SPbPU: Noiseproof codings for a 5G

Scientists of Peter the Great St.Petersburg Polytechnic University offered the new system of noiseproof coding for fifth generation of mobile communication (5G).

Noiseproof coding — science about the methods of entering of redundancy into information for the purpose of its error protection arising by transfer or storage. For example, the human speech has redundancy — not each combination of sounds or letters is an admissible word. It gives the chance to people to communicate even in very noisy premises. A task of developers of storage systems and information transfers which are an integral part of gadgets, phones, computers is development of simple and safe methods of a pomekhozashchita of digital data.

Scientists of SPbPU generalized constructions of polar codes and received polar subcodes

At many universities of the world works on improvement of polar codes — the methods of noiseproof coding developed by the Turkish erudite E. Arikan are conducted. The Polytechnic University in the field achieved considerable progress.

"We managed to construct codes which on the adjusting capability and simplicity of decoding exceed competitors — the associate professor of the Higher school of software engineering of SPbPU Pyotr Trifonov shares. — We generalized constructions of the polar codes offered by Arikan and received polar subcodes. For this purpose we excluded a part of code words which can be easily confused among themselves by the receiver from polar codes of Arikan and also introduced additional restrictions for characters of these words that simplifies error correction by the accepting device".

Besides, scientists of SPbPU offered computationally simple decoding algorithm for polar codes and subcodes. Process of decoding can be interpreted as search of the shortest way in a labyrinth. Due to use of data on a median number of the errors which are shown on different phases of decoding (i.e. in labyrinth corridors), it was succeeded to reduce complexity of decoding considerably. As a result scientists of Polytechnic University at the same time received the big adjusting capability, than at the low-density (LDPC) codes which are widely applied now, and much smaller complexity of decoding.

Than more the adjusting capability of the used code, subjects in more difficult conditions is capable to function an information transmission system, it is more than the radius of its action, she is capable to support bigger number of users. And thanks to the fact that scientists of SPbPU reduced complexity of the used decoding algorithms communication devices will be able to consume less energy and longer to work at one battery power.

Polar codes did not find application in real devices yet, but now different generalizations of polar codes are considered by the largest international organizations for implementation in the standard of mobile communication of fifth generation.

The theoretical base describing the principle of creation of polar subcodes and algorithms of their decoding is worked already out. Now scientists work on bringing them to the status suitable for standardization, and after to start development of specific devices.

Results of a research were shown within the conferences 11th International ITG Conference on Systems, Communications and Coding (Hamburg, February, 2017), IEEE Wireless Communications and Networking Conference (San Francisco, March, 2017), IEEE International Symposium on Information Theory (June, 2017).