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Research on Spectrum Optimization Technology for a Wireless Communication System

1
College of Information and Communication Engineering, Harbin Engineering University, Harbin 150001, China
2
Institute of Physics, Nanotechnology and Telecommunications, St. Petersburg State Polytechnical University, 195251 St. Petersburg, Russia
*
Author to whom correspondence should be addressed.
Symmetry 2020, 12(1), 34; https://doi.org/10.3390/sym12010034
Received: 28 November 2019 / Revised: 18 December 2019 / Accepted: 19 December 2019 / Published: 23 December 2019
In this study, the principle of minimum spectral energy leakage is applied, and the mathematical model is also established by the general function through adding different constraints. To allow the target baseband signal to have a high-quality time-domain representation, it is assumed that the baseband signal is an even function. The time-domain waveform has symmetry about the y-axis, and the objective function is obtained by Fourier series approximation. The frequency-domain characteristics of the baseband signals are obtained by adding the energy limitation condition and the boundary restriction condition. Limit a point at the appropriate position of the main lobe of the normalized energy spectral density function, and at the same time, limit the appropriate point at the first side lobe. The changes of the points modified the whole characteristic of the frequency-domain. To more conveniently compare the characteristics of the signal under different constraints, according to the symmetry of the frequency-domain of the signal, the normalized energy spectrum main lobe energy ratio is defined as a parameter, and thereby the spectral performance of the signal is discriminated by the size of this parameter. Through comparative analysis, the signal with the frequency-domain restriction conditions added has a larger normalized energy spectrum main lobe energy ratio. With increasing roll-off factor n, the energy ratio of the main energy spectrum of the normalized spectrum increases accordingly, i.e., the energy leakage is effectively suppressed. The baseband signal can be considered more suitable as a modern wireless communication system and can be obtained by adding a suitable restriction condition and establishing a model with a general function. View Full-Text
Keywords: baseband signal; optimization method; spectrum limiting method; normalized main lobe energy ratio; spectral efficiency baseband signal; optimization method; spectrum limiting method; normalized main lobe energy ratio; spectral efficiency
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MDPI and ACS Style

Liu, M.; Xue, W.; Jia, P.; Makarov, S.B.; Li, B. Research on Spectrum Optimization Technology for a Wireless Communication System. Symmetry 2020, 12, 34. https://doi.org/10.3390/sym12010034

AMA Style

Liu M, Xue W, Jia P, Makarov SB, Li B. Research on Spectrum Optimization Technology for a Wireless Communication System. Symmetry. 2020; 12(1):34. https://doi.org/10.3390/sym12010034

Chicago/Turabian Style

Liu, Mingxin, Wei Xue, Peisong Jia, Sergey B. Makarov, and Beiming Li. 2020. "Research on Spectrum Optimization Technology for a Wireless Communication System" Symmetry 12, no. 1: 34. https://doi.org/10.3390/sym12010034

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