Universal Filtered Multicarrier Waveform Research Articles

A Novel Concatenated LWT and WHT Based UFMC Waveform Design for the Next Generation Wireless Communication Systems

A novel concatenated Lifting Wavelet Transform (LWT) and Walsh Hadamard Transform (WHT) with Universal Filtered Multi Carrier (UFMC) waveform is suggested as an alternative to Orthogonal Frequency Division Multiplexing (OFDM) waveform for the next generation wireless telecommunication systems in this paper. The suggested waveform is composed of LWT and WHT with UFMC waveform. Both the elimination the disadvantages of OFDM and the improvement the achievement of UFMC waveform, from the fifth generation waveform candidates, has been aimed with the suggested waveform. In order to verify the performance of the suggested waveform and compare with the traditional OFDM, UFMC, and LWT‐UFMC waveform computer simulation studies are performed in additive white Gaussian noise and flat Rayleigh fading channel environments. The acquired computer simulation results exhibit that the achievement of the suggested waveform has better than the achievement of the traditional OFDM, UFMC, and LWT‐UFMC waveform. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

UFMC Waveform and Multiple-Access Techniques for 5G RadCom

In recent years, multiple functions traditionally realized by hardware components have been replaced by digital-signal processing, making radar and wireless communication technologies more similar. A joint radar and communication system, referred to as a RadCom system, was proposed to overcome the drawbacks of the conventional existent radar techniques while using the same system for intervehicular communication. Consequently, this system enhances used spectral resources. Conventional orthogonal frequency division multiplexing (OFDM) was proposed as a RadCom waveform. However, due to OFDM’s multiple shortcomings, we propose universal filtered multicarrier (UFMC), a new 5G waveform candidate, as a RadCom waveform that offers a good trade-off between performance and complexity. In addition to that, we propose multicarrier code division multiple access (MC-CDMA) as a multiple-access (MA) technique that can offer great performance in terms of multiuser detection and power efficiency. Moreover, we study how UFMC filter length and MC-CDMA spreading sequences can impact overall performance on both radar and communication separately under a multipath channel. Analysis of the bit error rate (BER) of the UFMC waveform was performed in order to confirm the experiment results.

A novel discrete elephant herding optimization-based PTS scheme to reduce the PAPR of universal filtered multicarrier signal

The recently proposed waveform called universal filtered multicarrier (UFMC) has already managed to get the attention of science world due to its superior features and it has been accepted as one of the foremost fifth generation (5G) waveform contenders. However, due to being a type of multicarrier waveform, the UFMC suffers from the problem of high peak-to-average power ratio (PAPR). In this paper, a new discrete elephant herding optimization-based partial transmit sequence (DEHO-PTS) scheme is suggested to reduce the PAPR of UFMC signals to minimum levels. Due to the fact that the optimization of phase rotation factors multiplied by the sub-blocks in the conventional partial transmit sequence (PTS) technique is a combinatorial optimization problem to be solved in discrete space, in order to integrate the elephant herding optimization (EHO) algorithm into the PTS scheme, we developed its discrete version (DEHO) in this paper. In the simulations, the capability of the suggested DEHO-PTS procedure to minimize the PAPR, suppress the out-of-band emission and decrease the bit error rate of the UFMC signal amplified via a nonlinear high power amplifier was analyzed. Simulation results clearly indicate that our proposed DEHO-PTS procedure can be a serious option for UFMC waveform to minimize the PAPR values of transmission signals due to its significant PAPR reduction, side lobe suppression and bit error rate performances with low computational complexity.

Advanced SLM scheme based on discrete forest optimization algorithm for PAPR minimization in UFMC waveform

Inherent multicarrier transmission mechanism of the universal filtered multicarrier (UFMC) waveform engenders the problem of high peak-to-average power ratio (PAPR). Since it is impossible for a nonlinear high power amplifier (HPA) to execute a distortionless amplification unless the PAPR of transmission signal is below an acceptable level, eliminating the aforementioned PAPR drawback in UFMC waveform is so critical for smooth communication. With this in mind, we developed a new selective mapping (SLM) scheme based on discrete forest optimization algorithm (DFOA) for the UFMC waveform. The related scheme was created by embedding the DFOA into the conventional SLM with the intention of optimizing the values of phase factors by which the phase rotation process is carried out in frequency domain to reduce the PAPR of eventual time domain signal attained from the SLM output. It is confirmed via the simulations that, remarkable PAPR improvements are achieved through the DFOA-SLM scheme in the UFMC signal thanks to the DFOA-supported search for the optimal sequence of phase factors instead of classical random search strategy inherent in the conventional SLM method.

PAPR reduction using selective mapping scheme in universal filtered multicarrier waveform

In this paper, the selective mapping (SLM) technique possessing the powerful and distortionless peak to average power ratio (PAPR) reduction capability was employed in universal filtered multicarrier (UFMC) waveform that is considered as one of the most promising fifth generation (5G) waveform candidates in order to provide a solution to the PAPR issue encountered in the related waveform. Owing to our SLM-based PAPR reduction implementation performed by employing the SLM scheme between the quadrate amplitude modulation (QAM) mapping and bandwidth-subdivision operations at the transmitter side, successful PAPR reduction results were achieved in a straightforward and effective manner. In the simulations, the effect of the related way of SLM application on alleviating the PAPR and spectral leakages of the UFMC signal amplified via the solid state power amplifier (SSPA) was investigated for various number of phase factor combinations. Besides, the impact of SLM on the bit error rate (BER) of the UFMC waveform was analyzed for varied values of SSPA parameters called smoothness (p) and input back off (IBO) controlling the linearity and operation point of the SSPA, respectively.

An efficient SLM technique based on migrating birds optimization algorithm with cyclic bit flipping mechanism for PAPR reduction in UFMC waveform

The peak-to-average power ratio (PAPR) is one of the most serious issues to be dwelled on, carefully, in wireless communication. It is not possible to take the advantage of multicarrier transmission strategy without handling the problem of high PAPR arising from the usage of multiple subcarriers for generating the time domain transmission signals. As being a kind of multicarrier waveform, universal filtered multicarrier (UFMC) which is developed a short time ago as a contender waveform for the fifth generation (5G) telecommunication systems, suffers from the high PAPR values of its transmission signals as well. By considering the related issue, we developed a new selective mapping (SLM) technique based on migrating birds optimization (MBO) algorithm to offer an efficient solution to the problem of high PAPR in the UFMC waveform. In the proposed MBO-based SLM (MBO–SLM) scheme, in order to perform an effective phase optimization in discrete space, cyclic bit flipping mechanism is integrated to the MBO algorithm. According to the simulation results, with our proposed MBO–SLM technique, significant improvement is achieved in the PAPR reduction performance of the conventional SLM method thanks to the MBO-based phase optimization process supported by the cyclic bit flipping mechanism.

A novel discrete cuckoo search algorithm‐based selective mapping technique to minimize the peak‐to‐average power ratio of universal filtered multicarrier signal

SummaryThe universal filtered multicarrier (UFMC), which has emerged as a product of the intensive studies carried out for developing alternative waveforms compatible with the oncoming fifth generation (5G) technology, has rapidly become one of the few waveforms considered seriously to be utilized in the next generation telecommunication systems due to its exclusive features. However, high peak‐to‐average power ratio (PAPR) problem specific to the multicarrier waveforms is waiting for researchers as the primary issue to be tackled in the UFMC waveform. To address this issue, an efficient PAPR reduction scheme called discrete cuckoo search algorithm‐based selective mapping (DCS‐SLM) is suggested in this paper. While creating the proposed DCS‐SLM scheme, in order to make the original CS algorithm suitable to be integrated into the conventional SLM method, a novel DCS algorithm was developed. Thanks to the related DCS algorithm, it becomes possible in the SLM technique to perform phase sequence optimization, which is a combinatorial optimization process that can be carried out in discrete space. It is clearly observed from the simulation results that the integration of our novel DCS algorithm to create a new PAPR reduction technique called DCS‐SLM leads to a remarkable performance improvement in the conventional SLM method due to the DCS‐based phase optimization through which the PAPR of UFMC signals are reduced to minimum levels.

Performance analysis of UFMC waveform in graded index fiber for 5G communications and beyond

For the first time, we demonstrate in this paper an intensity-modulation direct-detection (IMDD) universal filtered multi-carrier (UFMC) system through several hundred meters of multimode fiber (MMF) that can be adopted for 5G communications and beyond. The proposed system is simulated and evaluated in terms of bit error rate (BER), Q factor, out of band (OOB) emission and Peak-to-Average Power Ratio (PAPR), at a data rate of 10 Gb/s. It is shown that filtering used with UFMC reduces the OOB radiation by 40 dB compared to orthogonal frequency division multiplexing (OFDM). Moreover, we prove that UFMC gives lower values of BER than OFDM, and even if the PAPR ratio of UFMC is higher than OFDM, the gap remains small. The results also show that using a Volterra equalizer with increasing taps enables to obtain acceptable performance through the MMF in terms of BER, even with high number of excited mode groups.

Performance Analysis of the Universal Filtered Multi-Carrier (UFMC) Waveform for 5G System

In the 5th generation mobile communication (5G) system, it is required to provide three different types of services, including enhanced Mobile Broadband (eMBB), massive machine-type communication (mMTC), and ultra-reliable and low-latency communication (URLLC).To meet all those demand in 5G, the waveform is crucial. Although the CP-OFDM waveform has been wildly used in 4G, it is hardly to satisfy the requirements of 5G.A lot of candidate waveforms are discussed for 5G system, including UFMC, FBMC, F-OFDM etc. In this paper, the UFMC waveform is discussed, the different filters and different frequency width of the subband in UFMC system are studied and appropriate parameters for the system are recommended.

Hardware Complexity Reduction in Universal Filtered Multicarrier Transmitter Implementation

The inclusion of machine-type communication in the 5G technology has motivated the research community to explore new derivative waveforms of orthogonal frequency division multiplexing. Filter bank multicarrier, universal filtered multicarrier (UFMC), and generalized frequency division multiplexing techniques are under evaluation with respect to their suitability to 5G requirements. In addition to acceptable spectral performance, investigation on computational complexity reduction while addressing flexibility can help in the selection of suitable waveform among multiple options available for 5G. In this regard, based on analysis of computation involved in UFMC waveform construction, few reduced complexity solution for UFMC transmitter implementations are recently proposed. However, hardware-implementation-related issues have not been discussed in detail. In this paper, we have proposed reduced complexity hardware solutions for all three constituent blocks, i.e., inverse discrete Fourier transform (IDFT), finite impulse response (FIR) filter, and spectrum shifting blocks of a UFMC transmitter. For IDFT part, a reduced complexity IFFT solution using Radix-2 decimation in a time technique is presented, where more than 42% computations can be avoided. It is also shown that how five times less number of multipliers can be used in an FIR filter to simplify filter architecture. Finally, a highly efficient method is presented to compute spectrum shifting coefficients through small sized lookup table.