Tone Reservation Scheme Research Articles

Per Sub-band Tone Reservation Scheme for Universal Filtered Multi-Carrier Signal

Per Sub-band Tone Reservation Scheme for Universal Filtered Multi-Carrier Signal

A Novel Low Complexity Two-Stage Tone Reservation Scheme for PAPR Reduction in OFDM Systems.

Orthogonal frequency division multiplexing (OFDM) has the characteristics of high spectrum efficiency and excellent anti-multipath interference ability. It is the most popular and mature technology currently in wireless communication. However, OFDM is a multi-carrier system, which inevitably has the problem of a high peak-to-average power ratio (PAPR), and s signal with too high PAPR is prone to distortion when passing through an amplifier due to nonlinearity. To address the troubles caused by high PAPR, we proposed an improved tone reservation (I-TR) algorithm to alleviate the above native phenomenon, which will pay some modest pre-calculations to estimate the rough proportion of peak reduction tone (PRT) to determine the appropriate output power allocation threshold then utilize a few iterations to converge to the near-optimal PAPR. Furthermore, our proposed scheme significantly outperforms previous works in terms of PAPR performance and computational complexity, such as selective mapping (SLM), partial transmission sequence (PTS), TR, tone injection (TI), etc. The simulation results show that in our proposed scheme, the PAPR is appreciably reduced by about 6.44 dB compared with the original OFDM technique at complementary cumulative distribution function (CCDF) equal to 10-3, and the complexity of I-TR has reduced by approximately 96% compared to TR. Besides, as for bit error rate (BER), our proposed method always outperforms the original OFDM without any sacrifice.

A novel differential evolution algorithm for tone reservation based peak to average power ratio reduction technique in orthogonal frequency division multiplexing systems

A critical problem in the Orthogonal Frequency Division Multiplexing (OFDM) framework for 5G communication is the high Peak to Average Power Ratio (PAPR) of the transmitted signal. The Tone Reservation (TR) scheme is employed to minimize the OFDM signal’s PAPR in time domain. It is comprised of some reserved subcarriers to generate a Peak Reduction Tone (PRT) set. The selection of these PRT set and the optimal target clipping level are the depending parameters of the PAPR reduction performance. A novel Differential Evolution based Tone Reservation (DE-TR) scheme is proposed to find an optimal PRT set and then the PAPR is reduced by employing an Optimized Iterative Clipping and Filtering (OICF) technique. Compared to other related techniques like Clipping Control Tone Reservation (CC-TR), Curve Fitting based Tone Reservation (CF-TR) and Parallel Tabu Search Tone Reservation (PTS-TR), the proposed technique DE-TR(Pro.) contributes to a substantial PAPR reduction output with lower computational complexity and maintaining an adequate bit error rate (BER) and spectral spreading efficiency. In addition, the theoretical relationship between the Error Vector Magnitude (EVM) and PAPR as well as CCDF performance with EVM are analyzed.

Hybrid Energy Efficiency Friendly Frequency Domain TR Algorithm Based on PSO Algorithm Evaluated by Novel Maximizing HPA Efficiency Evaluation Criteria

Smart Grids (SGs) expedite secure, large-scale and efficient two-way communication between the power supply and management, but under a sophisticated 5G communication infrastructure, the multi carrier system is the principle system. The high peak-to-average power ratio (PAPR) is one of the significant limitations of the 5G multi carrier (MC) system, as it impedes the efficient design of the 5G analogue front end. Tone reservation (TR) is a highly efficient scheme without signal distortion, which is designed by increasing the freedom in the frequency domain for PAPR reduction. In this paper, a particle swarm optimization (PSO) based TR (PSO-TR) scheme proceeding with an optimal input power back off-modulation error ratio (IBO-MER) convergence criterion is proposed to improve high power amplifier (HPA) efficiency for OFDM systems. A probabilistic analysis of TR predistribution and freedom in the frequency domain, in relationship with the amplitude of its constituent samples, is carried out. This yields the theoretical framework employed in design of the proposed high computing-enhanced solutions. The proposed PSO-TR essentially make the frequency domain distribution and operation itself adaptive, that is, it adjusts to comply with the changing HPA efficiency and redundant cost during application runtime.

Cyclic Shift Based Tone Reservation PAPR Reduction Scheme with Embedding Side Information for FBMC-OQAM Systems

The tone reservation (TR) scheme is an attractive method to reduce peak-to-average power ratio (PAPR) in the filter bank multicarrier with offset quadrature amplitude modulation (FBMC-OQAM) systems. However, the high PAPR of FBMC signal will severely degrades system performance. To address this issue, a cyclic shift based TR (CS-TR) scheme with embedding side information (SI) is proposed to reduce the PAPR of FBMC signals. At the transmitter, four candidate signals are first generated based on cyclic shift of the output of inverse discrete Fourier transform (IDFT), and the SI of the selected signal with minimum peak power among the four candidate signals is embedded in sparse symbols with quadrature phase-shift keying constellation. Then, the TR weighted by optimal scaling factor is employed to further reduce PAPR of the selected signal. At the receiver, a reliable SI detector is presented by determining the phase rotation of SI embedding symbols, and the transmitted data blocks can be correctly demodulated according to the detected SI. Simulation results show that the proposed scheme significantly outperforms the existing TR schemes in both PAPR reduction and bit error rate (BER) performances. In addition, the proposed scheme with detected SI can achieve the same BER performance compared to the one with perfect SI.

Enhancing PAPR reduction for FBMC-OQAM systems by joint both tone reservation and companding methods

<span>One of the major problems that faces any wireless communication system that apply multicarrier modulation technology is large Peak-to-Average 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 based on combining tone reservation and companding techniques for FBMC-OQAM systems. The simulation results show that the new scheme (TR&Compd) presents better result in term of PAPR reduction compared to TR and Companding methods taken separately.</span>

Extreme Learning Machine-Based Tone Reservation Scheme for OFDM Systems

One of the limitations of the Neural Network-based peak-to-average power ratio (PAPR) reduction methods lies in the long-term training process through a large amount of training data. To address this issue, an extreme learning machine-based (ELM) tone reservation scheme is proposed, which could achieve comparable PAPR performance with low complexity compared to other Neural Network-based algorithms. An ELM-based mapper, trained on the clipping control tone reservation (CC-TR) signals, is designed to reduce the PAPR of orthogonal frequency division multiplexing (OFDM) system. Simulation results indicate that the proposed algorithm owns the advantages of fast learning capability and short training length.

A Novel Tone Reservation Scheme Based on Deep Learning for PAPR Reduction in OFDM Systems

A major defect of orthogonal frequency division multiplexing (OFDM) systems is the high peak-to-average power ratio (PAPR). In this letter, a novel scheme based on deep leaning, called tone reservation network (TRNet), is proposed for OFDM systems to improve the performance of the tone reservation (TR) technique. More specifically, TRNet reserves a part of tones to generate a peak-canceling signal. The feedforward neural network is used to adaptively generate a peak-canceling signal according to the characteristics of the input signal. Computer simulation results show that the proposed scheme provides a better PAPR reduction performance with fewer reserved tones, which is also beneficial to improve the bandwidth efficiency.

Low-Complexity Tone Reservation Scheme Using Pre-Generated Peak-Canceling Signals

In this letter, an improved tone reservation (TR) algorithm using pre-generated peak-canceling signals is proposed. The proposed algorithm generates and saves peak-canceling signals in the pre-work so that they can be used directly at runtime. The proposed algorithm does not need to iterate, and it can be implemented with $\boldsymbol {O(N)}$ computational complexity ( $\boldsymbol {N}$ is the number of subcarriers). The simulations indicate that the proposed algorithm achieves about 3.5 dB peak-to-average power ratio (PAPR) reduction at complementary cumulative distribution function (CCDF) of $\boldsymbol {10^{-3}}$ while retaining satisfactory bit error rate (BER) and spectral spreading performance.

SCR-Based Tone Reservation Schemes With Fast Convergence for PAPR Reduction in OFDM System

The signal to clipping noise ratio (SCR)-based tone reservation scheme is a promising candidate for peak-to-average ratio (PAPR) reduction of orthogonal frequency division multiplexing signals, but it suffers from low convergence rate caused by the nonoptimal scalar scaling factor. In this letter, we first derive a scaling SCR (S-SCR) scheme, in which the scaling factor is an optimized vector with peak regeneration constraints. To further improve convergence rate and eliminate multiple peaks in each iteration, we then propose the multiple scaling SCR (MS-SCR) scheme with an augmented scaling factor in matrix form. Numerical results demonstrate the superiority of proposed schemes compared with the conventional ones, including better PAPR reduction performance with fewer iterations and comparable bit error ratio performance. Furthermore, the computational complexity reduction ratio of the proposed S-SCR and MS-SCR schemes are increased by 38.52% and 27.36%, respectively.

An Adaptive Tone Reservation Scheme for PAPR Reduction of OFDM Signals

An Adaptive Tone Reservation Scheme for PAPR Reduction of OFDM Signals

Sparse PTS scheme based on TR schemes for PAPR reduction in FBMC‐OQAM systems

The filter bank multicarrier with offset quadrature amplitude modulation (FBMC-OQAM) has aroused widespread concern in the 5G communication. However, FBMC-OQAM has an inherent drawback of high peak-to-average power ratio (PAPR) that should be mitigated. Here, the authors propose an efficient hybrid scheme based on sparse partial transmit sequence (sparse PTS) scheme and tone reservation (TR) scheme to reduce the PAPR in FBMC-OQAM systems. The first step is to detect and record the location of peak of FBMC-OQAM signals and adopt phase rotation factors (based on PTS) to directly optimise the phase of recorded peak signals, which is called sparse PTS. Then the result is further processed by TR scheme for PAPR reduction. Simulation results show that the proposed hybrid scheme provides better PAPR reduction performance than the two schemes, and can achieve less side information transmitted than the sparse PTS scheme.

Joint optimization of PAPR reduction based on modified TR scheme for MIMO-OFDM radar

In this paper, we propose a joint optimization method to reduce peak-to-average power ratio (PAPR) for multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) radar systems, based on the modified tone-reservation (TR) scheme which has sufficient degree of freedom to satisfy some special and meaningful waveform design criteria. In terms of applying independent or concurrent reserved subcarrier weights for transmit antennas, we provide two PAPR reduction schemes respectively, i.e., independent TR (ITR) and concurrent TR (CTR). It is demonstrated that the proposed joint optimization method can effectively reduce the PAPR to an acceptable threshold and is superior to the conventional methods. Note that the optimized OFDM waveforms for MIMO radar can avoid the grating-lobes in distance domain. Simulation results are presented to verify the derivations.

A novel peak-to-average power ratio reduction scheme via tone reservation in OFDM systems

In this paper, a novel signal-to-clipping noise ratio and least squares approximation tone reservation scheme (SCR-LSA TR) is proposed to reduce the peak-to-average power ratio for orthogonal frequency division multiplexing systems. During the SCR procedure, only the element with the maximal amplitude is picked for processing, which not only decreases the algorithm complexity, but also helps to overcome the BER deterioration. With the LSA method, the amplitude of the peak-cancelling signals can approximate to that of the original clipping noise as much as possible. Through the combination of the optimization factor in the LSA method, the classic SCR method can achieve better PAPR reduction with faster convergence. Simulation results show that the proposed SCR-LSA TR scheme has less in-band distortion and smaller out-of-band spectral radiation. The BER of the proposed scheme shows a better performance especially under the 16-QAM over the additive white Gaussian noise channel.

PAPR reduction based on tone reservation scheme for DCO-OFDM indoor visible light communications.

High peak-to-average power ratio (PAPR) leads to out-of-band power and in-band distortion in the direct current-biased optical orthogonal frequency division multiplexing (DCO-OFDM) systems. In order to effectively reduce the PAPR with faster convergence and lower complexity, this paper proposes a tone reservation based scheme, which is the combination of the signal-to-clipping noise ratio (SCR) procedure and the least squares approximation (LSA) procedure. In the proposed scheme, the transmitter of the DCO-OFDM indoor visible light communication (VLC) system is designed to transform the PAPR reduced signal into real-valued positive OFDM signal without doubling the transmission bandwidth. Moreover, the communication distance and the light emitting diode (LED) irradiance angle are taking into consideration in the evaluation of the system bit error rate (BER). The PAPR reduction efficiency of the proposed scheme is remarkable for DCO-OFDM indoor VLC systems.

A Novel Adaptive Tone Reservation Scheme for PAPR Reduction in Large-Scale Multi-User MIMO-OFDM Systems

In this letter, a novel adaptive tone reservation (ATR) scheme is proposed for the orthogonal frequency division multiplexing-based large-scale multiuser multiple-input multiple-output systems to deal with the inherent peak-to-average power ratio (PAPR) problem. The key idea of the proposed ATR scheme is to iteratively perform the tone reservation (TR) scheme on the antenna with the maximum PAPR. Simulation results validate that the ATR scheme offers better PAPR reduction performance and lower computational complexity than the conventional TR scheme.

Hybrid PAPR Reduction Scheme for FBMC/OQAM Systems Based on Multi Data Block PTS and TR Methods

The filter bank multicarrier with offset quadrature amplitude modulation (FBMC/OQAM) is being studied by many researchers as a key enabler for the fifth-generation air interface. In this paper, a hybrid peak-to-average power ratio (PAPR) reduction scheme is proposed for FBMC/OQAM signals by utilizing multi data block partial transmit sequence (PTS) and tone reservation (TR). In the hybrid PTS-TR scheme, the data blocks signal is divided into several segments, and the number of data blocks in each segment is determined by the overlapping factor. In each segment, we select the optimal data block to transmit and jointly consider the adjacent overlapped data block to achieve minimum signal power. Then, the peak reduction tones are utilized to cancel the peaks of the segment FBMC/OQAM signals. Simulation results and analysis show that the proposed hybrid PTS-TR scheme could provide better PAPR reduction than conventional PTS and TR schemes in FBMC/OQAM systems. Furthermore, we propose another multi data block hybrid PTS-TR scheme by exploiting the adjacent multi overlapped data blocks, called as the multi hybrid (M-hybrid) scheme. Simulation results show that the M-hybrid scheme can achieve about 0.2-dB PAPR performance better than the hybrid PTS-TR scheme.

A Novel Multi-Block Tone Reservation Scheme for PAPR Reduction in OQAM-OFDM Systems

Due to the overlapping structure of the offset quadrature amplitude modulation-based orthogonal frequency-division multiplexing (OQAM-OFDM) signals, the peak-to-average power ratio (PAPR) in OQAM-OFDM systems cannot be efficiently reduced by existing PAPR reduction methods, which independently consider the PAPR reduction in each data block. In this paper, a novel multiblock tone reservation (MB-TR ) scheme is proposed for the PAPR reduction in OQAM-OFDM systems. The key idea of the MB-TR scheme is to exploit the overlapping structure of the OQAM-OFDM signals and jointly consider the adjacent data blocks to obtain the clipping noise. To effectively eliminate the peaks of the OQAM-OFDM signals, the MB-TR scheme generates the peak-canceling signal by employing the weighted least square algorithm to fit the waveform of the peak-canceling signal to the waveform of clipping noise. Simulation results and analysis show that the MB-TR scheme could offer better PAPR reduction with lower computational complexity than the clipping control tone reservation scheme directly employed in OQAM-OFDM systems.

A Low Complexity Tone Reservation Scheme Based on Time-Domain Kernel Matrix for PAPR Reduction in OFDM Systems

The peak-to-average power ratio (PAPR) problem is a main challenge for orthogonal frequency division multiplexing systems. In this paper, the proposed scheme reduces the PAPR with low complexity, by utilizing the time-domain kernel matrix to generate the peak reduction signals. With the time-domain kernel generated only once or offline, there are no IFFT/FFT operations in the peak reduction iterations. Also, we performed simulations and results indicated that the algorithm converges to the threshold in about three iterations, so the hardware complexity and time complexity of this scheme are relatively low to achieve a comparable peak reduction as some other tone reservation schemes.

An Improved Tone Reservation Scheme in OFDM Systems for Adaptive Amplitude Clipping

Orthogonal frequency division multiplexing(OFDM) suffers from a high peak to average power ratio(PAPR). Tone reservation (TR) technology is considered as one of the most promising methods because of no additional distortion, no side information, and low implementation cost. However, in all PAPR reduction schemes，determining the optimal target clipping level is difficult. In this paper, we consider an adaptive amplitude least squares approximation(AALAS-TR) algorithm. Adjust adaptive optimal convergence factor for initial clipping threshold. That is results an approximately PAPR reduction performance with a low computational complexity. Simulation results show that the proposed algorithm can achieve better PAPR reduction as that different clipping threshold .