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Partial transmit sequence (PTS) is one of the effective techniques for reducing the peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) systems. PTS technique has some issues such as higher computational complexity due to its exhaustive searching of optimal phase factors. In order to overcome this drawback, a sca...
Citations
... To address this limitation, the method was augmented by using a scaled-down version of the particle swarm optimization algorithm. This enhancement facilitates a more rapid and computationally efficient discovery of optimal phase factors that contribute to lower PAPR [21]. In the traditional particle swarm optimization (PSO) algorithm, the introduction of a scaling factor into the velocity update equation enhances the inertia, weight, and velocity of the particle, leading to accelerated convergence towards the optimal solution and an efficient reduction in the PAPR. ...
The orthogonal time–frequency space (OTFS) waveform is a modulation scheme for wireless communication that achieves high spectral efficiency by exploiting multipath propagation, offering robustness to Doppler shifts and delay spread. A high peak-to-average power ratio (PAPR) is considered to be a significant issue in the OTFS waveform, drastically reducing the performance of the framework. PAPR affects system performance by causing power amplifiers to operate inefficiently at high power levels, leading to increased power consumption, distortion, and reduced spectral efficiency. In this study, we combined the partial transmission sequence (PTS) and selective mapping (SLM) with the bacterial foraging algorithm (BFA), which is also known as the SLM-BFA and PTS-BFA. An extensive search for the optimal phase factors in the PTS and SLM can be computationally expensive. BFO mimics the foraging behavior of bacteria to efficiently navigate the search space. BFO intelligently finds the optimal phase factors, reducing the computation and PAPR values of the OTFS. The performance of the proposed hybrid schemes was simulated for Rayleigh and Rician channels for 64 and 256 subcarriers, respectively. Parameters such as PAPR, bit error rate (BER), and power spectral density (PSD) were analyzed and compared with those of conventional SLM and PTS methods. The projected hybrid methods obtained a significant PAPR gain of 7.9 and 11.9 dB for 64 subcarriers and 7.5 dB and 8.9 dB for 256 subcarriers with Rayleigh and Rician channels, respectively. Further, it is seen that the proposed methods effectively retained the BER performance of the framework with trivial intricacy. In conclusion, using PTS and SLM techniques, which have been improved by the BFA, makes OTFS waveform communication systems work better. These methods effectively mitigate the PAPR issue and improve the system efficiency and spectral utilization. The synergy between the PTS, SLM, and BFA offers a promising approach for overcoming the challenges in OTFS modulation, contributing to the advancement of robust and efficient wireless communication technologies.
... The optimal selection of phase factors was achieved by the application of several optimization approaches, including PSO, Simulated Annealing (SA), Genetic Algorithms (GA). These strategies were employed to overcome the restrictions associated with the use of PTS [13]. In the PTS technique, the input data block is divided into many distinct sub-blocks, each of which is independent. ...
Orthogonal frequency division multiplexing (OFDM) is a widely used multicarrier modulation (MCM) technique in the field of wireless communications, specifically designed to facilitate high-speed data transmission. The use of several subcarriers inside an OFDM system for the transmission of modulated symbols results in the generation of OFDM signals with a significant peak-to-average power ratio (PAPR). In this study, we propose a novel approach for mitigating the high PAPR in wireless communication systems (WCS). Our method utilizes a partial transmit sequence (PTS) strategy, which is enhanced by using an adaptive particle swarm optimization (PSO) algorithm. In this study, we present a description of an OFDM system employing the standard PTS technique in conjunction with PSO. To mitigate computational complexity, the suggested methodology efficiently explores the optimal amalgamation of phase rotation components. Experimental findings demonstrate that the computational complexity and PAPR have been greatly minimized by the suggested method.
... Several approaches have been taking into consideration to reduce PAPR [8], including clipping and refining [9], tone injection (TI) [10], active constellation expansion (ACE) [11], tone reservation (TR) [12], and manifold signal depiction schemes such as selected mapping (SLM) [13], and nonlinear companding transforms [14], along with partial transmit sequence (PTS) [15]. Of the current schemes, PTS is considered unique most likely to improve the PAPR of an OFDM signal because of its Longitudinal Method and zero sign deformation [16,17]. This is important as PTS categories of two methods that characterized as partitioning the original OFDM into a set of disjoint subblocks; the other one is to render a group of aspirant signs via adding phase rotated subblocks to select the minimum PAPR for broadcast [18]. ...
This paper proposes an enhanced PAPR reduction technique which combines an enhanced PTS method with Mu-Law companding. The enhanced PTS method improves performances in both the partitioning and phase rotation steps. Enhancement in partitioning is achieved through a judicious incorporation of AP-PTS scheme into the IP-PTS. As for phase rotation, an optimal set of rotation vectors is derived based on the correlation properties of candidate signals. The PAPR reduction of this enhanced PTS method is further improved by annexing Mu-Law companding at the end of the enhanced PTS. This application of Mu-Law characteristic in the time domain of OFDM signal significantly improves the PAPR reduction capability of the approach. Simulation results show that the PAPR performance of the enhanced PTS method with Mu-Law companding technique on various scenarios with different modulation schemes is better than that of the PRP-PTS. This approach can be considered as a very attractive candidate for achieving a significant reduction of PAPR, while maintaining a low computational complexity.
... P. Sanjana et al. [18] proposed a scaled PSO algorithm to mitigate the PAPR in OFDM systems with a minimum computational complexity as a comparison to the PTS technique, which uses an exhaustive searching of optimum parameters. A scaled factor has been introduced in the velocity of the particle to get faster convergence to the optimum value, and reducing PAPR as well. ...
Orthogonal Frequency Division Multiplexing (OFDM) is the best choice for wireless and wired high data rate communications. The OFDM system has many advantages such as high spectral efficiency, robustness to channel fading, and immunity to impulse interference. However, it has a main drawback, which is the Peak to Average Power Ratio (PAPR). Selecting Mapping (SLM) and Partial Transmit Sequences (PTS) are the two essential techniques for reducing the PAPR; however, they need to send side information to indicate how the transmitter generates signals. In this paper, Particle Swarm Optimization (PSO)-based dummy sub-carriers are inserted with the data to reduce PAPR without transmitting side information. The incorporation of PSO-based Dummy Sub-carriers Insertion (DSI) method on this system is performed by measuring the PAPR at the IFFT output (Inverse Fast Fourier Transform) after adding 6 adaptive sub-carrier sequences to the input data of IFFT. The PSO-based dummy algorithm decides to send the data once the PAPR of this data sequence and dummy sub-carrier is under a specific threshold. Using MATLAB as a mathematical simulation tool, simulation results are presented for a standard OFDM network model. The network model has been simulated in an Additive White Gaussian Noise (AWGN) channel environment to investigate PAPR and Bit-Error Rate (BER) performance. The simulation results show that the dummy sequence based on PSO reduces PAPR down to 4 dB compared to a conventional OFDM system and down to 3 dB compared with the clipping technique for the same BER performance.
... This way, the PTS technique does not evaluate all of the phase factor's combination to find the best one, thus, simplifying the technique. Eqs. 2 and 3 show the formula to calculate the velocity and the position of the particle [7]. ...
... Where x denotes the position of the particle, t denotes the time, v denotes the velocity, c1 and c2 denotes the local and global coefficient, r denotes the random variable with uniform distribution in the range of between 0 to 1 [8]. denotes the inertia weight of the particle and is a dimensionless variable that is scaling the inertia weight [7]. The x with a superscript of p is denoting a local best and the x with a superscript of g denotes a global best. ...
The usage of FFT that has become the key concept in OFDM system produces a high PAPR value. In order reduce it, there are several techniques that can be implemented, such as the Palm Date Leaf clipping, and the Partial Transmit Sequence. Previous researchers have evaluated each technique individually. This paper is proposing to evaluate the PAPR value as the effect of combining the Partial Transmit Sequence (PTS) with the Palm Date Leaf (PDL) clipping technique. The evaluation is done with several modulation technique, such as QPSK, 8-PSK, 16-PSK, 8-QAM, and 16 QAM. Since low PAPR performance is not advantageous if the signal's BER value is worsen, thus the evaluation also considers the BER performance of the signal. In this case, the Author focuses on the BER performance over AWGN channel. The result shows that in all of the scenarios, PTS technique could improve the signal's BER and PAPR performance for a low CR value such as 5 dB and 7 dB. Additionally, for the higher CR value such as 10 dB and 20 dB, the signal's BER performance is similar with the normal OFDM signal. Even so, it provides a consistent PAPR reduction of approximately 3 dB. Do note that the PAPR is evaluated as per CCDF of. This way, PTS technique always provide improvement in BER performance of the signal. As for the PAPR performance, PTS technique is able to improve all cases except for 8-QAM and 16-QAM signal with clipping technique at low clipping ratio such as 5 dB. However, PTS technique still requires Side Information (SI), and it has high computational complexity.
... The principle of PTS is to reduce PAPR by scramble partitioned sub-blocks into different phases. Fig.1 depicts the scheme of PTS, where the input frequency-domain signal was divided into serval sub-carriers, each of them was conducted with IFFT transform and scrambled with phase factors, then signals in time-domain with minimum PAPR was chosen [17]. The main algorithm of PTS scheme was shown in Fig.2. ...
Partial transmit sequence (PTS) technique is a fairly suitable scheme to mitigate the high peak-to-average power ratio (PAPR) problem inherent in 5G multicarrier system-especially considering high-order QAM modulation design. However, the high computational complexity level and the speed of the convergence for optimizing the phases of the transmitting signal restricts this technique in practical applications. In this paper, a low-complexity frequency domain evaluated PTS (F-PTS) based on spacing multi-objective (SMO) processing algorithm is proposed to reduce the PAPR values. The PAPR performance are accurately predicted in terms of modifying relative dispersion in the frequency domain. As a result, the complexity of searching the optimal phase factors and IFFT computing is simplified. Moreover, frequency domain and time domain evaluating PTS (FTD-PTS) is employed to search the optimal solution within reasonable complexity. Simulation results verify that the F-PTS scheme can obtain well secondary peaks with lower computational complexity, and the FTD-PTS scheme effectively reduces PAPR with a faster convergence speed.
... Along with the pbest, every particle tracked the best solution known as the lbest (local best) or nbest (neighbourhood best), which was derived using the local topology neighbourhood of all particles. This technique was known as a local PSO version [24]. ...
In this paper, we propose a new adaptive layered asymmetrically-clipped optical orthogonal frequency division multiplexing (ALACO-OFDM) technique as a method to improve the spectral efficiency of optical system, especially visible light communication (VLC). Particle swarm optimisation (PSO)-based LACO-OFDM method is used for this purpose and the channel capacities are studied. Simulations using variable layers are carried out to validate the theoretical steps. The simulation results indicate that the ALACO-OFDM technique has significantly improve the spectral efficiency compared to previous techniques such as ACO-OFDM. Moreover, it is shown that channel capacities of different layers are significantly improved when electrical power is increased.
... In [30], presented the amended modified sequence DHT (MSD) system for PAPR reduction and for the preservation of out of band interference (OBI). In [31], the authors presented, a scaled particle swarm optimizations algorithm for finding the best phases in order to diminish the PAPR of the OFDM system. Merah et al. [32] proposed a strategy which depends upon the analyzing the data in the random access memory (RAM). ...
The orthogonal frequency division multiplexing (OFDM) is the most encouraging multi-carrier modulation system chosen for the high data rates but the objective is to resolve intrinsic common issue of peak to average power ratio (PAPR). The projected algorithm is illustrated in this research study which is established upon selected mapping (SLM) with pseudo-random sequence under time domain μ law companding of signal. Besides the significant competitive characteristics of conventional SLM algorithm (ConvenSLM-Algo) (Mestdagh et al. in Electron Lett 32(22):2056–2057, 1996. https://doi.org/10.1049/el:19961384), it undergoes the tedious complexity in generation of phase sequence and for the recovery of sequence, side information is mandatory. The key concern, thus, to eliminate the tedious problem of designing of phase sequence along with the aim of reducing the fluctuation of signal with high PAPR. Henceforth, in the projected algorithm (Projected-Algo) a noteworthy strategy has been investigated and followed for the designing of phase sequence which is very easy and for the recovery of information at receiver, side information of index of column of phase sequences can be used because of straightforwardness in its establishment. Hence, we demonstrate the effective overall excellent performance of Projected-Algo along with analysis and also comparative study of Projected-Algo outperforms the conventional OFDM system (unchanged), ConvenSLM-Algo [16], SLM with new pseudo random phase sequences (ModSLM-Algo) given in literature (Ali et al. in Canadian conference on electrical and computer engineering, 2018. https://doi.org/10.1109/CCECE.2018.8447835).
... In OFDM, Sanjana Prasad and Ramesh Jayabalan [23] were designed a PAPR reduction utilizing scaled PSO created PTS method. A scaled PSO was employed to PTS strategy to choose the phase vectors. ...
... An adaptive mechanism is proposed for reducing the problems by introducing the number of flames (F no ) by Eqn. (23). ...
In high-speed wireless applications, because of the high-speed compatibility of the OFDM, it is a significant signal processing approach. In general, an efficient spectral multi-carrier modulation strategy is named OFDM, which gets impact via the issues of high PAPR. Because of the limited BW availability, the demand for high-speed applications is increasing. Due to the high data requirement, the various subcarriers are increased in OFDM, hence it made the difficult with PAPR (peak-to-average power ratio). To achieve better results by reducing the PAPR is the foremost problem on OFDM. In this paper, a hybrid optimized PTS is used to decrease the PAPR and the data will be encrypted by the DFT based chaotic sequences. A new Hybrid Whale Optimization and Moth Flame Optimization (HWOMFO) is introduced in this paper. It will generate a weighting factor for the PTS. PTS is the foremost strategy in OFDM for reducing the PAPR with low distortion. The minimum performance on computational complexity and PAPR achieved by this paper. The new combination of optimization approaches provides efficient best combination of phase rotational factors. The new hybrid optimization gives fast convergence quality and low complex and also this combination provides better than others. The proposed scheme is executed in MATLAB simulation and performance will be evaluated using parameters such as BER regards to SNR, complementary cumulative distribution function (CCDF) of PAPR and the outputs are associated depends on computation time. However, the experimental results show that compared with existing approaches, our proposed strategy gives better PAPR reduction with respect to SNR.
For fifth‐generation (5G) and beyond 5G communications, filtered nonorthogonal multiple access (F‐NOMA) can be used as a waveform contender. Filtering‐based waveform frameworks provide suppression of out‐of‐band emission (OOBE) and asynchronous transmission. For new types of waveforms, a high peak‐to‐average power ratio (PAPR) remains a challenge. A high PAPR in multicarrier systems can be efficiently mitigated by applying partial transmit sequence (PTS). Combining PAPR reduction techniques can improve the transmission efficiency by nonlinearly scaling the signal amplitudes before transmission and inversely scaling them at the receiver. We propose a hybrid technique that combines PTS and companding to reduce the PAPR in an F‐NOMA system. Conventional nonorthogonal multiple access (NOMA) is compared with F‐NOMA, and systems with and without the hybrid technique are examined regarding metrics including the power spectral density, bit error rate (BER), and computational complexity. Compared with NOMA, simulation results show that F‐NOMA using the proposed technique improves the PAPR and OOBE while preserving the BER performance of F‐NOMA.
