A Wavelet-Based Approach with NLMS Equalization and Fading Channel Compensation for Improved Spectral Efficiency and Error Rate
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Abstract
Within the realm of communication, Orthogonal Frequency Division Multiplexing (OFDM) has emerged as a highly effective and commendable approach. The fundamental structure of Orthogonal Frequency Division Multiplexing (OFDM) encompasses the utilization of Fast Fourier Transform (FFT) to efficiently compute the Discrete Fourier Transform (DFT) of a given source signal through expedited computational processes. Nevertheless, the Orthogonal Frequency Division Multiplexing (OFDM) system utilizing Fast Fourier Transform (FFT) encounters various limitations, such as inadequate localization, increased error rates at high data rates, and limited spectrum efficiency. In order to tackle these issues, the utilization of wavelet-based orthogonal frequency division multiplexing (OFDM) emerged as an alternative to substitute the fast Fourier transform (FFT) with the discrete wavelet transform (DWT). In this study, we have designed an upgraded discrete wavelet transform-orthogonal frequency division multiplexing (DWT-OFDM) system using normalized least mean squares (NLMS) equalization approach. The objective of this implementation is to minimize the bit error rate (BER) values in comparison to the conventional fast Fourier transform-orthogonal frequency division multiplexing (FFT-OFDM) system. Furthermore, a channel equalization technique is also suggested for fading environments, such as Rayleigh, Rician, and additive white Gaussian noise (AWGN) circumstances. Additionally, the BER comparison also includes various modulation levels, which reveal the effectiveness of the proposed system compared to the typical FFT-OFDM method.
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References
J. A. C. Bingham, “Multicarrier modulation for data transmission: An idea whose time has come”, IEEE Communication Magazines, Vol. 28, No. 5, pp. 5–14, 1990.
P. Gotz, U. Jorn, K. Werner and Z Georg, “A comparison of various MCM schemes”, In: Proc. of 5th International Workshop on OFDM, Hamburg, Germany, pp. 20-1 – 20-5, 2000.
L. Jun, T. T. Thiang, F. Adachi and H. C. Li, “BER performance of OFDM-MDPSK system in frequency selective Rician fading and diversity reception”, IEEE Transactions on Vehicular Technology, Vol. 49, No. 4, pp. 1216-1225, 2000.
D. N. Muhammad, N. Hans and H. Thomas, “On Performance Limits of DFT Spread OFDM Systems”, In: Proc. of IST Mobile and Wireless Communications Summit, Budapest, Hungary, pp., 2007.
T. Hwang, C. Yang, W. Gang, S. Li and G. Y. Li, “OFDM and Its Wireless Applications: A Survey”, IEEE Transactions on Vehicular Technology, Vol. 58, No. 4, pp. 1673-1694, 2009.
R.W. Klein, M.A. Temple, R.A. Raines, and R.L. Claypoole Jr., “Interference Avoidance Communications using Wavelet Domain Transformation Techniques”, IEEE Electronic Letters, Vol. 37, No. 15, pp. 987–989, 2001.
D. Guptha, Vipin B Vats and K. Kamal Garg, “Performance Analysis of DFT-OFDM, DCT- OFDM and DWT-OFDM Systems in AWGN Channel”, In: Proc. of International Conference on Wireless and Mobile Communications, Athens, Greece, pp. 214-216, 2008.
M. B. Veena and M.N.S. Swamy, “Performance analysis of DWT based OFDM over FFT based OFDM and implementing on FPGA”, International Journal of VLSI design & Communication Systems, Vol.2, No. 3, pp. 119-130, 2011.
B. Gupta, G. Gupta, and D. S. Saini, “BER Performance Improvement in OFDM System with ZFE and MMSE Equalizers”, In: Proc. of International Conference on Electronics Computer Technology, Kanyakumari, India, pp. 193-197, April 2011.
A. Kaini, G. Baghersalimi and B. Zanj, “Performance assessment of DFT-OFDM and DWT- OFDM systems in the presence of the HPA Nonlinearity”, In: Proc. of International Conference on Telecommunications, Graz, Austria, pp. 273-278, 2011.
R. Bodhe, S. Narkhede and S. Joshi, “Design of Simulink Model for OFDM and Comparison of FFT-OFDM and DWT-OFDM”, International Journal of Engineering Science and Technology, Vol. 4, No. 5, pp. 1914-1924, 2012.
R. Bodhe, S. Joshi and S. Narkhede, “Performance Comparison of FFT and DWT based OFDM and Selection of Mother Wavelet for OFDM”, International Journal of Computer Science and Information Technologies, Vol. 3, No. 3, pp. 3393-3397, 2012.
A. Deshmukh and S. Bodhe, “Comparison of DCT and Wavelet Based OFDM System Working in 60 GHz Band”, International Journal of Advancements in Technology, Vol. 3, No. 2, pp. 74-83, 2012.
L. Patidar and A. Parikh, “BER Comparison of DCT-based OFDM and FFT-based OFDM using BPSK Modulation over AWGN and Multipath Rayleigh Fading Channel”, International Journal of Computer Applications, Vol. 31, No. 10, pp. 38-41, 2011.
G. M. Kumar and S. Tiwari, “Performance evaluation of conventional and wavelet based OFDM system”, International Journal of Electronics and Communications, Vol. 67, No. 4, pp. 348-354, 2013.
Sunitha Sirvi and Lokesh Tharani, “Wavelet based OFDM system over flat fading channel using NLMS equalization”, International Conference on Computing, Communication and Automation, Noida, India, Jan. 2017.