FIELD: communication systems. SUBSTANCE: channel coder provided with parallel- or series-connected convolution coders has first coder for coding input data bits, multiplier incorporating memory device and index generator for varying order of data bits according to desired method; second coder for coding multiplier output signal; first and second completion devices for completing data blocks of input and output data bits of first and second coders; residual-bit generator for memorizing residual bits used to complete data block; controller and switch for controlling above-described procedures. EFFECT: varying-speed coding and facilitated decoding. 42 cl, 13 dwg
