scholarly journals PAPR Performance Analysis of low Complexity SLM for Various Phase Sequences in MIMO-OFDM System

2019 ◽  
Vol 8 (2) ◽  
pp. 4347-4353
Keyword(s):  
Communication Systems ◽  
Orthogonal Frequency Division Multiplexing ◽  
Average Power ◽  
Multipath Fading ◽  
Low Complexity ◽  
Superior Performance ◽  
Ofdm Systems ◽  
Phase Sequence ◽  
Mimo Ofdm ◽  
Papr Performance

Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing (MIMO OFDM) is a key technology for contemporary communication systems due to its spectral efficiency, higher data rates, better diversity gain, good link reliability and both inter symbol interference (ISI) and multipath fading free transmission. However, due to the presence of OFDM, MIMO-OFDM suffers from high peak to average power ratio (PAPR). Even though, several schemes are available to mitigate PAPR, there is no standard solution. Selective Mapping (SLM) significantly reduces the PAPR in OFDM systems at the cost of computational complexity (CC). The CC of SLM can be reduced by proper design of SLM. This paper considers a low complexity SLM (LC SLM) scheme in which both the CC and length of the index of selected phase sequence are significantly reduced. The PAPR of an SLM-OFDM depends on the number of subcarriers in OFDM, the number of candidate blocks in SLM and selected phase sequence and this paper investigate various phase sequences and analyses their PAPR performance. Simulation results show the superior performance of Riemann sequence over the other phase sequences.

Factors Influencing the PAPR Performance of OFDM and MIMO-OFDM Systems

2019 ◽  
Vol 11 (3) ◽  
pp. 23-33 ◽  
Author(s):  
Tahreer Mahmood ◽  
Seshadri Mohan
Keyword(s):  
Orthogonal Frequency Division Multiplexing ◽  
Multiple Input Multiple Output ◽  
Average Power ◽  
Channel Fading ◽  
Ofdm Systems ◽  
Practical Applications ◽  
Factors Influencing ◽  
Mimo Ofdm ◽  
Modulation Schemes ◽  
Papr Performance

Multiple-input multiple-output technology together with orthogonal frequency division multiplexing (MIMO-OFDM) is an effective technique to combat multi-channel fading and to improve bandwidth efficiency. Simultaneously, it also increases the system's ability to provide reliable transmission. However, the main disadvantage of OFDM is the high peak-to-average-power ratio (PAPR), which, if not mitigated, will negatively impact practical applications. The high PAPR increases complexity and Bit Error Rate. In this research, the authors investigate the factors influencing the PAPR performance of both OFDM and MIMO-OFDM systems. The objective of this research is to make researchers in this field become familiar with this problem as well as to impart an understanding of the factors that influence PAPR. In this study, the authors classify the factors that impact PAPR into modulation schemes and a number of sub-carriers. These parameters influence the PAPR performance have been analyzed and simulated by using MATLAB. It is observed that the numbers of sub-carriers have a great effect on the PAPR performance. However, modulation schemes can have a small effect on PAPR performance.

scholarly journals An Efficient Two-Stage Receiver Base on AOR Iterative Algorithm and Chebyshev Acceleration for Uplink Multiuser Massive-MIMO OFDM Systems

Electronics ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 92
Author(s):  
Yung-Ping Tu ◽  
Chih-Yung Chen ◽  
Kuang-Hao Lin
Keyword(s):  
Iterative Algorithm ◽  
Communication Systems ◽  
Orthogonal Frequency Division Multiplexing ◽  
Multiple Input Multiple Output ◽  
Superior Performance ◽  
Ofdm Systems ◽  
Two Stage ◽  
Multiuser Detector ◽  
Input Multiple Output ◽  
Mimo Ofdm

The massive multiple-input multiple-output systems (M-MIMO) and orthogonal frequency-division multiplexing (OFDM) are considered to be some of the most promising key techniques in the emerging 5G and advanced wireless communication systems nowadays. Not only are the benefits of applying M-MIMO and OFDM for broadband communication well known, but using them for the application of the Internet of Things (IoT) requires a large amount of wireless transmission, which is a developing topic. However, its high complexity becomes a problem when there are numerous antennas. In this paper, we provide an effective two-stage multiuser detector (MUD) with the assistance of the accelerated over-relaxation (AOR) iterative algorithm and Chebyshev acceleration for the uplink of M-MIMO OFDM systems to achieve a better balance between bit error rate (BER) performance and computational complexity. The first stage of the receiver consists of an accelerated over-relaxation (AOR)-based estimator and is intended to yield a rough initial estimate of the relaxation factor ω, the acceleration parameter γ, and transmitted symbols. In the second stage, the Chebyshev acceleration method is used for detection, and a more precise signal is produced through efficient iterative estimation. Additionally, we call this proposed scheme Chebyshev-accelerated over-relaxation (CAOR) detection. Conducted simulations show that the developed receiver, with a modest computational load, can provide superior performance compared with previous works, especially in the MU M-MIMO uplink environments.

scholarly journals PAPR Reduction Using Fireworks Search Optimization Algorithm in MIMO-OFDM Systems

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Lahcen Amhaimar ◽  
Saida Ahyoud ◽  
Ali Elyaakoubi ◽  
Abdelmoumen Kaabal ◽  
Kamal Attari ◽  
...  
Keyword(s):  
Computational Complexity ◽  
Communication Systems ◽  
Orthogonal Frequency Division Multiplexing ◽  
Multiple Input Multiple Output ◽  
Average Power ◽  
Papr Reduction ◽  
Main Concern ◽  
Ofdm Systems ◽  
Fireworks Algorithm ◽  
Mimo Ofdm

The transceiver combination technology, of orthogonal frequency division multiplexing (OFDM) with multiple-input multiple-output (MIMO), provides a viable alternative to enhance the quality of service and simultaneously to achieve high spectral efficiency and data rate for wireless mobile communication systems. However, the high peak-to-average power ratio (PAPR) is the main concern that should be taken into consideration in the MIMO-OFDM system. Partial transmit sequences (PTSs) is a promising scheme and straightforward method, able to achieve an effective PAPR reduction performance, but it requires an exhaustive search to find the optimum phase factors, which causes high computational complexity increased with the number of subblocks. In this paper, a reduced computational complexity PTS scheme is proposed, based on a novel swarm intelligence algorithm, called fireworks algorithm (FWA). Simulation results confirmed the adequacy and the effectiveness of the proposed method which can effectively reduce the computation complexity while keeping good PAPR reduction. Moreover, it turns out from the results that the proposed PTS scheme-based FWA clearly outperforms the hottest and most important evolutionary algorithm in the literature like simulated annealing (SA), particle swarm optimization (PSO), and genetic algorithm (GA).

scholarly journals Pilot-Aided Frame Synchronization in Optical OFDM Systems

2020 ◽  
Vol 10 (11) ◽  
pp. 4034 ◽  
Author(s):  
Funmilayo B. Offiong ◽  
Sinan Sinanović ◽  
Wasiu O. Popoola
Keyword(s):  
Communication Systems ◽  
Orthogonal Frequency Division Multiplexing ◽  
Average Power ◽  
Visible Light Communication ◽  
Low Complexity ◽  
Frame Synchronization ◽  
Ofdm Systems ◽  
Pilot Symbol ◽  
Pilot Signal ◽  
Symmetric Property

Efficient frame synchronization is essential for data recovery in communication systems. In this study, a single pilot sequence is used to achieve both frame synchronization and peak-to-average power ratio (PAPR) reduction. The two systems considered are direct-current biased optical orthogonal frequency division multiplexing (DCO-OFDM) and asymmetrically clipped O-OFDM (ACO-OFDM). The pilot symbol is allocated to odd indexed subcarriers only. Thus, the synchronization algorithm leverages the mirror symmetric property of the pilot symbol within a frame to detect the start of the pilot signal at the receiver. This scheme has low complexity and gives precise frame synchronization at signal-to-noise ratios as low as 4 dB in an indoor visible light communication (VLC) channel.

scholarly journals Low-Complexity Distortionless Techniques for Peak Power Reduction in OFDM Communication Systems

2012 ◽  
Vol 2012 ◽  
pp. 1-13
Author(s):  
A. Ghassemi ◽  
T. A. Gulliver
Keyword(s):  
Computational Complexity ◽  
Communication Systems ◽  
Orthogonal Frequency Division Multiplexing ◽  
Average Power ◽  
Low Complexity ◽  
Inverse Discrete Fourier Transform ◽  
Peak Power Reduction ◽  
And Performance ◽  
Selective Mapping ◽  
Papr Performance

A high peak-to-average power ratio (PAPR) is one of the major drawbacks to using orthogonal frequency division multiplexing (OFDM) modulation. The three most effective distortionless techniques for PAPR reduction are partial transmit sequence (PTS), selective mapping (SLM), and tone reservation (TR). However, the high computational complexity due to the inverse discrete Fourier transform (IDFT) is a problem with these approaches. Implementation of these techniques typically employ direct computation of the IDFT, which is not the most efficient solution. In this paper, we consider the development and performance analysis of these distortionless techniques in conjunction with low-complexity IFFT algorithms to reduce the PAPR of the OFDM signal. Recently, proposed IFFT-based techniques are shown to substantially reduce the computational complexity and improve PAPR performance.

scholarly journals Experimental Evaluation of Machine learning based MIMO-OFDM System for Optimal PAPR and BER

2021 ◽  
Vol 16 ◽  
pp. 315-327
Author(s):  
Y. K Shobha ◽  
H. G Rangaraju
Keyword(s):  
Machine Learning ◽  
Error Rate ◽  
Communication Systems ◽  
Orthogonal Frequency Division Multiplexing ◽  
Multiple Input Multiple Output ◽  
Average Power ◽  
Low Complexity ◽  
Spatial Multiplexing ◽  
Operational Cost ◽  
Mimo Ofdm

The hypothetically convenient structure is the Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) technique that is employed for upcoming generations in wireless communication systems. Some of the benefits offered by MIMO-OFDM are enhanced spatial multiplexing, reliability and network throughput, and so on. Due to the integration of spatial antenna that is based on multi-stream, the problems which are related to significantly high power takes place in the system of OFDM and provides complex processing strategies. Some of the popularly known systems that are used for standardizing the Peak to average power ratio (PAPR) are partial transmit sequences (PTS), adoptive tone reservation (ATR), probabilistic mapping, and clipping which are required to be truncated and aims for minimizing the operational cost. The framework of hybrid Selective Mapping (SLM)-PTS proposed in this paper minimizes the operational cost by integrating strategies of PTS and SLM. A reduction approach that is suitable for PAPR and BER are chosen for optimization purposes depending on the statistical threshold constraint of PAPR and Bit Error Rate (BER). Thus, the system preferred with the help of the machine learning technique demonstrates the efficiency in implementing a generalized strategy to evaluate a low complexity MIMO-OFDM model. Ultimately, with the help of the PAPR and BER techniques-driven from value bound the performance of the error rate is evaluated in this framework that interactively changes from one technique.

scholarly journals Palm Date Leaf Clipping: A New Method to Reduce PAPR in OFDM Systems

Information ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 190 ◽  
Author(s):  
Brahim Bakkas ◽  
Reda Benkhouya ◽  
Idriss Chana ◽  
Hussain Ben-Azza
Keyword(s):  
Communication Systems ◽  
Orthogonal Frequency Division Multiplexing ◽  
High Speed ◽  
Average Power ◽  
Papr Reduction ◽  
Frequency Division ◽  
Ofdm Systems ◽  
Leaf Clipping ◽  
Hyperbolic Cosine ◽  
Transmitted Signal

Orthogonal frequency division multiplexing (OFDM) is the key technology used in high-speed communication systems. One of the major drawbacks of OFDM systems is the high peak-to-average power ratio (PAPR) of the transmitted signal. The transmitted signal with a high PAPR requires a very large linear range of the Power Amplifier (PA) on the transmitter side. In this paper, we propose and study a new clipping method named Palm Clipping (Palm date leaf) based on hyperbolic cosine. To evaluate and analyze its performance in terms of the PAPR and Bit Error Rate (BER), we performed some computer simulations by varying the Clipping Ratio (CR) and modulation schemes. The obtained results show that it is possible to achieve a gain of between 7 and 9 dB in terms of PAPR reduction depending on the type of modulation. In addition, comparison with several techniques in terms of PAPR and BER shows that our method is a strong alternative that can be adopted as a PAPR reduction technique for OFDM-based communication systems.

scholarly journals Investigation on the PAPR performance of odd-bit QAM constellations for DFT spread OFDM systems

2021 ◽  
Vol 21 (2) ◽  
pp. 1005
Author(s):  
Ahmed M. Sana ◽  
Amer T. Saeed ◽  
Yaseen Kh. Yaseen
Keyword(s):  
Communication Systems ◽  
Adaptive Modulation ◽  
Average Power ◽  
Transmission Efficiency ◽  
Distribution Functions ◽  
Cumulative Distribution ◽  
Ofdm Systems ◽  
Single Carrier ◽  
Papr Performance

<p>Adaptive quadrature amplitude modulation (QAM) is a crucial scheme that enables the modern communication systems to overcome the adverse effects of channel fluctuations and maintain an acceptable spectral efficiency. In order to enhance adaptive modulation even further, adoption of odd-bit QAM constellations alongside even constellations had been suggested to improve the transmission efficiency of adaptive QAM modulation. Hence, odd-bit QAM had been extensively studied, analyzed, and tested by many researchers for various patterns, sizes, and communication systems in terms of bit error rate (BER) and peak to average power ratio (PAPR). However, the PAPR performance of odd-bit QAM constellation with single carrier transmission systems adopted in the uplink of the 4G long term evolution (LTE) standards caught almost no research interest. In this paper, the PAPR performance of both cross and rectangular odd-bit QAM constellations are investigated for DFT-S-OFDM systems. Complementary cumulative distribution functions (CCDFs) and probability density functions (PDFs) curves for PAPR are also obtained. Finally, an equation for PAPR PDF is empirically derived for odd-bit cross QAM based DFT-S-OFDM. The results show that cross odd-bit QAM outperforms the rectangular odd-bit QAM in terms of PAPR by 1.02 dB for 8-QAM and 1.3 dB for 32-QAM. This proves that cross odd-bit QAM is a better choice in terms of PAPR for DFT-S-OFDM systems. </p>

scholarly journals A low complexity partial transmit sequence approach based on hybrid segmentation scheme

2020 ◽  
Vol 9 (6) ◽  
pp. 2371-2379
Author(s):  
Ali Hussein Fadel ◽  
Hasanain H. Razzaq ◽  
Salama A. Mostafa
Keyword(s):  
Orthogonal Frequency Division Multiplexing ◽  
Average Power ◽  
Low Complexity ◽  
Frequency Division ◽  
Ofdm Systems ◽  
Wave Shape ◽  
Data Sequence ◽  
Practical Applications ◽  
Phase Rotation ◽  
Hybrid Segmentation

The partial transmit sequences (PTS) is regarded as a promising scheme for inhibiting ‎the high peak-to-average power ratio (PAPR) problem in the orthogonal frequency division ‎multiplexing (OFDM) systems. The PTS scheme relies on partitioning the ‎data sequence into subsets and weighting these subsets by a group of the phase rotation ‎factors. Although the PTS can efficiently reduce the high PAPR value, a great ‎computational complexity (CC) level restricts the utilization of the PTS scheme in practical ‎applications. In PTS, there are three common types of segmentation schemes; ‎interleaving (IL-PTS), pseudo-random (PR-PTS), and adjacent (Ad-PTS) schemes. This ‎paper presents a new algorithm named hybrid pseudo-random and interleaving cosine wave shape ‎‎(H-PRC-PTS) by combining the PR-PTS scheme and the symmetrical ‎interleaving cosine wave shape (S-IL-C-PTS) scheme which was proposed in our previous ‎work. The results indicate that the suggested algorithms can ‎diminish the PAPR value like the PR-PTS scheme, whereas the CC level is reduced significantly.

Sign in / Sign up

Export Citation Format

Share Document