This is the question about Sigfox radio specification.
Specifically, in Section 3.10 of the specification, we have a convolutional coding (after CRC) with three possible polynominals.
I am wonder whether really error correcting code (ECC) because the output and the input lengths are identical (Figure 3-6 in the specification, or see below).
The question is that if this is ECC, could anyone tell me what is the code rate? And if this is not ECC, what is its role?