Partial Transmit Sequence Research Articles

PAPR Reduction Techniques and Their BIT Error Rate Measurement at OFDM in LTE System

Orthogonal frequency division multiplexing (OFDM) has become an indispensable part of waveform generation in wideband digital communication since its first appearance in digital audio broadcasting (DAB)and it is indeed in use. These descriptions are simplified version of the detailed descriptions provided by 3gpp. It is a superior technology for the high-speed data rate of wire-line and wireless communication systems. The OFDM has many advantages over other techniques such as its high capacity and immunity against multipath fading channels. However ,one of the main drawbacks of the OFDM system is the high-peak-to-average power ratio (PAPR) that leads the system to produce in-band distortion and out-of-band radiation because of the non-linearity and reduces its efficiency is the distortion of the signal caused at the High Power Amplifier (HPA) of a transmitter . Therefore, it is highly desirable to reduce the PAPR of an OFDM signal. For this, numerous techniques have been proposed to overcome the PAPR problem such as i) selective mapping(SLM) ii) partial transmit sequence (PTS), iii) clipping, iv) clipping and filtering. In this paper, the PTS technique was analytically reviewed as one of the important methods to reduce the high PAPR problem. Simulations are used to analyze the efficiency of the techniques used which signifies OFDM to be providing much better PAPR reduction and a better Bit Error Rate (BER) . From simulation results clipping method shows good PAPR reduction with significant amount of BER degradation. Clipping and filtering method shows slight increase in PAPR with small degradation in BER performance than Clipping method and both methods are computationally less complex. PTS provides good PAPR reduction with high computational complexity.

PAPR Analysis of OFDM using Partial Transmit Sequence Method

Orthogonal Frequency Division Multiplexing (OFDM) is one of the most widely used multicarrier transmission and effective technologies in today's communication networks. OFDM has many benefits and drawbacks. High Peak to Average Power Ratio (PAPR) is one of its main drawbacks. The spectral efficiency of the high-power amplifiers decreases with increasing PAPR. Therefore, maintaining a wireless system's efficiency is required to lower the PAPR. A possible method for lowering the high PAPR in OFDM systems is Partial Transmit Sequence (PTS). PTS generates a number of candidate signals, and the best signal with the lowest PAPR is chosen for transmission. The results shows that the PTS technique achieves greater PAPR minimization with less complexity. MATLAB simulation has been used to examine the OFDM system's PSD, spectral efficiency, BER performance, and PAPR analysis.

Continuous-unconstrained and global optimization for PSO-PTS based PAPR reduction of OFDM signals

Orthogonal frequency division multiplexing (OFDM) is a superior technology for the high-speed data rate of wire-line and wireless communication systems. However, one of the major drawbacks of OFDM signals is the high peak-to-average power ratio (PAPR) problem inherent in 5G waveform design. High PAPR causes OFDM signal distortion in the nonlinear region of the high power amplifier (HPA), and signal distortion leads to a decrease in bit error rate (BER). Partial transmit sequence (PTS) technique is a very attractive technique for PAPR reduction. However, to match the optimum condition on PTS for PAPR reduction, the computational unpredictability and cost of traditional PTS strategy are enormous, thus it is urgent to enhance computational efficiency to obtain the optimal PTS. In this paper, an improved scheme called Continuous-Unconstrained Particle Swarm Optimization based PTS (CUPSO-PTS) technique for optimum phase rotation factors searching is presented. A class of continuous-phase PTS schemes has been proposed to obtain the global optimal phase factor, and the theoretical boundaries can be determined in the continuous-unconstrained searching space. Conversely, when the phase factor values in continuous-unconstrained domain, the equivalent unconstrained PTS optimization can drastically accelerate convergence and reduce total calculation cost. In this paper, we compare the performance of Binary PSO based PTS (BPSO-PTS) scheme and Elitist Genetic Algorithm based PTS (EGA-PTS) scheme for 16-QAM modulation scheme. Theoretical analysis and simulations show that the proposed CUPSO-PTS scheme could provide a significant PAPR reduction in the OFDM system, which outperforms the OFDM systems with the traditional PTS scheme by 0.55 dB at CCDF of 10−3 in PAPR reduction. And 84.74% computational complexity is saved.

PAPR Reduction and Bit Error Rate Evaluation in OFDM System using Hybrid Techniques

Orthogonal frequency division multiplexing (OFDM) has become an important component of waveform generation in wideband transmission. it's a superior technology for the high-speed rate of wired and wireless communication systems. Currently, multiple-input multiple-output orthogonal frequency division multiplexing (MIMO OFDM) systems are crucial wireless communication systems like 4G and 5G networks & tactical communication. The OFDM has many advantages over other techniques like its high capacity and immunity against multipath fading channels. However, one amongst the foremost drawbacks of the OFDM system is that the high-peak-to-average power ratio (PAPR) that leads the system to provide in-band distortion and out-of-band radiation and reduces its efficiency. This problem increases with a rise within the number of transmit antennas. Therefore, it's highly desirable to cut back the PAPR of an OFDM signal. For this, numerous techniques are proposed to beat the PAPR problem like i) Selective mapping (SLM) ii) Partial transmit sequence (PTS), iii) Clipping, iv) Clipping and filtering. All of those are reduced the PAPR by generating alternative subcarrier vector that are statistically independent OFDM symbols for a given data frame and transmitting the symbol with rock bottom peak power. During this paper we also proposed, some hybrid techniques. The hybrid techniques are the technique of clipping is employed in conjunction with SLM and PTS to cut back computational complexity. And also the combination of SLMPTS to scale back PAPR. Simulations are acquainted with analyze the efficiency of the techniques used which signifies OFDM to be providing much better PAPR reduction and a way better Bit Error Rate (BER). it's shown in simulation results that the proposed scheme performs well reducing PAPR. But the proposed scheme is more complex than the prevailing techniques.

Side information embedding scheme for PTS based PAPR reduction in OFDM systems

Partial transmit sequence (PTS) is one of the well-known probabilistic schemes in reducing peak-to-average power ratio (PAPR) for orthogonal frequency division multiplexing (OFDM) signal. In our paper, we address the two major concerns of the PTS–OFDM system: side information (SI) free transmission from transmitter end and complexity reduction of the generated candidates. In the proposed scheme, side information is embedded on the locations of higher power subcarriers at specific partitions within the data block and at the receiver side extraction of SI is based on the power disparity among data symbols in the partitions. The error performance of the proposed scheme over the AWGN channel is analyzed mathematically. Besides, time efficiency of the proposed algorithm has been estimated in respect of computations required for finding the optimal candidates. Simulation results confirm that our proposed SI free transmission scheme performs well in terms of low BER degradations over the AWGN and Rayleigh fading channels, better SI error detection probability, lesser computations and improved PAPR reductions of the OFDM signals.

Comprehensive probabilistic analysis of PAPR reduction approach with localized mapping

In recent years, OFDMA plays a vital role in current day communications and drastically used in mobile technologies. The Maximum to Expected Power Ratio is key element in transmitter to reduce their ratio using PAPR reduction techniques needed to improve the quality of performance. The localized mapping in implemented in OFDMA and gives greater improvement in reduction of PAPR which improves the performance. The next generation communication needs versatile technologies to develop their performance in order to achieve the good quality of service. The probabilistic approach like Selective Mapping (SLM) and Partial Transmit Sequence (PTS) are proposed in Localized –OFDMA in order to give better solution. In this paper, the proposed approach L-PTS outperforms the L-SLM and better trade-off the power ratio with error rate.

Filtered OFDM PAPR performance for 5G communications is improved utilizing PTS

A waveform candidate for fifth-generation (5G) communications has been recommended: the filtered orthogonal frequency division multiplexing (F-OFDM) system. Filtering-based waveform frameworks are distinguished by the suppression of out-of-band emission (OOBE) and asynchronous transmission. As a result, the new waveform candidates are still struggling with the PAPR issue. In multicarrier systems, partial transmit sequence (PTS) is an efficient way to combat the rising tendency of PAPR. The high PAPR value of an F-OFDM system is reduced using the PTS technique in this study. The OFDM system is then put up against this one. Other relevant metrics, such as frequency localization, bit error rate (BER), and computational complexity, are evaluated and analysed in both systems with and without PTS. According to simulation studies, F-OFDM based on PTS provides better PAPR, BER, and OOBE than OFDM. F-BER OFDM's is unaffected by the PTS technique's implementation.

Hybrid-Domain Evaluation PTS with Adaptive Selection Methods for PAPR Reduction

The 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 systems, especially considering a 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 restrict this technique in practical applications. In this paper, a low-complexity frequency-domain-evaluated PTS (F-PTS) based on a spacing multiobjective (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, a frequency-domain- and time-domain-evaluating PTS (FTD-PTS) is employed to search the optimal solution with a reasonable complexity. Simulation results verify that the operation rate of F-PTS is significantly improved after transferring the exhaustive search strategy of PTS into the SMO algorithm, and the F-PTS PAPR reduction performance is just 0.3 dB away from theoretical optimal performance. The FTD-PTS spends an acceptable operation rate to obtain optimal PAPR reduction performance, which subtracts 0.5 and 0.6 dB more than PSO-PTS and conventional PTS at CCDF=10−3, respectively.

Analysis of peak-to-average power ratio in filter bank multicarrier with offset quadrature amplitude modulation systems using partial transmit sequence with shuffled frog leap optimization technique

<p class="Abstract">Because of its low adjacent channel leakage ratio, the Filter Bank Multicarrier with Offset Quadrature Amplitude Modulation (FBMC-OQAM) has sparked the attention of many researchers in recent times. However, the problem of high Peak-to-Average Power Ratio (PAPR) measurement has a detrimental influence upon the FBMC system's energy measurement efficiency. We study PAPR reduction of FBMC-OQAM signals using the Partial Transmit Sequence (PTS) methods in this work. The PTS with shuffled frog leap phase optimization method is proposed in this paper to reduce the larger PAPR measurement, which is the major disadvantage of the filter bank multicarrier with offset quadrature amplitude modulation system. According to the simulation software findings, the suggested approach has a considerably superior PAPR, which may reduce the PAPR by about 2 dB at complementary cumulative distribution function 10<sup>-3</sup> when compared to the traditional PTS method, and it has a much lower computational complexity than the previous ways. The experimental parameters are measured, and results are evaluated using MATLAB tool.</p>

Particle Swarm Optimization-based dummy sub-carriers insertion for peak to average power ratio reduction in OFDM systems

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.

Adaptive PTS scheme based on fuzzy neural network for PAPR reduction in OFDM system

High peak-to-average power ratio (PAPR) is one of the major drawbacks of orthogonal frequency division multiplexing (OFDM) communication system, which causes signal distortion and affects communication performance. Partial transmission sequence (PTS) is an effective method to reduce the PAPR, but it cannot adaptively select processing parameters for the signal and has high computational complexity. Aiming at the defects of PTS method, this paper propose an adaptive PTS method based on fuzzy neural network (FNN-APTS). The method considers the signal and system characteristics, combining the learning ability of the neural network with the reasoning ability of the fuzzy control method, to select the processing parameters for the signal adaptively. The simulation results show that the proposed FNN-APTS method can adapt to different OFDM models, reducing the computational complexity and improving the system performance while ensuring the reasonable PAPR.

An Intelligent Detoxification Function of Liver Algorithm-Partial Transmit Sequence (IDFLA-PTS) for the Reduction of Peak to Average Power Ratio in Underwater Acoustic OFDM Communication

Intelligent algorithms in artificial intelligence have brought several benefits to digital signal processing. The boom in machine learning and intelligent systems provides new perspectives and methods to solve many research problems in Underwater Acoustic (UWA) Orthogonal Frequency Divisional Multiplexing (OFDM) communication. Partial transmit sequence is a tremendous technique for the mitigation of high Peak-to-Average Power Ratio (PAPR) in OFDM communication systems, but finding the optimum phase factors has still a few problems. In this paper, a Partial Transmit Sequence (PTS) based on an Intelligent Detoxification Function of Liver Algorithm-Partial Transmit Sequence (IDFLA-PTS) is proposed for the mitigation of PAPR in the UWA OFDM communication systems. This algorithm reduces the PAPR and the complexity of the proposed UWA OFDM model. The IDFLA-PTS is also compared with the Genetic Algorithm-Partial Transmit Sequence (GA-PTS). Besides this, the Bit Error Rate (BER) performance of the IDFLA-PTS is shown when a High Power Amplifier (HPA) is used for the BELLHOP channel model. The experimental results of the proposed IDFLA-PTS method achieved nearly optimum results with fair complexity as compared to GA-PTS and boosted the BER performance.

PAPR Reduction of NOMA Using Vandermonde Matrix-Particle Transmission Sequence

Non-Orthogonal Multiple Access (NOMA) is an ideal choice for 5G waveforms due to their characteristics such as high data rate, massive device connectivity, high spectral access, and effective frequency selective fading. Thus, it permits gigantic connectivity. The spectrum overlaps with NOMA, which consents several operators to segment the spectrum at the same frequency. These features make NOMA more suitable for use beyond 5G. Peak to Average Power (PAPR) is a major problem in Multi-Carrier Techniques (MCT) like NOMA and it also degrades the performance of the amplifier. The Partial Transmission Sequence (PTS) is a superior algorithm for moderating the PAPR. However, it also increases the complexity of the structure. The PAPR is reduced in NOMA by multiplying the NOMA signal with optimised phase vectors (P). The phase vectors are generated by using the Vandermonde Matrix (VM). In this work, we proposed a VM-PTS algorithm for the NOMA system, and the number of computations to search the optimal phase vectors for NOMA high PAPR signal is less as compared with existing PTS. The outcomes demonstrate that the performance of the recommended PTS in terms of PAPR, Bit Error Rate (BER), and complexity is better than the conventional PTS (C-PTS).

Performance Analysis of PTS PAPR Reduction Method for NOMA Waveform

Cellular systems utilize single and multicarrier waveforms for high-speed data transmission. The Fifth-Generation (5G) system proposes several techniques based on multicarrier waveforms. However, the Peak to Average Power Ratio (PAPR) is one of the significant concerns in advanced waveforms as it degrades the framework's efficiency. Non Orthogonal Multiple Access (NOMA) can provide massive connectivity, which is the crucial requirement of the Internet of Things (IoT). The 3rd generation tested NOMA applications in downlink and uplink transmission. However, NOMA uplink transmission in the power domain has performance degradation and is not considered a possible technique in 3rd generation power projects (3GPP). Presently, NOMA is not just a concept but has been introduced as a standard method in various transmission schemes. NOMA suffers from a high peak to average power ratio (PAPR), which forces the power amplifier (PA) to shift into a nonlinear region. The high value of PAPR leads the power amplifier of the multicarrier technique into a nonlinear region. As the performance of the power amplifier degrades, the overall system performance goes down. In this work, we suggest different methods to overcome the issue of PAPR in multicarrier techniques such as Selective Mapping (SLM) and Partial Transmit Sequence (PTS). The simulation results reveal that the performance of the proposed PTS is better than that of the conventional SLM and PTS.

A Novel Peak-to-Average Power Ratio Reduction for 5G Advanced Waveforms

Multi and single carrier waveforms are utilized in cellular systems for high-speed data transmission. In The Fifth Generation (5G) system, several waveform techniques based on multi carrier waveforms are proposed. However, the Peak to Average Power Ratio (PAPR) is seen as one of the significant concerns in advanced waveforms as it degrades the efficiency of the framework. The proposed article documents the study, progress, and implementation of PAPR reduction algorithms for the 5G radio framework. We compare the PAPR algorithm performance for advanced and conventional waveforms. The simulation results reveal that the advanced Partial Transmission Sequence (PTS) and Selective Mapping (SLM) methods enhanced the throughput and gain of the 5G waveforms. Furthermore, we have also analyzed the performance of Orthogonal Time Frequency Space Modulation (OTFSM) based on a single carrier system and found that PAPR is significantly low and is best suited to fading environments. It is seen that the conventional algorithms lower the PAPR but increase the complexity. The proposed PTS and SLM have shown good performance with low computational complexity.

Minimizing the PAPR for FBMC/OQAM Signals Using Enhanced-PTS with Low Complexity Search

The filter bank multicarrier with offset quadrature amplitude modulation (FBMC/OQAM) scheme has recently become a focus of interest for many scholars and researchers. Despite its impressive advantages over Orthogonal Frequency Division Multiplexing (OFDM), the FBMC/OQAM system exhibits high Peak-to-Average Power Ratio (PAPR) which could plague its performance if it is not properly managed. In this paper, we proposed a PAPR reduction scheme that improves the Partial Transmit Sequence (PTS) to an enhanced PTS (EPTS), then employs a low complexity search to determine the optimal combination of phase factors. In the enhanced PTS, the FBMC/OQAM data blocks are partitioned into sub-blocks by taking into account their overlapping arrangement, then a segmentation operation is performed to the overall overlapping partitioned data blocks in order to form several segments of sub-blocks. After that, the segments are optimized consecutively by applying a phase factor search approach. Referred to as enhanced PTS with iterative flipping (EPTS-IF), the proposed scheme optimizes consecutively the segments of sub-blocks by employing Iterative Flipping approach. The PAPR reduction performance and the computational complexity of the proposed scheme have been evaluated through computer simulations and theoretical analysis which revealed a significant PAPR reduction gain of approximately 30.48%, and at a low computational cost.

PAPR Reduction Using Advanced Partial Transmission Scheme for 5G Waveforms

The implementation of Peak Average to Power Ratio (PAPR) reduction technologies will play an important role in the regularization of Fifth Generation (5G) radio communication. PAPR reduction in the advanced waveform will be the key part of designing a 5G network for different applications. This work introduces the simulation of an Advanced Partial Transmission Sequence (A-PTS) reduction techniques for Orthogonal Frequency Division Multiplexing (OFDM) and Filter Bank Multi-Carrier (FBMC) transmission schemes. In the projected A-PTS, the FBMC signals are mapped into the number of sub-blocks and Inverse Fast Fourier transform (IFFT) is performed to estimate the high peak power in the time domain. The FBMC sub-blocks are multiplied with the phase elements to achieve an optimal PAPR value. A MATLAB 2014v simulation is used to estimate the PAPR, Bit Error Rate (BER), Error Vector Magnitude (EVM), and Modulation Error Rate (MER) performance of the proposed reduction schemes. The simulated result reveals that the performance of the projected algorithm is better than the conventional algorithms.

Precoded SLM and PTS Scheme for Reduced PAPR in OFDM for Wireless Communications

Orthogonal Frequency Division Multiplexing (OFDM) contribute high data rates in current as well as future wireless communication systems but it aches from high Peak to Average Power Ratio (PAPR). But this high PAPR makes the High-Power Amplifier (HPA) complex which increases the cost of it and leads to the drawbacks like Inter Carrier Interference (ICI) and rise in out of band radiation. Even though many techniques are there to decrease the complexity of HPA by reducing the PAPR, Selected Mapping (SLM) and the Partial Transmit Sequence (PTS) provides less PAPR with low complexity. In this paper, both PTS and SLM are combined with Discrete Sine Transform (DST) and their PAPR and efficiencies are also compared with OFDM signal. The proposed hybrid DST-PTS and DST-SLM provides less PAPR compared to OFDM, SLM and PTS techniques with low complexity. Also, the bit error rate for DST-SLM and DST-PTS techniques are compared for different values of SNR. In future wireless communication systems, these proposed techniques can be used as they provide less bit error rate and less PAPR with low complexity

Partial transmit sequence based on discrete particle swarm optimization with threshold about PAPR reduction in FBMC/OQAM system

Partial transmit sequence (PTS) is an effective method to reduce the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) system, but it is not suitable for the filter bank multi-carrier with offset quadrature amplitude modulation (FBMC/OQAM) system because of the overlapping structure of FBMC/OQAM signals. And PTS needs the traversal method to search for the optimal solution, which will increase the complexity of the system. To overcome this shortcoming, a PTS based on discrete particle swarm optimization with threshold (PTS-DPSO-TH) is proposed and applied to FBMC/OQAM system in this paper. PTS-DPSO-TH uses discrete particle swarm optimization (DPSO) to search for the optimal solution, effectively reducing the excessively high PAPR of the FBMC/OQAM system and avoiding the increase of system complexity. Secondly, the threshold is introduced to decrease the number of iterations and further reduce the system's complexity on the premise of guaranteeing the performance of PAPR reduction. Furthermore, through simulation, the effects of multiple parameters on PAPR reduction performance of PTS-DPSO-TH are compared and analysed.

PAPR Reduction in OFDM Systems Using Hybrid Zadoff-Chu Transform Precoding and Partial Transmit Sequence

Orthogonal Frequency Division Multiplexing (OFDM) is a multicarrier modulation (MCM) scheme that plays a significant role in digital wireless communication. As a result of its high data rate capability and immunity to multipath fading effect, among others, OFDM remains an ideal technology for 5G communication systems and beyond. Unfortunately, a major drawback of this technology is the high peak-to-average power ratio (PAPR). Nevertheless, many techniques for reducing PAPR have been proposed in the past to address this problem. However, all the techniques previously used have limitations such as high computational complexity, data rate loss, high signal distortion, increase in bandwidth, increase in transmit power, and memory requirements. In this paper, a hybrid technique that combines Zadoff-Chu Transform (ZCT) precoding and Partial Transmit Sequence (PTS) for reducing high PAPR in OFDM signals is presented. To reduce the data rate loss and computational complexity in PTS when a large subblock is used, a Zadoff-Chu precoding is applied to OFDM symbols to precode the symbol before applying PTS with a fewer number of subblocks. An OFDM model was developed where ZCT and PTS techniques were implemented. The performance of the hybrid model was analyzed using Power Spectral Density (PSD), Complementary Cumulative Distribution Function (CCDF), and Bit Error Rate (BER). The simulation result indicates that the hybrid ZCT-PTS provides a better result than using either Zadoff-Chu precoding technique or Partial Transmit Sequence technique separately. A PAPR of 4.2 dB and BER of 3dB is achieved for hybrid ZCT-PTS. The hybrid technique provides a better system performance when compared with Conventional OFDM systems.