Optimization of Iterative Channel State Estimation Algorithms in SCMA System
https://doi.org/10.32603/1993-8985-2018-21-3-23-34
Abstract
Optimization of iterative algorithms for channel state estimation in a sparse coding multiple-access system (SCMA) is performed to reduce computational costs of the receiver. It is shown that when a signal-to-noise ratio (SNR) does not exceed 10 dB, one iteration of the algorithm is sufficient, and an increase in the number of iterations does not lead to an increase in spectral efficiency. Simulation demonstrates a possibility of a reasonable choice of the total number of decoder iterations and their distribution between different stages of the channel estimation. For an uncoded system, iterative re-estimation of the channel is proposed, as well as ways to reduce computational costs during its calculation. In the coded system, at a low SNR the achieved spectral efficiency values are approximately similar to those with pilot-only channel estimation. The article provides recommendations for the placement of data symbols and pilot signals in re-source blocks to increase the system spectral efficiency.
About the Authors
V. P. Klimentyev
Saint Petersburg Electrotechnical University "LETI".
Russian Federation
Russian Federation
Vyacheslav P. Klimentyev – Master’s Degree in radio engineering (2013), postgraduate student of the Department of Theoretical Fundamentals of Radio Engineering of Saint Petersburg Electrotechnical University "LETI". The author of 18 scientific publications. Area of expertise: signal processing; digital communications.
5, Professor Popov Str., 197376, St. Petersburg.
A. B. Sergienko
Saint Petersburg Electrotechnical University "LETI".
Russian Federation
Russian Federation
Alexander B. – PhD in Engineering (1995), Associate Professor (1998), Professor (2018) of the Department of Theoretical Fundamentals of Radio Engineering of Saint Petersburg Electrotechnical University "LETI", IEEE member (1998). The author of 102 scientific publications. Area of expertise: signal processing; digital communications.
5, Professor Popov Str., 197376, St. Petersburg
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Review
For citations:
Klimentyev V.P., Sergienko A.B. Optimization of Iterative Channel State Estimation Algorithms in SCMA System. Journal of the Russian Universities. Radioelectronics. 2018;(3):23-34. (In Russ.) https://doi.org/10.32603/1993-8985-2018-21-3-23-34
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