Xiaojun Chen^*, Yunxiao Zu

Journal of Information Hiding and Privacy Protection, Vol.3, No.3, pp. 101-107, 2021, DOI:10.32604/jihpp.2021.025225

Abstract This paper focuses on the forward error correction (FEC), the basic parameters determination of the RS convolution code, Turbo code and the LDPC code, and the corresponding encoding and decoding algorithm in power line communication (PLC) standard. Simulation experiment which is designed for narrow-band power line communication system based on OFDM is done. The coding using RS convolution code, Turbo code and LDPC code are compared, and further it is determined that which encoding method is more suitable for power line communication in China. More >

Arun Kumar¹, Sumit Chakravarty², S. Suganya³, Mehedi Masud^4,*, Sultan Aljahdali⁴

Computer Systems Science and Engineering, Vol.42, No.2, pp. 483-492, 2022, DOI:10.32604/csse.2022.022899

Abstract 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… More >

Ahmed Hammoodi¹, Lukman Audah¹ , Laith Al-Jobouri^2,*, Mazin Abed Mohammed³, Mustafa S. Aljumaily⁴

CMC-Computers, Materials & Continua, Vol.71, No.2, pp. 2721-2738, 2022, DOI:10.32604/cmc.2022.020091

Abstract OFDM based waveforms are considered as the main part of the latest cellular communications standard (namely 5G). Many inherited problems from the OFDM-Based LTE are still under investigation. Getting rid of the out of band emissions is one of these problems. Ensuring low out of band emission (OOBE) is deemed as one of the most critical challenges to support development of future technologies such as 6G and beyond. Universal Filtered Multi Carrier (UFMC) has been considered as one of the candidate waveforms for the 5G communications due to its robustness against Inter Carrier Interference (ICI) and the Inter Symbol Interference… More >

Hend Ibrahim¹, Abeer D. Algarni^2,*, Mahmoud Abdalla¹, Walid El-Shafai^3,4, Fathi E. Abd El-Samie^2,3, Naglaa F. Soliman^1,2

CMC-Computers, Materials & Continua, Vol.71, No.2, pp. 3293-3318, 2022, DOI:10.32604/cmc.2022.022436

Abstract Optical Wireless Communication (OWC) is a new trend in communication systems to achieve large bandwidth, high bit rate, high security, fast deployment, and low cost. The basic idea of the OWC is to transmit data on unguided media with light. This system requires multi-carrier modulation such as Orthogonal Frequency Division Multiplexing (OFDM). This paper studies optical OFDM performance based on Intensity Modulation with Direct Detection (IM/DD) system. This system requires a non-negativity constraint. The paper presents a framework for wireless optical OFDM system that comprises (IM/DD) with different forms, Direct Current biased Optical OFDM (DCO-OFDM), Asymmetrically Clipped Optical OFDM (ACO-OFDM),… More >

N. Manikanda Devarajan^1,*, S. Thenmozhi², K. Jayaram³, R. Saravanakumar⁴

Intelligent Automation & Soft Computing, Vol.32, No.2, pp. 1167-1178, 2022, DOI:10.32604/iasc.2022.021558

Abstract Orthogonal Frequency Division Multiplexing (OFDM) is a wireless communication technology that is used for highly reliable and high data rate communication. In a multi-user OFDM system, the interference has occurred in the receiver side between the consecutive OFDM symbols. This interference reduces the performance of the OFDM system. To achieve good quality in received symbols the interference level should be minimized. The conventional cancellation system requires higher interference reduction time and power. These limitations of the conventional interference cancellation architectures for OFDM systems are overcome by proposing efficient and low power interference cancellation architecture. Hence, this paper proposes a novel… More >

I. Kalphana^1,*, T. Kesavamurthy²

Computer Systems Science and Engineering, Vol.41, No.1, pp. 171-185, 2022, DOI:10.32604/csse.2022.019799

Abstract Higher transmission rate is one of the technological features of prominently used wireless communication namely Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing (MIMO–OFDM). One among an effective solution for channel estimation in wireless communication system, specifically in different environments is Deep Learning (DL) method. This research greatly utilizes channel estimator on the basis of Convolutional Neural Network Auto Encoder (CNNAE) classifier for MIMO-OFDM systems. A CNNAE classifier is one among Deep Learning (DL) algorithm, in which video signal is fed as input by allotting significant learnable weights and biases in various aspects/objects for video signal and capable of differentiating from… More >

Jae-Hyun Ro¹, Jong-Gyu Ha², Woon-Sang Lee², Young-Hwan You³, Hyoung-Kyu Song^2,*

CMC-Computers, Materials & Continua, Vol.70, No.2, pp. 3625-3636, 2022, DOI:10.32604/cmc.2022.020596

Abstract This paper proposes the multiple-input multiple-output (MIMO) detection scheme by using the deep neural network (DNN) based ensemble machine learning for higher error performance in wireless communication systems. For the MIMO detection based on the ensemble machine learning, all learning models for the DNN are generated in offline and the detection is performed in online by using already learned models. In the offline learning, the received signals and channel coefficients are set to input data, and the labels which correspond to transmit symbols are set to output data. In the online learning, the perfectly learned models are used for signal… More >

Amit Kumar¹, Adesh Kumar^2,*, Geetam Singh Tomar³

Computer Systems Science and Engineering, Vol.40, No.2, pp. 645-659, 2022, DOI:10.32604/csse.2022.019449

Abstract The fourth-generation (4G) and fifth-generation (5G) wireless communication systems use the orthogonal frequency division multiplexing (OFDM) modulation techniques and subcarrier allocations. The OFDM modulator and demodulator have inverse fast Fourier transform (IFFT) and fast Fourier transform (FFT) respectively. The biggest challenge in IFFT/FFT processor is the computation of imaginary and real values. CORDIC has been proved one of the best rotation algorithms for logarithmic, trigonometric, and complex calculations. The proposed work focuses on the OFDM transceiver hardware chip implementation, in which 8-point to 1024-point IFFT and FFT are used to compute the operations in transmitter and receiver respectively. The coordinate… More >

A. Jayamathi¹, T. Jayasankar^2,*

Intelligent Automation & Soft Computing, Vol.31, No.1, pp. 311-324, 2022, DOI:10.32604/iasc.2022.019473

Abstract Orthogonal frequency division multiplexing is one of the efficient and flexible modulation techniques, and which is considered as the central part of many wired and wireless standards. Orthogonal frequency division multiplexing (OFDM) and multiple-input multiple-output (MIMO) achieves maximum spectral efficiency and data rates for wireless mobile communication systems. Though it offers better quality of services, high peak-to-average power ratio (PAPR) is the major issue that needs to be resolved in the MIMO-OFDM system. Earlier studies have addressed the high PAPR of OFDM system using clipping, coding, selected mapping, tone injection, peak windowing, etc. Recently, deep learning (DL) models have exhibited… More >

Arun Kumar^1,*, Sivabalan Ambigapathy², Mehedi Masud³, Emad Sami Jaha⁴, Sumit Chakravarty⁵, Kanchan Sengar¹

CMC-Computers, Materials & Continua, Vol.69, No.3, pp. 2967-2981, 2021, DOI:10.32604/cmc.2021.019092

Abstract The article introduces Non-Orthogonal Multiple Access (NOMA) and Filter Bank Multicarrier (FBMC), known as hybrid waveform (NOMA-FBMC), as two of the most deserving contenders for fifth-generation (5G) network. High spectrum access and clampdown of spectrum outflow are unique characteristics of hybrid NOMA-FBMC. We compare the spectral efficiency of Orthogonal Frequency Division Multiplexing (OFDM), FBMC, NOMA, and NOMA-FBMC. It is seen that the hybrid waveform outperforms the existing waveforms. Peak to Average Power Ratio (PAPR) is regarded as a significant issue in multicarrier waveforms. The combination of Selective Mapping-Partial Transmit Sequence (SLM-PTS) is an effective way to minimize large peak power… More >