M.S. Tokar

Pridnestrovian State University of Taras Shevchenko (Tiraspol, Pridnestrovian Republic)

The research object of this work is decoding methods and algorithms, including those used in multi-antenna radio communication systems (Multiple Input Multiple Output – MIMO). In view of the fact that the MIMO technology allows to increase the spectral efficiency of communication systems, it is recommended by the International Telecommunication Union for direct application in the deployment of 5G mobile networks and in the prospects for 6G. These communication networks have high requirements for spectral efficiency, noise immunity and capacity, which, among other things, leads to an increase in the computational resource of the receiver, the value of which directly depends on the decoding algorithms used. The increase in the complexity of the receiver entails an increase in its cost. Thus, the task of developing a decoding algorithm with low computational complexity and applicable for space-time block coding systems, including differential coding, was posed in the work. 

The article proposes a matrix decoding algorithm that meets the above requirements and is based on the use of Voronoi partitioning, according to which a decoding matrix is compiled, the values of the elements of which are the numbers of the symbols of the used modulation constellation. The applicability of the developed algorithm in MIMO systems depends on the signal-to-noise ratio in the channel. The algorithm can also be used in SISO systems, while its computational complexity is several mathematical operations and does not depend on the size of the modulation constellation, bandwidth stability and signal-to-noise ratio. Since this work is a continuation of research devoted to the development and implementation of the transmission method with differential space-time block coding (DSTBC) proposed by the author, then during the simulation the developed decoding algorithm was introduced into the DSTBC decoder. 

The presented results of modeling and comparing the computational complexity of a typical method for transmitting the DSTBC and the developed method of DSTBC using the maximum likelihood algorithm and the matrix decoding algorithm demonstrate a decrease in the computational complexity of the developed method of DSTBC starting from the signal-to-noise ratio in the channel of about  10 dB. Proceeding from this, the implementation of the developed method for the transmission of the DSTBC together with the matrix decoding algorithm is an effective solution aimed at reducing the computing resource of the transmission systems.

Tokar M.S. Low complexity decoding algorithm for differential space-time block coding transmission systems. Radiotekhnika. 2021.  V. 85. № 4. P. 89−98. DOI: https://doi.org/10.18127/j00338486-202104-09 (In Russian)

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