Methods of soft decoding of cascade code constructions based on the
schemes-products of linear block codes (Turbo Product Codes) are considered.
An approach is being developed based on the iterative exchange of soft solutions
between block codes constituting a cascade design. It is shown that a sequential
execution of procedures for the formation of ordered subsets of test
equations and the logarithms estimation of a likelihood ratio allows decoding of
turbo-productive codes according to the criterion of minimizing the erroneous
reception of code symbols.