplifier. The Selected Level Mapping (SLM) gives reduced PAPR contrasted with different strategies but the complexity is high due to the necessity of various Inverse Fast Fourier Transform (IFFTs). With the end goal to reduce the complexity, the proposed design requires only one IFFT, the candidate signals are produced by cyclic shifting the original time domain signal then multiplying with the distinctive genuine positive numbers. At that point the candidate with most minimal PAPR is chosen for transmission.

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Low Complexity Rotation Algorithm for Reducing PAPR in Partial Transmits Sequence

10.21203/rs.3.rs-264221/v1 ◽

2021 ◽

Author(s):

Thamer Alameri ◽

Nabeel ali ◽

Mothana Attiah ◽

Mohammed Saad Talib ◽

Jawad Mezaal

Keyword(s):

Computational Complexity ◽

Orthogonal Frequency Division Multiplexing ◽

Average Power ◽

Low Complexity ◽

Papr Reduction ◽

Frequency Division Multiplexing ◽

Power Ratio ◽

Frequency Division ◽

Complexity Level ◽

Novel Approach

Abstract High peak to average power ratio (PAPR) is considered as a prime challenge in orthogonal frequency division multiplexing. The partial transmits sequence (PTS) technique is one of the most effective methods for restraining the PAPR pattern. This study proposes a novel approach for enhancing PAPR reduction performance in a PTS by partitioning each subblock into two parts then exchanging the first sample with the last selection in each part of the subblock to generate a new partitioning scheme. The proposed algorithm is analysed and applied to typical traditional segmentation schemes, namely, the adjacent, interleaving and pseudo-random schemes. Moreover, simulation is conducted with two scenarios in which the number of subcarriers is set to 128 and 256. In both systems, the improved segmentation schemes demonstrate PAPR reduction performance that is superior to that of the traditional strategies. Furthermore, the computational complexity level of the enhanced adjusted PTS scheme is low compared with that of the conventional schemes.

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A Novel Hybrid Precoding-Companding Technique for Peak-to-Average Power Ratio Reduction in 5G and beyond

Sensors ◽

10.3390/s21041410 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1410

Author(s):

Mohamed Mounir ◽

Mohamed B. El_Mashade ◽

Salah Berra ◽

Gurjot Singh Gaba ◽

Mehedi Masud

Keyword(s):

Computational Complexity ◽

Orthogonal Frequency Division Multiplexing ◽

High Speed ◽

Average Power ◽

Papr Reduction ◽

Power Ratio ◽

Error Vector Magnitude ◽

Hybrid Precoding ◽

High Power Amplifier ◽

Reduction Techniques

Several high-speed wireless systems use Orthogonal Frequency Division Multiplexing (OFDM) due to its advantages. 5G has adopted OFDM and is expected to be considered beyond 5G (B5G). Meanwhile, OFDM has a high Peak-to-Average Power Ratio (PAPR) problem. Hybridization between two PAPR reduction techniques gains the two techniques’ advantages. Hybrid precoding-companding techniques are attractive as they require small computational complexity to achieve high PAPR reduction gain. Many precoding-companding techniques were introduced to increasing the PAPR reduction gain. However, reducing Bit Error Rate (BER) and out-of-band (OOB) radiation are more significant than increasing PAPR reduction gain. This paper proposes a new precoding-companding technique to better reduce the BER and OOB radiation than previous precoding-companding techniques. Results showed that the proposed technique outperforms all previous precoding-companding techniques in BER enhancement and OOB radiation reduction. The proposed technique reduces the Error Vector Magnitude (EVM) by 15 dB compared with 10 dB for the best previous technique. Additionally, the proposed technique increases high power amplifier efficiency (HPA) by 11.4%, while the best previous technique increased HPA efficiency by 9.8%. Moreover, our proposal achieves PAPR reduction gain better than the most known powerful PAPR reduction technique with a 99% reduction in required computational complexity.

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Peak-to-Average-Power-Ratio (PAPR) Reduction Methods with Wavelet Transform in MIMO-OFDM

IETE Journal of Research ◽

10.1080/03772063.2017.1355753 ◽

2017 ◽

Vol 64 (3) ◽

pp. 415-421 ◽

Cited By ~ 2

Author(s):

Murat Tören ◽

Cebrail Çiflikli

Keyword(s):

Wavelet Transform ◽

Average Power ◽

Papr Reduction ◽

Power Ratio ◽

Reduction Methods ◽

Mimo Ofdm

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Shaping Code in Conjunction with DCT for PAPR Reduction in Multicarrier System

10.21203/rs.3.rs-44862/v2 ◽

2021 ◽

Author(s):

Younes Aimer ◽

Boubakar Seddik Bouazza ◽

Smail Bachir ◽

Claude Duvanaud

Keyword(s):

Power Amplifier ◽

Power Efficiency ◽

Average Power ◽

Nonlinear Behavior ◽

Signal Amplitude ◽

Amplitude Distribution ◽

Papr Reduction ◽

Radio Link ◽

Error Vector Magnitude ◽

Multicarrier System

Abstract Nonlinear behavior and power efficiency of the Power Amplifier (PA) contradictorily depend on the input signal amplitude distribution. The transmitted signal in multi-carrier modulation exhibits high Peak-to-Average Power Ratio (PAPR) and large bandwidths, leading to the degradation of the radio link and additional generation out-of-band interferences, which degrade the quality of the transmission. Practical solutions exist, like a power back-off, but with unacceptable efficiency performances of the transmitter. This paper deals with efficiency and linearity improvement using a new PAPR reduction method based on the combination of Discrete Cosine Transform (DCT) and shaping technique. The main principle is to determine an optimal coding scheme according to a trade-off between coding complexity and performance benefits in the presence of PA non-linearities. Simulation and experimental results in the context of OFDM signal and using a 20W - 3.7GHz Radio-Frequency Power Amplifier (RF-PA) show an improvement on PAPR reduction of about 3.25dB. Also, the communication criteria like BER (Bit Error Rate) and EVM (Error Vector Magnitude) are improved by about one decade and a half and 8%, respectively.

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AN EFFICIENT METHOD FOR PAPR REDUCTION IN OFDM SYSTEMS WITH REDUCED COMPLEXITY

International Journal of Electronics and Electical Engineering ◽

10.47893/ijeee.2013.1076 ◽

2013 ◽

pp. 96-100

Author(s):

PRITANJALI KUMARI ◽

US TRIAR

Keyword(s):

Orthogonal Frequency Division Multiplexing ◽

Average Power ◽

High Peak ◽

Papr Reduction ◽

Power Calculation ◽

Frequency Division Multiplexing ◽

Power Ratio ◽

Frequency Division ◽

Ofdm Systems ◽

Reduced Complexity

Orthogonal Frequency Division Multiplexing (OFDM), widely used in digital wireless communication, has a major drawback of high Peak to Average Power Ratio (PAPR). A reduced complexity partial transmit sequence (PTS) scheme has been proposed to solve high peak to average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) system. In the proposed PTS scheme, a function is generated by summing the power of time domain samples at time ‘n’ in each sub blocks, known as “Hn”.Only those samples, having Hn greater than or equal to a preset threshold value (αT) are used for peak power calculation during the process of selecting a candidate signal with the lowest PAPR for transmission. As compared to conventional PTS scheme, the proposed scheme achieves almost the same PAPR reduction performance with much lower computational complexity.

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