Universal Filtered Multicarrier Research Articles

Comparison of different New Radio (NR) waveforms for wireless communications.

New Radio (NR) waveforms of existing wireless communication systems need further improvement in order to support future wireless communications. NR is the radio interface technology proposed by the 3rd Generation Partnership Project (3GPP) for 5G. Prototype Filter (PF) of NR plays a vital role in performance improvement of wireless systems. NR waveforms can adapt in a better way to different channel conditions. Some of the NR filtering techniques are Filtered-OFDM (F-OFDM), Filter Bank Multi-Carrier (FBMC), and Universal Filtered Multi-Carrier (UFMC). NR waveforms require performance improvement when high reliability, massive connectivity, lower power consumption, and time-critical applications are required. Areas of improvement are Power Spectral Density (PSD), Bit Error Rate (BER), Signal to Interference Ratio (SIR), Doppler Diversity, and Peak to Average Power Ratio (PAPR). This paper compares different performance parameters of Filtered-OFDM, FBMC, and UFMC using existing proto-type filters and novel proto-type filters. The novel and better PFs, described in the paper, were proposed first time by the authors and his research group. Proposed novel prototype filters for FBMC, Filtered-OFDM, and UFMC are respectively Binomial filter and Fractional Powered Binomial Filter (FPBF). With FPBF based OFDM, PSD improvement was 97.5 dB, and BER improvement was 0.07 at 0 dB SNR. With Binomial filter based FBMC, OOBE improvement was 19.7 dB and BER improvement was 0.03 at 0 dB SNR. PAPR improvement with Binomial filter based FBMC was 1.16 dB at 64-QAM and 1.1 dB at 256-QAM. With FPBF based UFMC, improvement of interference level was 122 dB within 3rd~52th sub-bands due to 1st sub-band. BER improvement was 0.09 at 0 dB SNR. SIR improvement was 5. 27 dB with 15 KHz sub-carrier spacing and 16.55 dB with 30 KHz sub-carrier spacing of UFMC. Novel NR filters, discussed in the paper, are good candidates for future 6G wireless systems.

An analysis of 5G-MIMO communication system based SS for centralized cooperative and non-cooperative users

The purpose of 5G-MIMO communication systems is to boost the intensity of the received signal, and facilitate the application of the users’ apparatus. However, in band-grabbing systems such as these, the accessibility of a spectrum is hindered by gridlocks. Also, to be considered is the spectrum’s waveform, which is the type that contends with 5G networks specifically. This undertaking involves the development of a 5G-MIMO communication system based SS, in which the spectrum is enhanced, by way of a spectrum sensing (SS) algorithm. By replicating the energy detection procedure, this recommended SS algorithm engages the cosine law to filter the traffic signal, and subsequently portions it using the Welch algorithm. The Hann algorithm is then utilized, to window the traffic signal, to damp the high power delivered to the MIMO. The key role, of the SS algorithm, is to sense a spectrum for 5G-MIMO communication system, with the capacity to damp the MIMO effect for a variety of waveforms. The SS algorithm expressions are applicable for both non-cooperative and centralized cooperative users. For each expression, an examination was performed for waveforms used by 5G-MIMO communication systems. This included filtered-orthogonal frequency division multiplexing (F-OFDM), universal filtered multi-carrier (UFMC), and filter bank multi-carrier (FBMC) waveforms. The operating parameters, including SNR, the signal span and power, the antenna count, as well as the types of modulation for both non-cooperative and centralized cooperative users, were scrutinized. The simulation results revealed a notable achievement for the parameters lower than zero dB of SNR, greater than 95% global detection probability, less than 1% global system error probability, and less than 1% global false alarm probability. An evaluation of the recommended system’s parameters discloses its superiority, in comparison to other previously developed systems.

Performance Optimization of Universal Filtered Multicarrier Technique for Next Generation Communication Systems

Next generation communication systems require better performance to support high - bandwidth, peak data rate, spectral efficiency, mobility, connection density, positioning accuracy, etc. Investigation on efficient modulation technique for next generation has become very important so as to meet its expectations. In this paper performance optimization of universal filtered multicarrier (UFMC) technique for next generation communication systems have been investigated. Dolph-Chebyshev (DC) and Kaiser-Bessel- derived (KBD) filters have been used to optimize power spectral density, channel equalization, bit error rate, and peak to average power ratio (PAPR). It has been observed that KBD filter response is comparatively better than DC filter. Effect of filter length also influences the system performance, filter with bigger length improves performance at the cost of computational complexity. Performance of UFMC has been compared with that of orthogonal frequency division multiplexing (OFDM) technique. The present work of investigations on UFMC that is based on subband filtering is our original research work that has been carried out for its suitability for next generation communication systems. It has simple design structure, lower computational complexities and better performance in terms of BER compared to OFDM and f-ODFM systems. It has comparatively low PAPR than GFDM and FBMC techniques.

Study and Comparative Analysis of OFDM and UFMC Modulation Schemes

In various areas, wireless systems are used. In order to allocate the available time and frequency resources, these wireless systems require flexible mechanisms. With 5G, transmission rates will be higher, latency will be lower and quality of service and channel capacity will be higher. The physical layer must be able to generate flexible waveforms to meet the above requirements. Currently, Orthogonal Frequency Division Multiplexing (OFDM) transmission does not support 5G communication. In the case of 4G/OFDM, there are many problems in terms of out of band emission, spectral efficiency, and peak to average power ratio (PAPR). An alternative transmission scheme Universal Filtered Multicarrier (UFMC) is introduced to address this problem. The paper compares OFDM with UFMC. The purpose of this paper is to discuss Spectral Density, Spectral Efficiency, Signal to Noise Ratio (SNR) and Bit Error Rate (BER). In comparison to OFDM, UFMC provides better performance.

The impact of M-ary rates on various quadrature amplitude modulation detection

The 5G system-based cognitive radio network is promised to meet the requirements of huge data applications with spectrum. However, the M-ary effect on the detection has not been thoroughly investigated. In this paper, an M-ary of quadrature amplitude modulation detection system is studied. Many rates are used in this study 4, 16, 64, and 256 constellation points. The detection system is applied to cooperative spectrum sensing to enhance the performance of detection for various rates of M-ary with low signal-to-noise ratio (SNR). Further, three kinds of signals based 5G system are sensed: filtered-orthogonal frequency division multiplexing (F-OFDM), filter bank multi-carrier (FBMC), and universal filtered multi-carrier (UFMC). The best detection performance is obtained when the M-ary=4 and number of SUs=50 user, whereas the worst detection performance is obtained when the M-ary=256 and number of SUs=10 user, as revealed in the simulation results. In addition, the detection performance for the F-OFDM signal is better than that of UFMC and FBMC signals for SNR <0 dB.

Study and Analysis of UFMC Technology in 5G Communications

Wireless communication technology plays a significant role in the development of mobile technology. Every user requires their own spectrum. However, spectrum bands are limited. Therefore, the communication system must be efficient. This paper discusses the Universal Filtered Multi-Carrier (UFMC) technology, a new promising technology intended to improve mobile networks in the future. This technology is less susceptible to estimate errors of time shifts and frequency shifts. 5G’s major goals are speed, low latency, Quality of Service, and channel capacity. Physical layer waveform generation must be flexible in order to meet these requirements. Currently, 4G-LTE transmissions are not compatible with 5G technologies because of Out of Band radiation and high Peak to Average Power Ratio (PAPR). A future cellular network could benefit from UFMC. The performance of UFMC is evaluated using Power Spectral Density, PAPR, Signal-to-Noise Ratio, and Bit Error Ratio for 5G wireless communications. It is possible that UFMC will be more efficient and gives better solution.

BER and PSD Improvement of FBMC with Higher Order QAM Using Hermite Filter for 5G Wireless Communication and beyond

Nowadays, multicarrier modulation schemes are being widely used in wireless communication system than single-carrier modulation techniques. Single-carrier modulation schemes are less capable of dealing with multipath fading channels than multicarrier modulation schemes, which results in lower spectral efficiency. Multicarrier modulation schemes have the ability to overcome multipath fading channels. Multicarrier modulation technique currently used in 4G technology in many countries is OFDM and it is easy for implementation, immune to interference, and provide fast data rate. However, the rising users demand on wireless communication resulted in need for further advancement of wireless communication system. The present OFDM transmission does not fulfill the requirements of 5G wireless communication system and beyond due to major limitations such as out of band emission and usage of cyclic prefix. To overcome the challenges of OFDM, different modulation schemes like Filter Bank Multicarrier with Offset-QAM, Filter Bank Multicarrier with QAM, Universal Filter Multicarrier, Filtered-OFDM, and Weighted Overlap and Added-OFDM are proposed. In this study, the Filter Bank Multicarrier with QAM using Hermite prototype filter is proposed to overcome drawbacks of OFDM and all other proposed waveforms. The performances of each multicarrier technique are analyzed based on power spectral density and bit error rate. Simulation result shows that the power spectral density of FBMC with QAM using Hermite filter resulted in 4.7 dB reduction of out of band emission compared to FBMC with QAM using PHYDYAS filter. The bit error rate is also reduced for Vehicular A, Vehicular B, Pedestrian A, and Pedestrian B channel models.

Selective Mapping Scheme for Universal Filtered Multicarrier

The next step in mobile communication technology, known as 5G, is set to go live in a number of countries in the near future. New wireless applications have high data rates and mobility requirements, which have posed a challenge to mobile communication technology researchers and designers. 5G systems could benefit from the Universal Filtered Multicarrier (UFMC). UFMC is an alternate waveform to orthogonal frequency-division multiplexing (OFDM), in filtering process is performed for a sub-band of subcarriers rather than the entire band of subcarriers Inter Carrier Interference (ICI) between neighbouring users is reduced via the sub-band filtering process, which reduces out-of-band emissions. However, the UFMC system has a high Peak-to-Average Power Ratio (PAPR), which limits its capabilities. Metaheuristic optimization based Selective mapping (SLM) is used in this paper to optimise the UFMC-PAPR. Based on the cognitive behaviour of crows, the research study suggests an innovative metaheuristic optimization known as Crow Search Algorithm (CSA) for SLM optimization. Compared to the standard UFMC, SLM-UFMC system, and SLM-UFMC with conventional metaheuristic optimization techniques, the suggested technique significantly reduces PAPR. For the UFMC system, the suggested approach has a very low Bit Error Rate (BER).

A NOVEL SCHEME UFMC-DSNT FOR PAPR REDUCTION IN 5G SYSTEMS

The universal filtered multi-carriers (UFMC) waveform is a powerful candidate for multi-carrier modulation (MCM) that is employed in 5G systems. This is thanks to its low bit error rate (BER) and low latency compared to other waveforms, such as generalized frequency division multiplexing (GFDM). The high peak-to-average power ratio (PAPR) is one of the main challenges found in all MCM systems. As the output signal of the UFMC has large peaks, some distortions occur in the signal due to overshoot of the linear region of the high-power amplifier (HAP), which dramatically degrades the BER. Accordingly, it is known from several previous research studies that most proposals to reduce PAPR for the UFMC system have been difficult to implement or have required sending information in parallel to the receiver. For this reason, this paper proposes a new alternative, which is easily implemented and does not require the transmission of secondary information for PAPR reduction. This is done by applying the discrete sliding norm transform (DSNT) technique on the UFMC system, highlighting the proposed DSNT-UFMC scheme. As this previous scheme has not been addressed in any previous research work, it presents, the key contribution of this paper. The simulation results show that the proposed scheme outperforms the conventional one in terms of PAPR reduction, whose improvement reaches 94.6% using the proposed scheme.

A Comprehensive Survey of Candidate Waveforms for 5G, beyond 5G and 6G Wireless Communication Systems

The evolution of global mobile data over the past decades in broadcasting, Internet of Things (IoT), education, healthcare, commerce, and energy has put strong pressure on 3G/4G mobile networks to improve their service offerings. These generations of mobile networks were initially invented to meet the requirements of the above-mentioned applications. However, as the requirements in these applications continue to increase, new mobile technologies such as 5G (fifth generation), 5G and beyond (B5G, beyond fifth generation), and 6G (sixth generation) are still progressing and being experimented. These networks are very heterogeneous generations of mobile networks that will have to offer very high throughput per user, good energy efficiency, better traffic capacity per area, improved spectral efficiency, very low latency, and high mobility. To meet these requirements, the radio interface of future mobile networks will have to be flexible and rationalized the available frequency resources. Therefore, new modulation methods, access techniques and waveforms capable of supporting these technological changes are proposed. This review presents brief descriptions of the types of 5G, B5G, and 6G waveforms. The 5G consists of OFDM including its transmission techniques: generalized frequency division multiplexing (GFDM), filter bank based multi-carrier (FBMC), universal filtered multi-carrier (UFMC), and index modulation (IM). Meanwhile, the 6G covers orthogonal time frequency space (OTFS), orthogonal chirp division multiplexing (OCDM) and orthogonal time sequence multiplexing (OTSM). The networks’ potentialities, advantages, disadvantages, and future directions are outlined.

An analysis of low complexity of 5G-MIMO communication system based CR using hybrid filter detection

The exponential growth in wireless communication has resulted in a high demand for novel wireless services within the frequency bands that can deal with the challenge pertaining to the current spectrum shortage. Thus, a 5G-MIMO based CR communication system has been developed to enhance the spectrum by employing a spectrum sensing (SS) algorithm. This recommended SS algorithm, based on the hybrid filter detection (HFD) method, employs the Cosine law for filtering the traffic signal, and then enables segmentation by applying the Welch algorithm. Then, the Hann algorithm is employed to window the traffic signal, and facilitates damping the MIMO impact for different waveforms. This also includes universal filtered multi-carrier (UFMC), filtered-orthogonal frequency division multiplexing (F-OFDM), filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA), and Generalized Frequency Division Multiplexing (GFDM) waveforms. Also, evaluation of the operating parameters such as SNR, the antenna count, the signal span, and power as well as computational complexity was done. Based on the simulation results, a notable achievement was seen for the parameters that were below 0 dB of SNR, <0.09 % global system error probability, >96 % global detection probability, <0.06 % global false alarm probability, and possessing simple complexity. The recommended system’s parameters were assessed, which demonstrated its superiority versus other previously developed systems. This algorithm was found to identify all types of 5G signals and not just one type of 5G.

Analysis of Multi Carrier Modulation techniques for 5G Physical Layer Communications

The more enchanting Multicarrier Communication (MCM) techniques like Fifth Generation (5G), Long Term Evolution (LTE) and Fourth Generation (4G) are the enhancing techniques that contribute the progress of wireless communication systems. The most effective way to save resources in 5G is to make efficient use of all existing discontinuous spectrums, which maximizes Spectrum Efficiency (SE). A valid comparison of many 5G MCM techniques is made in this work, namely Universal Filter Multi Carrier (UFMC), Filter Bank Multi Carrier (FBMC) and Orthogonal Frequency Division Modulation (OFDM). Various Key Performance Indicators (KPI) such as Bit Error Ratio (BER), Signal to Interference Ratio (SIR), Power Spectral Density (PSD) and ratio between Peak Power and Average Power, Throughput, and Spectral Efficiency (SE) are evaluated and compared under various realistic channels. UFMC Modulation technique is compatible with existing channel estimation and detection techniques and further improves SE. The SE of FBMC has been improved by 2% with Hermite filter when compared to PHYSDAS, RRC prototype filters. It has been observed that FBMC offered better SIR, Throughput, also a complex design of filter reduced BER and PAPR.

Deep bidirectional LSTM for the signal detection of universal filtered multicarrier systems

Universal filtered multicarrier (UFMC) has emerged as a potential waveform contender of orthogonal frequency division multiplexing (OFDM) for the fifth generation (5G) and beyond wireless systems. In this paper, we propose a bidirectional long short-term memory (Bi-LSTM)-based detector for the UFMC system. The proposed detector directly detects the transmitted symbols using the deep learning (DL)-based training data. The system is first trained with the aid of training data and pilot symbols. The training tunes the DL-based network parameters. During the testing phase, the signal is detected using the trained network. The performance of the proposed scheme is compared with that of the DL-aided OFDM system, and with the signal detection strategies using the conventional channel estimation techniques. Our simulations show that the proposed Bi-LSTM-based DL can flexibly and effectively detect UFMC signals.

Multicarrier Modulation Schemes for 5G Wireless Access

The 5G wireless access technology will supersede its predecessor, 4G, in the current decade, at first coexisting with it and later as a standalone technology. This work examines and compares the performance of the following orthogonal multicarrier schemes: Cyclic Prefix Orthogonal Frequency Division Multiplexing (CP-OFDM), Windowed Orthogonal Frequency Division Multiplexing (W-OFDM), Filtered Orthogonal Frequency Division Multiplexing (F-OFDM), Universal Filtered Multi-Carrier (UFMC), and Filter Bank Multi-Carrier (FBMC). The system architecture of each scheme is investigated while considering the performance in fading channel models. The simulation was performed using a standard set of parameters, and the performance was appraised based on Power Spectral Density (PSD), Peak to Average Power Ratio (PAPR), Complementary Cumulative Distribution Function (CCDF) of PAPR, Bit Error Rate (BER), and Signal to Noise Ratio (SNR). In addition, a comprehensive analysis is presented concerning filter or window implementation, filtering method, orthogonality, roll-off rate, spectral leakage, spectral efficiency, computational complexity, and runtime complexity. Based on the results, each scheme has its advantages and disadvantages compared with the other methods. FBMC, F-OFDM, and W-OFDM are preferred for better spectrum utilization, transmission accuracy, and power efficiency, respectively. UFMC offers a fine balance between these multicarrier schemes. Therefore, the modulation scheme for the future physical layer will strongly depend on the requirements.

Performance evaluation of hybrid transform for universal filtered multi‐carrier system

AbstractHigh peak to average power ratio (PAPR) is viewed as a serious limitation of all multi‐carrier systems. In this article, a companding transform with clipping technique is proposed for universal filtered multi‐carrier (UFMC) system. The proposed companding transform successfully reduces the PAPR by expanding the small amplitude signals and compressing the peak amplitude signals. Moreover, the combination of companding and clipping further reduces the PAPR. Besides, the proposed scheme provides more flexibility by properly selecting companding parameters and clipping ratio (CR). Additionally, this article presents the performance evaluation of various nonlinear companding transforms (NCTs) of the UFMC system in terms of PAPR reduction, bit‐error‐rate, and reduced out‐of‐band emissions. Simulation results confirm that the proposed hybrid transform provides superior system performance when compared to other NCTs. The proposed hybrid transform with CR of 1.4 provides superior PAPR diminution of 8.5 dB and net gain of 8.9 dB when compared to other schemes. Finally, the proposed hybrid transform is validated by using wireless‐open access‐research platform over real time channel.

Maximal-Minimum hybrid approach with decomposed SLM technique for 5G UFMC system PAPR reduction

The Universal Filtered Multi-carrier (UFMC) system's low latency, minimal out-of-band, and low frequency offset support high spectral efficiency and impact 5 G cellular networks. Due to its high peak-to-average power ratio (PAPR), the system's performance is severely degraded. This paper proposes a hybrid Maximal-Minimum approach with decomposed selective mapping to minimize PAPR constraints for 5 G UFMC systems. The complex signal is decomposed into real and imaginary branches, allowing the inverse fast Fourier transform (IFFT) operation. In each branch, different phase vectors are mixed with real and imaginary terms. The FIR response is based on individually optimized PAPR values, which are then copied for transmission. Simulations showed that the proposed method reduced PAPR by optimizing the weighting factor within the Out of Band (OoB) range. It is superior in Bit Error rate (BER)-wise, reduction as compared with selective mapping (SLM) and decomposed-UFMC-SLM.

Performance analysis of modulation techniques in 5G communication system

In the 5 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup> generation mobile communication (5G) system, better bitrate, better power consumption, and better Bit Error Rate are needed. To meet all these requirements in 5G, the waveform is important. Although the Orthogonal Frequency Division Multiplexing (OFDM) modulation scheme has been commonly used in 4G, it is difficult to meet the requirements of 5G. A lot of candidate waveforms are discussed in the 5G system included Filter Bank Multicarrier (FBMC), Universal Filtered Multicarrier (UFMC), Filtered OFDM (F-OFDM), and Generalized Frequency Division Multiplexing (GFDM), etc. However, since GFDM is no longer widely used, in this paper, FBMC, UFMC, and F-OFDM modulation schemes are discussed and compared with OFDM. Power Spectral Density (PSD), Bit Error Rate (BER), Transmitted Signal Power, Peak Average Power Ratio (PAPR) and Bit Rate parameters of the modulation schemes are studied and compared with OFDM. FBMC demonstrates to be the most promising modulation scheme for 5G systems.

F-OFDM in a novel form for analyzing 5G networks

The need for internet of things (IoT) and machine-to-machine communication (MTC) has been growing rapidly all across the world. To meet the client's needs, many literature reviews were undertaken in several countries. Orthogonal frequency division multiplexing (OFDM), Universal Filtered Multi-Carrier (UFMC), filter-bank multicarrier offset construction amplitude modulation (FBMC-OQAM), generalized frequency division multiplexing (GFDM), and others are candidates for LTE, LTE advance, and 5G, according to the majority of the researchers. However, because it is sensitive to propagation and noise, such as amplitude, with a huge dynamic range, it requires RF power amplifiers with a high peak to average power quantitative relationship; consequently, it is not recommended for LTE, LTE advance, or 5G. As a result, the same concerns were addressed by introducing innovative type filtered orthogonal frequency division multiplexing (F- OFDM), which was the subject of this study. In addition, F-OFDM mathematical models were constructed and simulated in the MATLAB software environment. To validate the proposed innovative F-OFDM, OFDM was compared. For innovative F-OFDM, the simulated result was 0.00083333 bit error rate (BER). Furthermore, the bit error rate (BER) of F-OFDM over OFDM was 89.4 percent, and the peak to average power ratio was 17 percent. The simulation results unmistakably show that the suggested innovative F-OFDM is the greatest fit for LTE, LTE advanced, and 5G contenders.

Research of the Influence of the Quadrature Components Mismatch on the Noise Immunity of OFDM and UFMC Signals

The method of direct modulation using complex signals is used to implement signal paths of transmitters in base stations of cellular communication systems. In the process of modulation, there are mismatches of the gain coefficient and the phase of the quadrature components of the signal. Mismatch degrades the Error Vector Magnitude (EVM) at the receiver, which in turn results in an increased Bit Error Rate (BER). The quality of the received signal is expressed in bit error rate. The mismatch of the amplitude and phase of the quadrature components is one of the most important factors making the greatest contribution to the amplitude of the error vector, and which must be investigated. The paper presents a research of the influence of the mismatch on the OFDM (Orthogonal frequency-division multiplexing) and UFMC (universal filtered multi-carrier) technologies. A model of the transmitter, communication channel and receiver for OFDM and UFMC signals has been developed. The model was built in the MatLab software environment. In the work, by studying the simulation model, the dependence of the noise immunity of technologies was studied by changing the parameters of the communication channel, such as the amplitude and phase mismatch of the quadrature components of the signal, as well as the signal-to-noise ratio. Also, a comparative analysis of such signal parameters as the occupied bandwidth, peak to average ratio, frequency of occurrence of bits with an error was carried out. Based on the results of the study, graphs of the dependence of the error probability and the signal peak to average ratio on the mismatch of the quadrature components were obtained for two technologies, OFDM and UFMC. The study allows us to highlight the advantages of UFMC technology, which are expressed in spectral efficiency, noise immunity and the level of the signal peak to the average ratio.

Digital filtering based on fast theoretical and numerical transformations for 5G systems

Currently, a trend to increase the performance of wireless data transmission systems can be observed. This requires a new protocol for mobile communications. The draft IMT-2020 standard involves the use of promising 5G mobile networks. These systems must have characteristics that will exceed 4G standards. New technologies will provide a higher data rate and minimal network delays, which should not exceed 1 ms. To achieve these goals, the 5G standard involves the broadband transmission using FBMC (Filter Bank MultiCarrier) or UFMC (Universal Filtered MultiCarrier). Studies have shown that the UFMC method allows for better subcarrier filtration compared to FBMC comb filtration. However, the use of this method requires high computational costs, which negatively affects the speed of information transfer and network delays. Therefore, the aim of the article is to reduce network delays when using the technology of filtering UFMC signals by using a fast algorithm for performing theoretical and numerical transformations (TNT). Therefore, the development of a fast algorithm for performing theoretical and numerical signal transformations for OFDM systems that support the 5G standard is an urgent task